refactor(snaps): restore point markers

fix: element fully overlapping frame

.codesandbox/Dockerfile

@@ -1,4 +1,4 @@
-FROM node:18-bullseye
+FROM node:24-bullseye
 
 # Vite wants to open the browser using `open`, so we
 # need to install those utils.

Dockerfile

@@ -1,4 +1,4 @@
-FROM --platform=${BUILDPLATFORM} node:18 AS build
+FROM --platform=${BUILDPLATFORM} node:24 AS build
 
 WORKDIR /opt/node_app
 
@@ -13,7 +13,7 @@ ARG NODE_ENV=production
 
 RUN npm_config_target_arch=${TARGETARCH} yarn build:app:docker
 
-FROM --platform=${TARGETPLATFORM} nginx:1.27-alpine
+FROM nginx:1.27-alpine
 
 COPY --from=build /opt/node_app/excalidraw-app/build /usr/share/nginx/html
 

dev-docs/docs/codebase/transactions.mdx

@@ -1,125 +0,0 @@
-# Transactions
-
-Transactions let many live scene updates render immediately while still committing a single durable history entry.
-
-Typical use case:
-
-- AI streaming emits many `NEVER` updates for real-time feedback.
-- Those updates advance the live scene and store snapshot, but do not create undo history.
-- A transaction records the intended logical delta separately, then commits one synthetic durable increment at the end.
-
-## Key Files
-
-### `packages/excalidraw/transaction/`
-
-- `transaction.ts`
-  - `Transaction` is the per-tx instance.
-  - `updateScene()` applies live updates with `captureUpdate: NEVER`.
-  - `updateElements()` is a typed partial-patch helper over `updateScene()`.
-  - `commit()` builds synthetic snapshots and commits one durable entry.
-  - `cancel()` ends the tx without committing history.
-- `ledger.ts`
-  - `TransactionLedger` keeps per-element baseline, target, and touched props across tx steps.
-  - `buildSyntheticSnapshots()` reconciles tx intent with the live scene using `live-wins-per-prop`.
-- `undoOverridePlanner.ts`
-  - Tracks tx intermediate values.
-  - Produces undo override candidates for regular user history entries that were recorded while a tx was active.
-- `manager.ts`
-  - Owns tx lifecycle state and active-tx priority.
-  - Injects tx undo markers into durable deltas at record time.
-  - Resolves effective history deltas at undo/redo time.
-- `diff.ts` / `types.ts`
-  - Shared diff helpers and transaction-specific types.
-
-### `packages/element/src/store.ts`
-
-- `store.commitSyntheticIncrement()`
-  - Builds `StoreSnapshot -> StoreChange -> StoreDelta` from logical before/after snapshots.
-  - Commits the synthetic durable increment immediately through an isolated path.
-  - Does not flush unrelated pending micro actions.
-- `StoreDelta.markers`
-  - Carries extra history markers such as `txUndoOverrides`.
-
-### `packages/excalidraw/history.ts`
-
-- `onBeforeRecord()`
-  - Lets the transaction manager attach markers before a durable delta becomes a history entry.
-- `setEffectiveDeltaResolver()`
-  - Lets the transaction manager rewrite a history delta at undo/redo time before it is applied.
-
-## Flow
-
-1. Caller creates a transaction.
-2. `tx.updateScene()` applies live updates with `NEVER`.
-3. The ledger records net element changes; appState intent is accumulated separately.
-4. Regular user durable edits that happen while the tx is active may receive tx undo markers.
-5. `tx.commit()` asks the ledger for logical before/after snapshots and calls `store.commitSyntheticIncrement()`.
-6. Undo/redo later uses the manager's effective-delta resolver to decide whether ended tx markers should patch the baseline of a regular history entry.
-
-Result:
-
-- live rendering stays immediate;
-- one tx still produces one durable history entry;
-- interleaved regular edits can undo back to the correct pre-tx baseline.
-
-## Undo Examples
-
-### Interleaved Regular Edit
-
-1. Baseline: `rect = (x: 0, stroke: black)`
-2. Tx updates it live to `(x: 200, stroke: red)` with `NEVER`
-3. User makes a regular durable edit: `(x: 200, stroke: purple)`
-4. Tx commits; live stays purple
-
-The user history entry was recorded while the tx was active, so its local baseline is `red`.
-If undo later runs after the tx has ended, restoring `red` is wrong: the correct pre-tx baseline is `black`.
-
-To fix this:
-
-- record-time attaches a tx undo marker to the user history entry
-- perform-time checks whether the tx has already ended
-- if ended, the effective delta is patched so undo restores `black` instead of `red`
-
-### Active Tx vs Ended Tx
-
-Using the same example:
-
-- if the user undoes while the tx is still active, the marker stays inactive and undo restores the tx intermediate value (`red`)
-- if the user undoes after the tx has ended, the marker becomes active and undo restores the pre-tx baseline (`black`)
-
-So markers are recorded early, but applied conditionally.
-
-## AppState
-
-Elements use ledger snapshots. AppState does not.
-
-The transaction instead keeps:
-
-- `initialAppState`: observed appState at tx start
-- `accumulatedAppState`: merged caller intent from `tx.updateScene({ appState })`
-
-At commit, the transaction computes the final appState patch and passes it into `store.commitSyntheticIncrement()`.
-
-## Example
-
-```ts
-const tx = app.transactionManager.create();
-
-tx.updateScene({ elements: updatedElementsA });
-tx.updateScene({ elements: updatedElementsB });
-tx.updateElements({
-  elements: [
-    { id: "rect-1", type: "rectangle", updates: { strokeColor: "#f00" } },
-    { id: "rect-2", type: "rectangle", updates: { x: 120 } },
-  ],
-});
-
-tx.commit();
-```
-
-## Notes
-
-- `commit()` and `cancel()` are idempotent.
-- `updateScene()` and `updateElements()` throw after the tx has ended.
-- Conflict handling inside synthetic snapshots is fixed to `live-wins-per-prop`.
-- Multi-tx interleaving is supported through manager-owned lifecycle tracking and active-tx priority.

packages/element/src/binding.ts

@@ -1943,9 +1943,9 @@ export const calculateFixedPointForElbowArrowBinding = (
   return {
     fixedPoint: normalizeFixedPoint([
       (nonRotatedSnappedGlobalPoint[0] - hoveredElement.x) /
-        hoveredElement.width,
+        Math.max(hoveredElement.width, PRECISION),
       (nonRotatedSnappedGlobalPoint[1] - hoveredElement.y) /
-        hoveredElement.height,
+        Math.max(hoveredElement.height, PRECISION),
     ]),
   };
 };
@@ -1976,9 +1976,11 @@ export const calculateFixedPointForNonElbowArrowBinding = (
 
   // Calculate the ratio relative to the element's bounds
   const fixedPointX =
-    (nonRotatedPoint[0] - hoveredElement.x) / hoveredElement.width;
+    (nonRotatedPoint[0] - hoveredElement.x) /
+    Math.max(hoveredElement.width, PRECISION);
   const fixedPointY =
-    (nonRotatedPoint[1] - hoveredElement.y) / hoveredElement.height;
+    (nonRotatedPoint[1] - hoveredElement.y) /
+    Math.max(hoveredElement.height, PRECISION);
 
   return {
     fixedPoint: normalizeFixedPoint([fixedPointX, fixedPointY]),

packages/element/src/duplicate.ts

@@ -250,6 +250,9 @@ export const duplicateElements = (
     elementsWithDuplicates.splice(index + 1, 0, ...castArray(elements));
   };
 
+  // main
+  // ---------------------------------------------------------------------------
+
   const frameIdsToDuplicate = new Set(
     elements
       .filter(

packages/element/src/elbowArrow.ts

@@ -2124,8 +2124,8 @@ const normalizeArrowElementUpdate = (
     offsetY < -MAX_POS ||
     offsetY > MAX_POS ||
     offsetX + points[points.length - 1][0] < -MAX_POS ||
-    offsetY + points[points.length - 1][0] > MAX_POS ||
+    offsetX + points[points.length - 1][0] > MAX_POS ||
-    offsetX + points[points.length - 1][1] < -MAX_POS ||
+    offsetY + points[points.length - 1][1] < -MAX_POS ||
     offsetY + points[points.length - 1][1] > MAX_POS
   ) {
     console.error(

packages/element/src/frame.ts

@@ -19,6 +19,7 @@ import {
   getElementAbsoluteCoords,
   doBoundsIntersect,
   getElementBounds,
+  boundsContainBounds,
 } from "./bounds";
 import { mutateElement } from "./mutateElement";
 import { getBoundTextElement, getContainerElement } from "./textElement";
@@ -101,8 +102,9 @@ export const isElementContainingFrame = (
   frame: ExcalidrawFrameLikeElement,
   elementsMap: ElementsMap,
 ) => {
-  return getElementsWithinSelection([frame], element, elementsMap).some(
+  return boundsContainBounds(
-    (e) => e.id === frame.id,
+    getElementBounds(element, elementsMap),
+    getElementBounds(frame, elementsMap),
   );
 };
 

packages/element/src/selection.ts

@@ -34,7 +34,6 @@ import {
   elementOverlapsWithFrame,
   getContainingFrame,
   getFrameChildren,
-  isElementIntersectingFrame,
 } from "./frame";
 
 import { LinearElementEditor } from "./linearElementEditor";
@@ -170,7 +169,7 @@ export const getElementsWithinSelection = (
     const associatedFrame = getContainingFrame(element, elementsMap);
     if (
       associatedFrame &&
-      isElementIntersectingFrame(element, associatedFrame, elementsMap)
+      elementOverlapsWithFrame(element, associatedFrame, elementsMap)
     ) {
       const frameAABB = getElementBounds(associatedFrame, elementsMap);
       elementAABB = [
@@ -209,10 +208,9 @@ export const getElementsWithinSelection = (
     if (boundsContainBounds(selectionBounds, commonAABB)) {
       if (framesInSelection && isFrameLikeElement(element)) {
         framesInSelection.add(element.id);
-      } else {
-        elementsInSelection.push(element);
-        continue;
       }
+      elementsInSelection.push(element);
+      continue;
     }
 
     // 2. Handle the case where the label is overlapped by the selection box

packages/element/src/sortElements.ts

@@ -1,59 +1,56 @@
-import { arrayToMapWithIndex } from "@excalidraw/common";
+import { arrayToMap } from "@excalidraw/common";
 
 import type { ExcalidrawElement } from "./types";
 
-const normalizeGroupElementOrder = (elements: readonly ExcalidrawElement[]) => {
+const defragmentGroups = (elements: readonly ExcalidrawElement[]) => {
-  const origElements: ExcalidrawElement[] = elements.slice();
+  const groupIdAtLevel = (element: ExcalidrawElement, level: number) => {
-  const sortedElements = new Set<ExcalidrawElement>();
+    return element.groupIds[element.groupIds.length - level - 1];
-
-  const orderInnerGroups = (
-    elements: readonly ExcalidrawElement[],
-  ): ExcalidrawElement[] => {
-    const firstGroupSig = elements[0]?.groupIds?.join("");
-    const aGroup: ExcalidrawElement[] = [elements[0]];
-    const bGroup: ExcalidrawElement[] = [];
-    for (const element of elements.slice(1)) {
-      if (element.groupIds?.join("") === firstGroupSig) {
-        aGroup.push(element);
-      } else {
-        bGroup.push(element);
-      }
-    }
-    return bGroup.length ? [...aGroup, ...orderInnerGroups(bGroup)] : aGroup;
   };
 
-  const groupHandledElements = new Map<string, true>();
+  const orderLevel = (
+    levelElements: readonly ExcalidrawElement[],
+    level: number,
+  ): ExcalidrawElement[] => {
+    const buckets = new Map<string, ExcalidrawElement[]>();
+    // Slots preserve first-occurrence order: a groupId reserves its slot
+    // the first time one of its members is seen; loose elements occupy
+    // their own slot. Groups are then expanded (and recursed into) in place.
+    const slots: (ExcalidrawElement | string)[] = [];
 
-  origElements.forEach((element, idx) => {
+    for (const element of levelElements) {
-    if (groupHandledElements.has(element.id)) {
+      const groupId = groupIdAtLevel(element, level);
-      return;
+      if (groupId === undefined) {
-    }
+        slots.push(element);
-    if (element.groupIds?.length) {
+        continue;
-      const topGroup = element.groupIds[element.groupIds.length - 1];
-      const groupElements = origElements.slice(idx).filter((element) => {
-        const ret = element?.groupIds?.some((id) => id === topGroup);
-        if (ret) {
-          groupHandledElements.set(element!.id, true);
-        }
-        return ret;
-      });
-
-      for (const elem of orderInnerGroups(groupElements)) {
-        sortedElements.add(elem);
       }
-    } else {
+      let bucket = buckets.get(groupId);
-      sortedElements.add(element);
+      if (!bucket) {
+        bucket = [];
+        buckets.set(groupId, bucket);
+        slots.push(groupId);
+      }
+      bucket.push(element);
     }
-  });
+
+    return slots.flatMap((slot) =>
+      typeof slot === "string"
+        ? orderLevel(buckets.get(slot)!, level + 1)
+        : [slot],
+    );
+  };
+
+  // `groupIds` is stored innermost-first, so the outermost group is the
+  // last entry. We recurse from level 0 (outermost) inward.
+  const sortedElements = orderLevel(elements, 0);
 
   // if there's a bug which resulted in losing some of the elements, return
   // original instead as that's better than losing data
-  if (sortedElements.size !== elements.length) {
+  if (sortedElements.length !== elements.length) {
-    console.error("normalizeGroupElementOrder: lost some elements... bailing!");
+    console.error("defragmentGroups: lost some elements... bailing!");
     return elements;
   }
 
-  return [...sortedElements];
+  return sortedElements;
 };
 
 /**
@@ -68,39 +65,40 @@ const normalizeGroupElementOrder = (elements: readonly ExcalidrawElement[]) => {
 const normalizeBoundElementsOrder = (
   elements: readonly ExcalidrawElement[],
 ) => {
-  const elementsMap = arrayToMapWithIndex(elements);
+  const elementsMap = arrayToMap(elements);
 
-  const origElements: (ExcalidrawElement | null)[] = elements.slice();
   const sortedElements = new Set<ExcalidrawElement>();
 
-  origElements.forEach((element, idx) => {
+  for (const element of elements) {
-    if (!element) {
+    if (sortedElements.has(element)) {
-      return;
+      continue;
     }
+
     if (element.boundElements?.length) {
       sortedElements.add(element);
-      origElements[idx] = null;
+      for (const boundElement of element.boundElements) {
-      element.boundElements.forEach((boundElement) => {
         const child = elementsMap.get(boundElement.id);
         if (child && boundElement.type === "text") {
-          sortedElements.add(child[0]);
+          sortedElements.add(child);
-          origElements[child[1]] = null;
         }
-      });
-    } else if (element.type === "text" && element.containerId) {
-      const parent = elementsMap.get(element.containerId);
-      if (!parent?.[0].boundElements?.find((x) => x.id === element.id)) {
-        sortedElements.add(element);
-        origElements[idx] = null;
-
-        // if element has a container and container lists it, skip this element
-        // as it'll be taken care of by the container
       }
-    } else {
+      continue;
-      sortedElements.add(element);
-      origElements[idx] = null;
     }
-  });
+
+    // if element has a container and container lists it, skip this element
+    // as it'll be taken care of by the container
+    if (
+      element.type === "text" &&
+      element.containerId &&
+      elementsMap
+        .get(element.containerId)
+        ?.boundElements?.some((el) => el.id === element.id)
+    ) {
+      continue;
+    }
+
+    sortedElements.add(element);
+  }
 
   // if there's a bug which resulted in losing some of the elements, return
   // original instead as that's better than losing data
@@ -117,5 +115,5 @@ const normalizeBoundElementsOrder = (
 export const normalizeElementOrder = (
   elements: readonly ExcalidrawElement[],
 ) => {
-  return normalizeBoundElementsOrder(normalizeGroupElementOrder(elements));
+  return normalizeBoundElementsOrder(defragmentGroups(elements));
 };

packages/element/src/store.ts

@@ -111,67 +111,6 @@ export class Store {
     this.scheduleAction(CaptureUpdateAction.IMMEDIATELY);
   }
 
-  /**
-   * Commits a synthetic durable history entry without changing the live scene.
-   *
-   * Builds StoreSnapshot → StoreChange → StoreDelta from the provided
-   * logical before/after element maps and optional appState patches, then
-   * emits the resulting durable increment immediately through an isolated
-   * path that does not flush pending micro actions.
-   *
-   * appState patches are merged on top of the current observed appState
-   * baseline so only the provided keys participate in the synthetic diff.
-   */
-  public commitSyntheticIncrement(params: {
-    logicalBefore: {
-      elements: SceneElementsMap;
-      appState?: Partial<ObservedAppState>;
-    };
-    logicalAfter: {
-      elements: SceneElementsMap;
-      appState?: Partial<ObservedAppState>;
-    };
-  }): boolean {
-    const { logicalBefore, logicalAfter } = params;
-    const observedAppStateBaseline = this.snapshot.appState;
-    const syntheticAppStateBefore = logicalBefore.appState
-      ? { ...observedAppStateBaseline, ...logicalBefore.appState }
-      : observedAppStateBaseline;
-    const syntheticAppStateAfter = logicalAfter.appState
-      ? { ...observedAppStateBaseline, ...logicalAfter.appState }
-      : observedAppStateBaseline;
-    const didAppStateChange = Delta.isRightDifferent(
-      syntheticAppStateBefore,
-      syntheticAppStateAfter,
-    );
-    const prevSnapshot = StoreSnapshot.create(
-      logicalBefore.elements,
-      syntheticAppStateBefore,
-      {
-        didElementsChange: true,
-        didAppStateChange,
-      },
-    );
-    const nextSnapshot = StoreSnapshot.create(
-      logicalAfter.elements,
-      syntheticAppStateAfter,
-      {
-        didElementsChange: true,
-        didAppStateChange,
-      },
-    );
-    const change = StoreChange.create(prevSnapshot, nextSnapshot);
-    const delta = StoreDelta.calculate(prevSnapshot, nextSnapshot);
-
-    if (delta.isEmpty()) {
-      return false;
-    }
-
-    this.emitIsolatedDurableIncrement(change, delta);
-
-    return true;
-  }
-
   /**
    * Schedule special "micro" actions, to-be executed before the next commit, before it executes a scheduled "macro" action.
    */
@@ -267,7 +206,6 @@ export class Store {
   public clear(): void {
     this.snapshot = StoreSnapshot.empty();
     this.scheduledMacroActions = new Set();
-    this.scheduledMicroActions = [];
   }
 
   /**
@@ -307,24 +245,6 @@ export class Store {
     }
   }
 
-  /**
-   * Emits a synthetic durable increment immediately without draining the
-   * regular micro-action queue.
-   */
-  private emitIsolatedDurableIncrement(change: StoreChange, delta: StoreDelta) {
-    const nextSnapshot = this.applyChangeToSnapshot(change);
-
-    if (!nextSnapshot) {
-      return;
-    }
-
-    try {
-      this.emitDurableIncrement(nextSnapshot, change, delta);
-    } finally {
-      this.snapshot = nextSnapshot;
-    }
-  }
-
   /**
    * Performs change calculation and emits an ephemeral increment.
    *
@@ -571,89 +491,6 @@ export class EphemeralIncrement extends StoreIncrement {
   }
 }
 
-/**
- * Serializable delta marker used to recover pre-tx undo baselines
- * without rewriting history stack entries.
- */
-export type TxUndoOverride = {
-  txId: string;
-  elementId: string;
-  prop: string;
-  expectedInsertedValue: unknown;
-  preTxBaselineValue: unknown;
-  consumedKey: string;
-};
-
-export type StoreDeltaMarkers = {
-  txUndoOverrides?: TxUndoOverride[];
-};
-
-const cloneTxUndoOverride = (override: TxUndoOverride): TxUndoOverride => ({
-  ...override,
-});
-
-const cloneStoreDeltaMarkers = (
-  markers: StoreDeltaMarkers | undefined,
-): StoreDeltaMarkers | undefined =>
-  markers
-    ? {
-        ...markers,
-        txUndoOverrides: markers.txUndoOverrides?.map(cloneTxUndoOverride),
-      }
-    : undefined;
-
-const pruneStoreDeltaMarkers = (delta: StoreDelta) => {
-  const txUndoOverrides = delta.markers?.txUndoOverrides;
-  if (!txUndoOverrides || txUndoOverrides.length === 0) {
-    return;
-  }
-
-  const updatedEntries = delta.elements.updated as Record<
-    string,
-    Delta<Record<string, unknown>>
-  >;
-  const nextTxUndoOverrides = txUndoOverrides.filter((override) => {
-    const updatedEntry = updatedEntries[override.elementId];
-    return (
-      !!updatedEntry &&
-      Object.prototype.hasOwnProperty.call(updatedEntry.inserted, override.prop)
-    );
-  });
-
-  if (nextTxUndoOverrides.length === txUndoOverrides.length) {
-    return;
-  }
-
-  if (nextTxUndoOverrides.length === 0) {
-    delta.markers = undefined;
-    return;
-  }
-
-  delta.markers = {
-    ...delta.markers,
-    txUndoOverrides: nextTxUndoOverrides.map(cloneTxUndoOverride),
-  };
-};
-
-export const mergeStoreDeltaMarkers = (
-  delta: StoreDelta,
-  markers: StoreDeltaMarkers,
-) => {
-  const txUndoOverrides = markers.txUndoOverrides ?? [];
-  if (txUndoOverrides.length === 0) {
-    return;
-  }
-
-  const existing = delta.markers?.txUndoOverrides ?? [];
-  delta.markers = {
-    ...delta.markers,
-    txUndoOverrides: [
-      ...existing.map(cloneTxUndoOverride),
-      ...txUndoOverrides.map(cloneTxUndoOverride),
-    ],
-  };
-};
-
 /**
  * Represents a captured delta by the Store.
  */
@@ -662,7 +499,6 @@ export class StoreDelta {
     public readonly id: string,
     public readonly elements: ElementsDelta,
     public readonly appState: AppStateDelta,
-    public markers?: StoreDeltaMarkers,
   ) {}
 
   /**
@@ -672,16 +508,12 @@ export class StoreDelta {
     elements: ElementsDelta,
     appState: AppStateDelta,
     opts: {
-      id?: string;
+      id: string;
-      markers?: StoreDeltaMarkers;
+    } = {
-    } = {},
+      id: randomId(),
+    },
   ) {
-    return new this(
+    return new this(opts.id, elements, appState);
-      opts.id ?? randomId(),
-      elements,
-      appState,
-      cloneStoreDeltaMarkers(opts.markers),
-    );
   }
 
   /**
@@ -706,12 +538,11 @@ export class StoreDelta {
    * Restore a store delta instance from a DTO.
    */
   public static restore(storeDeltaDTO: DTO<StoreDelta>) {
-    const { id, elements, appState, markers } = storeDeltaDTO;
+    const { id, elements, appState } = storeDeltaDTO;
     return new this(
       id,
       ElementsDelta.restore(elements),
       AppStateDelta.restore(appState),
-      cloneStoreDeltaMarkers(markers),
     );
   }
 
@@ -722,12 +553,11 @@ export class StoreDelta {
     id,
     elements: { added, removed, updated },
     appState: { delta: appStateDelta },
-    markers,
   }: DTO<StoreDelta>) {
     const elements = ElementsDelta.create(added, removed, updated);
     const appState = AppStateDelta.create(appStateDelta);
 
-    return new this(id, elements, appState, cloneStoreDeltaMarkers(markers));
+    return new this(id, elements, appState);
   }
 
   /**
@@ -739,10 +569,8 @@ export class StoreDelta {
     for (const delta of deltas) {
       aggregatedDelta.elements.squash(delta.elements);
       aggregatedDelta.appState.squash(delta.appState);
-      mergeStoreDeltaMarkers(aggregatedDelta, delta.markers ?? {});
     }
 
-    pruneStoreDeltaMarkers(aggregatedDelta);
     return aggregatedDelta;
   }
 
@@ -750,12 +578,7 @@ export class StoreDelta {
    * Inverse store delta, creates new instance of `StoreDelta`.
    */
   public static inverse(delta: StoreDelta) {
-    const inversed = this.create(
+    return this.create(delta.elements.inverse(), delta.appState.inverse());
-      delta.elements.inverse(),
-      delta.appState.inverse(),
-      { markers: delta.markers },
-    );
-    return inversed;
   }
 
   /**
@@ -791,7 +614,7 @@ export class StoreDelta {
     nextElements: SceneElementsMap,
     modifierOptions?: "deleted" | "inserted",
   ): StoreDelta {
-    const nextDelta = this.create(
+    return this.create(
       delta.elements.applyLatestChanges(
         prevElements,
         nextElements,
@@ -800,11 +623,8 @@ export class StoreDelta {
       delta.appState,
       {
         id: delta.id,
-        markers: delta.markers,
       },
     );
-    pruneStoreDeltaMarkers(nextDelta);
-    return nextDelta;
   }
 
   public static empty() {

packages/element/tests/frame.test.tsx

@@ -2,6 +2,7 @@ import {
   convertToExcalidrawElements,
   Excalidraw,
 } from "@excalidraw/excalidraw";
+import { arrayToMap } from "@excalidraw/common";
 
 import { API } from "@excalidraw/excalidraw/tests/helpers/api";
 import { Keyboard, Pointer } from "@excalidraw/excalidraw/tests/helpers/ui";
@@ -10,7 +11,12 @@ import {
   render,
 } from "@excalidraw/excalidraw/tests/test-utils";
 
-import type { ExcalidrawElement } from "../src/types";
+import { elementOverlapsWithFrame } from "../src/frame";
+
+import type {
+  ExcalidrawElement,
+  ExcalidrawFrameLikeElement,
+} from "../src/types";
 
 const { h } = window;
 const mouse = new Pointer("mouse");
@@ -125,6 +131,26 @@ describe("adding elements to frames", () => {
     });
   });
 
+  it("should treat an element fully containing a frame as overlapping the frame", () => {
+    const containingRect = API.createElement({
+      type: "rectangle",
+      x: -50,
+      y: -50,
+      width: 250,
+      height: 250,
+    });
+
+    API.setElements([containingRect, frame]);
+
+    expect(
+      elementOverlapsWithFrame(
+        containingRect,
+        frame as ExcalidrawFrameLikeElement,
+        arrayToMap(h.elements),
+      ),
+    ).toBe(true);
+  });
+
   const commonTestCases = async (
     func: typeof resizeFrameOverElement | typeof dragElementIntoFrame,
   ) => {
@@ -415,6 +441,22 @@ describe("adding elements to frames", () => {
   describe("dragging elements into the frame", async () => {
     await commonTestCases(dragElementIntoFrame);
 
+    it("should add a dragged element fully containing the frame", () => {
+      const containingRect = API.createElement({
+        type: "rectangle",
+        x: 220,
+        y: 20,
+        width: 300,
+        height: 300,
+      });
+
+      API.setElements([frame, containingRect]);
+
+      dragElementIntoFrame(frame, containingRect);
+
+      expect(API.getElement(containingRect).frameId).toBe(frame.id);
+    });
+
     it.skip("should drag element inside, duplicate it and keep it in frame", () => {
       API.setElements([frame, rect2]);
 

packages/element/tests/sortElements.test.ts

@@ -326,19 +326,59 @@ describe("normalizeElementsOrder", () => {
       ]),
       [
         "BA_rect1",
+        "CBA_rect3",
+        "CBA_rect7",
         "BA_rect5",
         "BA_rect6",
         "A_rect2",
         "A_rect5",
-        "CBA_rect3",
-        "CBA_rect7",
         "rect4",
         "X_rect8",
-        "X_rect11",
         "YX_rect10",
+        "X_rect11",
         "rect9",
       ],
     );
+    assertOrder(
+      normalizeElementOrder([
+        API.createElement({
+          id: "A_rect1",
+          type: "rectangle",
+          groupIds: ["A"],
+        }),
+        API.createElement({
+          id: "CBA_rect2",
+          type: "rectangle",
+          groupIds: ["C", "B", "A"],
+        }),
+        API.createElement({
+          id: "A_rect3",
+          type: "rectangle",
+          groupIds: ["A"],
+        }),
+      ]),
+      ["A_rect1", "CBA_rect2", "A_rect3"],
+    );
+    assertOrder(
+      normalizeElementOrder([
+        API.createElement({
+          id: "abcT_rect1",
+          type: "rectangle",
+          groupIds: ["ab", "c", "T"],
+        }),
+        API.createElement({
+          id: "abcT_rect2",
+          type: "rectangle",
+          groupIds: ["a", "bc", "T"],
+        }),
+        API.createElement({
+          id: "abcT_rect3",
+          type: "rectangle",
+          groupIds: ["ab", "c", "T"],
+        }),
+      ]),
+      ["abcT_rect1", "abcT_rect3", "abcT_rect2"],
+    );
   });
 
   // TODO

packages/element/tests/store.test.ts

@@ -1,140 +0,0 @@
-import { API } from "@excalidraw/excalidraw/tests/helpers/api";
-
-import { arrayToMap } from "@excalidraw/common";
-
-import type App from "@excalidraw/excalidraw/components/App";
-
-import type { ObservedAppState } from "@excalidraw/excalidraw/types";
-import type {
-  ExcalidrawElement,
-  SceneElementsMap,
-} from "@excalidraw/element/types";
-
-import {
-  CaptureUpdateAction,
-  Store,
-  StoreSnapshot,
-  newElementWith,
-} from "../src";
-
-const getScheduledMicroActionCount = (store: Store) =>
-  (
-    store as unknown as {
-      scheduledMicroActions: Array<() => void>;
-    }
-  ).scheduledMicroActions.length;
-
-const flushMicroActions = (store: Store) => {
-  (
-    store as unknown as {
-      flushMicroActions: () => void;
-    }
-  ).flushMicroActions();
-};
-
-const toSceneElementsMap = (
-  elements: readonly ExcalidrawElement[],
-): SceneElementsMap => arrayToMap(elements) as SceneElementsMap;
-
-const createStoreHarness = (elements: SceneElementsMap) => {
-  const appState: ObservedAppState = StoreSnapshot.empty().appState;
-  const app = {
-    scene: {
-      getElementsMapIncludingDeleted: () => elements,
-    },
-    state: appState,
-  } as unknown as App;
-
-  const store = new Store(app);
-  store.snapshot = StoreSnapshot.create(elements, appState);
-
-  return { store, appState };
-};
-
-describe("Store synthetic increment isolation", () => {
-  it("keeps pending immediate micro actions queued across synthetic commit", () => {
-    const element = API.createElement({
-      type: "rectangle",
-      id: "store-isolated-immediate",
-      x: 0,
-      y: 0,
-    });
-    const baselineElements = toSceneElementsMap([element]);
-    const { store } = createStoreHarness(baselineElements);
-
-    const incrementTypes: Array<"durable" | "ephemeral"> = [];
-    const detach = store.onStoreIncrementEmitter.on((increment) => {
-      incrementTypes.push(increment.type);
-    });
-
-    store.scheduleMicroAction({
-      action: CaptureUpdateAction.IMMEDIATELY,
-      elements: [newElementWith(element, { y: 240 })],
-      appState: undefined,
-    });
-
-    expect(getScheduledMicroActionCount(store)).toBe(1);
-
-    const committed = store.commitSyntheticIncrement({
-      logicalBefore: {
-        elements: baselineElements,
-      },
-      logicalAfter: {
-        elements: toSceneElementsMap([newElementWith(element, { x: 120 })]),
-      },
-    });
-
-    expect(committed).toBe(true);
-    expect(incrementTypes).toEqual(["durable"]);
-    expect(getScheduledMicroActionCount(store)).toBe(1);
-
-    flushMicroActions(store);
-
-    expect(incrementTypes).toEqual(["durable", "durable"]);
-    expect(getScheduledMicroActionCount(store)).toBe(0);
-    detach();
-  });
-
-  it("keeps pending eventually micro actions queued across synthetic commit", () => {
-    const element = API.createElement({
-      type: "rectangle",
-      id: "store-isolated-eventually",
-      x: 0,
-      y: 0,
-    });
-    const baselineElements = toSceneElementsMap([element]);
-    const { store } = createStoreHarness(baselineElements);
-
-    const incrementTypes: Array<"durable" | "ephemeral"> = [];
-    const detach = store.onStoreIncrementEmitter.on((increment) => {
-      incrementTypes.push(increment.type);
-    });
-
-    store.scheduleMicroAction({
-      action: CaptureUpdateAction.EVENTUALLY,
-      elements: [newElementWith(element, { y: 240 })],
-      appState: undefined,
-    });
-
-    expect(getScheduledMicroActionCount(store)).toBe(1);
-
-    const committed = store.commitSyntheticIncrement({
-      logicalBefore: {
-        elements: baselineElements,
-      },
-      logicalAfter: {
-        elements: toSceneElementsMap([newElementWith(element, { x: 120 })]),
-      },
-    });
-
-    expect(committed).toBe(true);
-    expect(incrementTypes).toEqual(["durable"]);
-    expect(getScheduledMicroActionCount(store)).toBe(1);
-
-    flushMicroActions(store);
-
-    expect(incrementTypes).toEqual(["durable", "ephemeral"]);
-    expect(getScheduledMicroActionCount(store)).toBe(0);
-    detach();
-  });
-});

packages/excalidraw/actions/actionFinalize.tsx

@@ -329,7 +329,6 @@ export const actionFinalize = register<FormData>({
         selectionElement: null,
         multiElement: null,
         editingTextElement: null,
-        startBoundElement: null,
         suggestedBinding: null,
         selectedElementIds:
           element &&

packages/excalidraw/appState.ts

@@ -99,7 +99,6 @@ export const getDefaultAppState = (): Omit<
       open: false,
       panels: STATS_PANELS.generalStats | STATS_PANELS.elementProperties,
     },
-    startBoundElement: null,
     suggestedBinding: null,
     frameRendering: { enabled: true, clip: true, name: true, outline: true },
     frameToHighlight: null,
@@ -231,7 +230,6 @@ const APP_STATE_STORAGE_CONF = (<
   selectionElement: { browser: false, export: false, server: false },
   shouldCacheIgnoreZoom: { browser: true, export: false, server: false },
   stats: { browser: true, export: false, server: false },
-  startBoundElement: { browser: false, export: false, server: false },
   suggestedBinding: { browser: false, export: false, server: false },
   frameRendering: { browser: false, export: false, server: false },
   frameToHighlight: { browser: false, export: false, server: false },

packages/excalidraw/components/App.tsx

@@ -361,7 +361,6 @@ import { restoreAppState, restoreElements } from "../data/restore";
 import { getCenter, getDistance } from "../gesture";
 import { History } from "../history";
 import { defaultLang, getLanguage, languages, setLanguage, t } from "../i18n";
-import { TransactionManager } from "../transaction";
 
 import {
   calculateScrollCenter,
@@ -604,6 +603,8 @@ const YOUTUBE_VIDEO_STATES = new Map<
   ValueOf<typeof YOUTUBE_STATES>
 >();
 
+const MAX_EMBEDDABLE_VIEWPORT_SCALE = 4;
+
 let IS_PLAIN_PASTE = false;
 let IS_PLAIN_PASTE_TIMER = 0;
 let PLAIN_PASTE_TOAST_SHOWN = false;
@@ -638,8 +639,7 @@ class App extends React.Component<AppProps, AppState> {
   public library: AppClassProperties["library"];
   public libraryItemsFromStorage: LibraryItems | undefined;
   public id: string;
-  public transactionManager: TransactionManager;
+  private store: Store;
-  public store: Store;
   private history: History;
   public excalidrawContainerValue: {
     container: HTMLDivElement | null;
@@ -834,8 +834,6 @@ class App extends React.Component<AppProps, AppState> {
 
     this.store = new Store(this);
     this.history = new History(this.store);
-    this.transactionManager = new TransactionManager(this);
-    this.transactionManager.attachHistory(this.history);
 
     this.excalidrawContainerValue = {
       container: this.excalidrawContainerRef.current,
@@ -843,6 +841,7 @@ class App extends React.Component<AppProps, AppState> {
     };
 
     this.fonts = new Fonts(this.scene);
+    this.history = new History(this.store);
 
     this.actionManager.registerAll(actions);
     this.actionManager.registerAction(createUndoAction(this.history));
@@ -1738,6 +1737,18 @@ class App extends React.Component<AppProps, AppState> {
             this.state.activeEmbeddable?.element === el &&
             this.state.activeEmbeddable?.state === "hover";
 
+          // scale video embeds based on zoom (capped) so that smaller embeds
+          // on canvas when zoomed are still of legible quality
+          // (note: for some embed types like gdrive, the quality is poor when
+          // scaling mid playback and works only when you initially start the
+          // playback at the higher zoom level)
+          const shouldScaleEmbeddableViewport = src?.type === "video";
+          const embeddableViewportScale = clamp(
+            shouldScaleEmbeddableViewport ? scale : 1,
+            0.75,
+            MAX_EMBEDDABLE_VIEWPORT_SCALE,
+          );
+
           return (
             <div
               key={el.id}
@@ -1804,31 +1815,42 @@ class App extends React.Component<AppProps, AppState> {
                     padding: `${el.strokeWidth}px`,
                   }}
                 >
-                  {(isEmbeddableElement(el)
+                  <div
-                    ? this.props.renderEmbeddable?.(el, this.state)
+                    className="excalidraw__embeddable__content"
-                    : null) ?? (
+                    style={{
-                    <iframe
+                      width: `${embeddableViewportScale * 100}%`,
-                      ref={(ref) => this.cacheEmbeddableRef(el, ref)}
+                      height: `${embeddableViewportScale * 100}%`,
-                      className="excalidraw__embeddable"
+                      transform: `scale(${1 / embeddableViewportScale})`,
-                      srcDoc={
+                    }}
-                        src?.type === "document"
+                  >
-                          ? src.srcdoc(this.state.theme)
+                    {(isEmbeddableElement(el)
-                          : undefined
+                      ? this.props.renderEmbeddable?.(el, this.state)
-                      }
+                      : null) ?? (
-                      src={
+                      <iframe
-                        src?.type !== "document" ? src?.link ?? "" : undefined
+                        ref={(ref) => this.cacheEmbeddableRef(el, ref)}
-                      }
+                        className="excalidraw__embeddable"
-                      // https://stackoverflow.com/q/18470015
+                        srcDoc={
-                      scrolling="no"
+                          src?.type === "document"
-                      referrerPolicy="no-referrer-when-downgrade"
+                            ? src.srcdoc(this.state.theme)
-                      title="Excalidraw Embedded Content"
+                            : undefined
-                      allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture"
+                        }
-                      allowFullScreen={true}
+                        src={
-                      sandbox={`${
+                          src?.type !== "document" ? src?.link ?? "" : undefined
-                        src?.sandbox?.allowSameOrigin ? "allow-same-origin" : ""
+                        }
-                      } allow-scripts allow-forms allow-popups allow-popups-to-escape-sandbox allow-presentation allow-downloads`}
+                        // https://stackoverflow.com/q/18470015
-                    />
+                        scrolling="no"
-                  )}
+                        referrerPolicy="no-referrer-when-downgrade"
+                        title="Excalidraw Embedded Content"
+                        allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture"
+                        allowFullScreen={true}
+                        sandbox={`${
+                          src?.sandbox?.allowSameOrigin
+                            ? "allow-same-origin"
+                            : ""
+                        } allow-scripts allow-forms allow-popups allow-popups-to-escape-sandbox allow-presentation allow-downloads`}
+                      />
+                    )}
+                  </div>
                 </div>
               </div>
             </div>
@@ -4605,11 +4627,6 @@ class App extends React.Component<AppProps, AppState> {
     );
   };
 
-  /** Creates a new transaction for batching mutations into a single undo entry. */
-  public createTransaction: TransactionManager["create"] = () => {
-    return this.transactionManager.create();
-  };
-
   public mutateElement = <TElement extends Mutable<ExcalidrawElement>>(
     element: TElement,
     updates: ElementUpdate<TElement>,
@@ -6930,7 +6947,7 @@ class App extends React.Component<AppProps, AppState> {
               y: scenePointerY,
             },
           });
-          this.setState({ suggestedBinding: null, startBoundElement: null });
+          this.setState({ suggestedBinding: null });
           if (!this.state.activeTool.locked) {
             resetCursor(this.interactiveCanvas);
             this.setState((prevState) => ({
@@ -7574,7 +7591,6 @@ class App extends React.Component<AppProps, AppState> {
         appState: {
           newElement: null,
           editingTextElement: null,
-          startBoundElement: null,
           suggestedBinding: null,
           selectedElementIds: makeNextSelectedElementIds(
             Object.keys(this.state.selectedElementIds)
@@ -8862,18 +8878,8 @@ class App extends React.Component<AppProps, AppState> {
       };
     });
 
-    const boundElement = getHoveredElementForBinding(
-      pointFrom<GlobalPoint>(
-        pointerDownState.origin.x,
-        pointerDownState.origin.y,
-      ),
-      this.scene.getNonDeletedElements(),
-      this.scene.getNonDeletedElementsMap(),
-    );
-
     this.setState({
       newElement: element,
-      startBoundElement: boundElement,
       suggestedBinding: null,
     });
   };
@@ -10726,7 +10732,7 @@ class App extends React.Component<AppProps, AppState> {
               sceneCoords,
             });
           }
-          this.setState({ suggestedBinding: null, startBoundElement: null });
+          this.setState({ suggestedBinding: null });
           if (!activeTool.locked) {
             resetCursor(this.interactiveCanvas);
             this.setState((prevState) => ({
@@ -10747,9 +10753,9 @@ class App extends React.Component<AppProps, AppState> {
               ),
             }));
           } else {
-            this.setState((prevState) => ({
+            this.setState({
               newElement: null,
-            }));
+            });
           }
           // so that the scene gets rendered again to display the newly drawn linear as well
           this.scene.triggerUpdate();

packages/excalidraw/components/LayerUI.tsx

@@ -650,8 +650,7 @@ const LayerUI = ({
 };
 
 const stripIrrelevantAppStateProps = (appState: AppState): UIAppState => {
-  const { startBoundElement, cursorButton, scrollX, scrollY, ...ret } =
+  const { cursorButton, scrollX, scrollY, ...ret } = appState;
-    appState;
   return ret;
 };
 

packages/excalidraw/css/styles.scss

@@ -814,6 +814,14 @@ body.excalidraw-cursor-resize * {
   .excalidraw__embeddable__outer {
     width: 100%;
     height: 100%;
+  }
+
+  .excalidraw__embeddable__content {
+    width: 100%;
+    height: 100%;
+    transform-origin: top left;
+
+    &,
     & > * {
       border-radius: var(--embeddable-radius);
     }

packages/excalidraw/data/restore.ts

@@ -96,6 +96,8 @@ type RestoredAppState = Omit<
   "offsetTop" | "offsetLeft" | "width" | "height"
 >;
 
+const MAX_ARROW_PX = 75_000;
+
 export const AllowedExcalidrawActiveTools: Record<
   AppState["activeTool"]["type"],
   boolean
@@ -467,8 +469,8 @@ export const restoreElement = (
         element.endArrowhead === undefined
           ? "arrow"
           : normalizeArrowhead(element.endArrowhead);
-      const x: number | undefined = element.x;
+      const x = element.x as number | undefined;
-      const y: number | undefined = element.y;
+      const y = element.y as number | undefined;
       const points: readonly LocalPoint[] | undefined = // migrate old arrow model to new one
         !Array.isArray(element.points) || element.points.length < 2
           ? [pointFrom(0, 0), pointFrom(element.width, element.height)]
@@ -493,8 +495,8 @@ export const restoreElement = (
         startArrowhead,
         endArrowhead,
         points,
-        x,
+        x: x ?? 0,
-        y,
+        y: y ?? 0,
         elbowed: (element as ExcalidrawArrowElement).elbowed,
         ...getSizeFromPoints(points),
       };
@@ -513,12 +515,44 @@ export const restoreElement = (
           })
         : restoreElementWithProperties(element as ExcalidrawArrowElement, base);
 
-      return {
+      const normalizedRestoredElement = {
         ...restoredElement,
         ...LinearElementEditor.getNormalizeElementPointsAndCoords(
           restoredElement,
         ),
       };
+
+      // Last resort fix for extremely large arrows
+      if (
+        normalizedRestoredElement.width > MAX_ARROW_PX ||
+        normalizedRestoredElement.height > MAX_ARROW_PX
+      ) {
+        console.error(
+          `Removing extremely large arrow ${
+            normalizedRestoredElement.id
+          } (type: ${
+            isElbowArrow(normalizedRestoredElement) ? "elbow" : "simple"
+          }, width: ${normalizedRestoredElement.width}, height: ${
+            normalizedRestoredElement.height
+          }, x: ${normalizedRestoredElement.x}, y: ${
+            normalizedRestoredElement.y
+          })`,
+        );
+        return {
+          ...normalizedRestoredElement,
+          x: 0,
+          y: 0,
+          width: 100,
+          height: 100,
+          points: [
+            pointFrom<LocalPoint>(0, 0),
+            pointFrom<LocalPoint>(100, 100),
+          ],
+          isDeleted: true,
+        };
+      }
+
+      return normalizedRestoredElement;
     }
 
     // generic elements
@@ -666,6 +700,7 @@ export const restoreElements = <T extends ExcalidrawElement>(
   const existingElementsMap = existingElements
     ? arrayToMap(existingElements)
     : null;
+
   const restoredElements = syncInvalidIndices(
     (targetElements || []).reduce((elements, element) => {
       // filtering out selection, which is legacy, no longer kept in elements,
@@ -762,7 +797,7 @@ export const restoreElements = <T extends ExcalidrawElement>(
     }
   }
 
-  // NOTE (mtolmacs): Temporary fix for extremely large arrows
+  // NOTE (mtolmacs): Temporary fix for invalid/self-bound elbow arrows
   // Need to iterate again so we have attached text nodes in elementsMap
   return restoredElements.map((element) => {
     if (

packages/excalidraw/history.ts

@@ -87,22 +87,10 @@ export class HistoryChangedEvent {
   ) {}
 }
 
-export type HistoryBeforeRecordListener = (delta: StoreDelta) => void;
-export type HistoryPerformDirection = "undo" | "redo";
-export type HistoryEffectiveDeltaResolverContext = {
-  direction: HistoryPerformDirection;
-};
-export type HistoryEffectiveDeltaResolver = (
-  delta: HistoryDelta,
-  context: HistoryEffectiveDeltaResolverContext,
-) => HistoryDelta;
-
 export class History {
   public readonly onHistoryChangedEmitter = new Emitter<
     [HistoryChangedEvent]
   >();
-  private readonly onBeforeRecordEmitter = new Emitter<[StoreDelta]>();
-  private effectiveDeltaResolver: HistoryEffectiveDeltaResolver | null = null;
 
   public readonly undoStack: HistoryDelta[] = [];
   public readonly redoStack: HistoryDelta[] = [];
@@ -117,20 +105,6 @@ export class History {
 
   constructor(private readonly store: Store) {}
 
-  /**
-   * Registers a hook that runs before a durable delta is converted
-   * into a history entry.
-   */
-  public onBeforeRecord(callback: HistoryBeforeRecordListener) {
-    return this.onBeforeRecordEmitter.on(callback);
-  }
-
-  public setEffectiveDeltaResolver(
-    resolver: HistoryEffectiveDeltaResolver | null,
-  ) {
-    this.effectiveDeltaResolver = resolver;
-  }
-
   public clear() {
     this.undoStack.length = 0;
     this.redoStack.length = 0;
@@ -145,8 +119,6 @@ export class History {
       return;
     }
 
-    this.onBeforeRecordEmitter.trigger(delta);
-
     // construct history entry, so once it's emitted, it's not recorded again
     const historyDelta = HistoryDelta.inverse(delta);
 
@@ -159,14 +131,15 @@ export class History {
       this.redoStack.length = 0;
     }
 
-    this.emitHistoryChanged();
+    this.onHistoryChangedEmitter.trigger(
+      new HistoryChangedEvent(this.isUndoStackEmpty, this.isRedoStackEmpty),
+    );
   }
 
   public undo(elements: SceneElementsMap, appState: AppState) {
     return this.perform(
       elements,
       appState,
-      "undo",
       () => History.pop(this.undoStack),
       (entry: HistoryDelta) => History.push(this.redoStack, entry),
     );
@@ -176,7 +149,6 @@ export class History {
     return this.perform(
       elements,
       appState,
-      "redo",
       () => History.pop(this.redoStack),
       (entry: HistoryDelta) => History.push(this.undoStack, entry),
     );
@@ -185,7 +157,6 @@ export class History {
   private perform(
     elements: SceneElementsMap,
     appState: AppState,
-    direction: HistoryPerformDirection,
     pop: () => HistoryDelta | null,
     push: (entry: HistoryDelta) => void,
   ): [SceneElementsMap, AppState] | void {
@@ -206,15 +177,9 @@ export class History {
 
       // iterate through the history entries in case they result in no visible changes
       while (historyDelta) {
-        // Roundtrip invariant: whichever delta we execute must be the one that
-        // continues through applyLatestChanges -> inverse -> opposite stack.
-        let entryToPush = historyDelta;
         try {
-          const effectiveDelta = this.resolveEffectiveDelta(historyDelta, {
-            direction,
-          });
           [nextElements, nextAppState, containsVisibleChange] =
-            effectiveDelta.applyTo(nextElements, nextAppState, prevSnapshot);
+            historyDelta.applyTo(nextElements, nextAppState, prevSnapshot);
 
           const prevElements = prevSnapshot.elements;
           const nextSnapshot = prevSnapshot.maybeClone(
@@ -225,7 +190,7 @@ export class History {
 
           const change = StoreChange.create(prevSnapshot, nextSnapshot);
           const delta = HistoryDelta.applyLatestChanges(
-            effectiveDelta,
+            historyDelta,
             prevElements,
             nextElements,
           );
@@ -238,12 +203,12 @@ export class History {
               delta,
             });
 
-            entryToPush = delta;
+            historyDelta = delta;
           }
 
           prevSnapshot = nextSnapshot;
         } finally {
-          push(entryToPush);
+          push(historyDelta);
         }
 
         if (containsVisibleChange) {
@@ -257,16 +222,12 @@ export class History {
     } finally {
       // trigger the history change event before returning completely
       // also trigger it just once, no need doing so on each entry
-      this.emitHistoryChanged();
+      this.onHistoryChangedEmitter.trigger(
+        new HistoryChangedEvent(this.isUndoStackEmpty, this.isRedoStackEmpty),
+      );
     }
   }
 
-  private emitHistoryChanged() {
-    this.onHistoryChangedEmitter.trigger(
-      new HistoryChangedEvent(this.isUndoStackEmpty, this.isRedoStackEmpty),
-    );
-  }
-
   private static pop(stack: HistoryDelta[]): HistoryDelta | null {
     if (!stack.length) {
       return null;
@@ -285,15 +246,4 @@ export class History {
     const inversedEntry = HistoryDelta.inverse(entry);
     return stack.push(inversedEntry);
   }
-
-  private resolveEffectiveDelta(
-    delta: HistoryDelta,
-    context: HistoryEffectiveDeltaResolverContext,
-  ): HistoryDelta {
-    if (!this.effectiveDeltaResolver) {
-      return delta;
-    }
-
-    return this.effectiveDeltaResolver(delta, context);
-  }
 }

packages/excalidraw/package.json

@@ -83,13 +83,13 @@
     "@codemirror/language": "^6.0.0",
     "@codemirror/state": "^6.0.0",
     "@codemirror/view": "^6.0.0",
+    "@lezer/highlight": "^1.0.0",
     "@excalidraw/common": "0.18.0",
     "@excalidraw/element": "0.18.0",
     "@excalidraw/laser-pointer": "1.3.1",
     "@excalidraw/math": "0.18.0",
     "@excalidraw/mermaid-to-excalidraw": "2.2.2",
     "@excalidraw/random-username": "1.1.0",
-    "@lezer/highlight": "^1.0.0",
     "browser-fs-access": "0.38.0",
     "canvas-roundrect-polyfill": "0.0.1",
     "clsx": "1.1.1",

packages/excalidraw/renderer/renderSnaps.ts

@@ -19,8 +19,6 @@ export const renderSnaps = (
   }
 
   // in dark mode, we need to adjust the color to account for color inversion.
-  // Don't change if zen mode, because we draw only crosses, we want the
-  // colors to be more visible
   const snapColor =
     appState.theme === THEME.LIGHT || appState.zenModeEnabled
       ? SNAP_COLOR_LIGHT

packages/excalidraw/snapping.ts

@@ -39,6 +39,14 @@ import type {
 } from "./types";
 
 const SNAP_DISTANCE = 8;
+// Keep snap candidates with effectively identical offsets together. This needs
+// to be wider than the 6-decimal rounding quantum to absorb JS floating-point
+// noise around values like 4 and 4.000001.
+const SNAP_OFFSET_TOLERANCE = 0.00001;
+// Point snaps can come from both nearby and distant references within snap
+// distance. If their visual distances have a large break, prefer the nearest
+// cluster before comparing offsets.
+const SNAP_REFERENCE_CLUSTER_BREAK_DISTANCE = 200;
 
 // do not comput more gaps per axis than this limit
 // TODO increase or remove once we optimize
@@ -49,16 +57,51 @@ export const getSnapDistance = (zoomValue: number) => {
   return SNAP_DISTANCE / zoomValue;
 };
 
+/**
+ * Keeps the cluster threshold visually stable across zoom levels.
+ */
+const getSnapReferenceClusterBreakDistance = (zoomValue: number) => {
+  return SNAP_REFERENCE_CLUSTER_BREAK_DISTANCE / zoomValue;
+};
+
 type Vector2D = {
   x: number;
   y: number;
 };
 
 type PointPair = [GlobalPoint, GlobalPoint];
+type SnapPointType = "outer" | "center";
+type SnapSourceId = string;
+
+const SELECTION_SNAP_SOURCE_ID = "selection";
+
+// Snap source ids let us filter redundant snaplines only within one
+// selection-to-reference relationship, without mixing separate reference groups.
+// For example, "selection->rectA" may collapse to its outermost snaplines,
+// while "selection->rectB" still keeps its own independent snaplines.
+type SnapPoint = {
+  point: GlobalPoint;
+  type: SnapPointType;
+  snapSourceId: SnapSourceId;
+};
+
+const outerSnapPoint = (
+  point: GlobalPoint,
+  snapSourceId = SELECTION_SNAP_SOURCE_ID,
+): SnapPoint => ({
+  point,
+  type: "outer",
+  snapSourceId,
+});
 
 export type PointSnap = {
   type: "point";
   points: PointPair;
+  pointTypes: [SnapPointType, SnapPointType];
+  snapSourceIds: [SnapSourceId, SnapSourceId];
+  // Distance along the rendered snapline, used to group visually nearby
+  // references before choosing which point snaps should win.
+  visualDistance: number;
   offset: number;
 };
 
@@ -120,14 +163,14 @@ export type SnapLine = PointSnapLine | GapSnapLine | PointerSnapLine;
 // -----------------------------------------------------------------------------
 
 export class SnapCache {
-  private static referenceSnapPoints: GlobalPoint[] | null = null;
+  private static referenceSnapPoints: SnapPoint[] | null = null;
 
   private static visibleGaps: {
     verticalGaps: Gap[];
     horizontalGaps: Gap[];
   } | null = null;
 
-  public static setReferenceSnapPoints = (snapPoints: GlobalPoint[] | null) => {
+  public static setReferenceSnapPoints = (snapPoints: SnapPoint[] | null) => {
     SnapCache.referenceSnapPoints = snapPoints;
   };
 
@@ -195,6 +238,17 @@ export const areRoughlyEqual = (a: number, b: number, precision = 0.01) => {
   return Math.abs(a - b) <= precision;
 };
 
+/**
+ * Keeps nearly identical snap offsets in the same winner set. This prevents
+ * snapline flicker when rounded geometry differs by a tiny floating-point tail.
+ */
+const isWithinSnapOffset = (offset: number, minOffset: number) => {
+  return (
+    Math.abs(offset) <= minOffset ||
+    areRoughlyEqual(Math.abs(offset), minOffset, SNAP_OFFSET_TOLERANCE)
+  );
+};
+
 export const getElementsCorners = (
   elements: ExcalidrawElement[],
   elementsMap: ElementsMap,
@@ -312,18 +366,81 @@ export const getElementsCorners = (
   return result.map((p) => pointFrom(round(p[0]), round(p[1])));
 };
 
+const getElementsSnapPoints = (
+  elements: ExcalidrawElement[],
+  elementsMap: ElementsMap,
+  options: Parameters<typeof getElementsCorners>[2] = {},
+  snapSourceId = SELECTION_SNAP_SOURCE_ID,
+): SnapPoint[] => {
+  const points = getElementsCorners(elements, elementsMap, options);
+  // getElementsCorners() appends the center point last unless omitCenter is set.
+  const hasCenterPoint = !options.omitCenter && points.length > 0;
+
+  return points.map((point, index) => ({
+    point,
+    type: hasCenterPoint && index === points.length - 1 ? "center" : "outer",
+    snapSourceId,
+  }));
+};
+
+/**
+ * Builds a stable identity for one snap reference group. Sorting keeps grouped
+ * elements represented by the same snap source id regardless of element order.
+ */
+const getSnapSourceId = (elements: ExcalidrawElement[]) => {
+  return elements
+    .map((element) => element.id)
+    .sort()
+    .join(",");
+};
+
+/**
+ * Finds frames that the current selection already belongs to. Their children
+ * are still valid snap references; children of unrelated frames are not.
+ */
+const getSelectedFrameIdsForSnapping = (
+  selectedElements: readonly ExcalidrawElement[],
+) => {
+  const selectedFrameIds = new Set<ExcalidrawElement["id"]>();
+
+  for (const element of selectedElements) {
+    if (element.frameId) {
+      selectedFrameIds.add(element.frameId);
+    }
+  }
+
+  return selectedFrameIds;
+};
+
+/**
+ * Frame children are only snap references when the dragged selection is inside
+ * the same frame. This avoids snapping external elements to internals of a
+ * framed diagram.
+ */
+const canUseElementAsSnapReference = (
+  element: NonDeletedExcalidrawElement,
+  selectedFrameIds: Set<ExcalidrawElement["id"]>,
+) => {
+  return !element.frameId || selectedFrameIds.has(element.frameId);
+};
+
 const getReferenceElements = (
   elements: readonly NonDeletedExcalidrawElement[],
   selectedElements: NonDeletedExcalidrawElement[],
   appState: AppState,
   elementsMap: ElementsMap,
-) =>
+) => {
-  getVisibleAndNonSelectedElements(
+  const selectedFrameIds = getSelectedFrameIdsForSnapping(selectedElements);
+
+  return getVisibleAndNonSelectedElements(
     elements,
     selectedElements,
     appState,
     elementsMap,
-  );
+  ).filter((element) => {
+    return canUseElementAsSnapReference(element, selectedFrameIds);
+  });
+};
 
 export const getVisibleGaps = (
   elements: readonly NonDeletedExcalidrawElement[],
@@ -482,7 +599,10 @@ const getGapSnaps = (
       const centerOffset = round(gapMidX - centerX);
       const gapIsLargerThanSelection = gap.length > maxX - minX;
 
-      if (gapIsLargerThanSelection && Math.abs(centerOffset) <= minOffset.x) {
+      if (
+        gapIsLargerThanSelection &&
+        isWithinSnapOffset(centerOffset, minOffset.x)
+      ) {
         if (Math.abs(centerOffset) < minOffset.x) {
           nearestSnapsX.length = 0;
         }
@@ -504,7 +624,7 @@ const getGapSnaps = (
       const distanceToEndElementX = minX - endMaxX;
       const sideOffsetRight = round(gap.length - distanceToEndElementX);
 
-      if (Math.abs(sideOffsetRight) <= minOffset.x) {
+      if (isWithinSnapOffset(sideOffsetRight, minOffset.x)) {
         if (Math.abs(sideOffsetRight) < minOffset.x) {
           nearestSnapsX.length = 0;
         }
@@ -525,7 +645,7 @@ const getGapSnaps = (
       const distanceToStartElementX = startMinX - maxX;
       const sideOffsetLeft = round(distanceToStartElementX - gap.length);
 
-      if (Math.abs(sideOffsetLeft) <= minOffset.x) {
+      if (isWithinSnapOffset(sideOffsetLeft, minOffset.x)) {
         if (Math.abs(sideOffsetLeft) < minOffset.x) {
           nearestSnapsX.length = 0;
         }
@@ -551,7 +671,10 @@ const getGapSnaps = (
       const centerOffset = round(gapMidY - centerY);
       const gapIsLargerThanSelection = gap.length > maxY - minY;
 
-      if (gapIsLargerThanSelection && Math.abs(centerOffset) <= minOffset.y) {
+      if (
+        gapIsLargerThanSelection &&
+        isWithinSnapOffset(centerOffset, minOffset.y)
+      ) {
         if (Math.abs(centerOffset) < minOffset.y) {
           nearestSnapsY.length = 0;
         }
@@ -573,7 +696,7 @@ const getGapSnaps = (
       const distanceToStartElementY = startMinY - maxY;
       const sideOffsetTop = round(distanceToStartElementY - gap.length);
 
-      if (Math.abs(sideOffsetTop) <= minOffset.y) {
+      if (isWithinSnapOffset(sideOffsetTop, minOffset.y)) {
         if (Math.abs(sideOffsetTop) < minOffset.y) {
           nearestSnapsY.length = 0;
         }
@@ -594,7 +717,7 @@ const getGapSnaps = (
       const distanceToEndElementY = round(minY - endMaxY);
       const sideOffsetBottom = gap.length - distanceToEndElementY;
 
-      if (Math.abs(sideOffsetBottom) <= minOffset.y) {
+      if (isWithinSnapOffset(sideOffsetBottom, minOffset.y)) {
         if (Math.abs(sideOffsetBottom) < minOffset.y) {
           nearestSnapsY.length = 0;
         }
@@ -613,6 +736,102 @@ const getGapSnaps = (
   }
 };
 
+/**
+ * Narrows point snaps to the nearest visual cluster, then keeps the best offset
+ * inside that cluster. If all references look continuous, this preserves the
+ * old smallest-offset behavior.
+ */
+const filterPointSnapsToNearestCluster = (
+  snaps: Snaps,
+  clusterBreakDistance: number,
+) => {
+  const pointSnaps = snaps.filter(
+    (snap): snap is PointSnap => snap.type === "point",
+  );
+
+  if (pointSnaps.length < 2) {
+    return;
+  }
+
+  const snapsByOffset = new Map<number, PointSnap[]>();
+
+  for (const snap of pointSnaps) {
+    const offset = round(snap.offset);
+    const offsetSnaps = snapsByOffset.get(offset) ?? [];
+    offsetSnaps.push(snap);
+    snapsByOffset.set(offset, offsetSnaps);
+  }
+
+  const keptPointSnaps = new Set<PointSnap>();
+  const offsetGroups = Array.from(snapsByOffset.entries()).map(
+    ([offset, offsetSnaps]) => ({
+      offset,
+      snaps: offsetSnaps,
+      visualDistance: Math.min(
+        ...offsetSnaps.map((snap) => snap.visualDistance),
+      ),
+    }),
+  );
+  const sortedOffsetGroups = offsetGroups
+    .slice()
+    .sort((a, b) => a.visualDistance - b.visualDistance);
+  let keepOffsetGroupsUntil = sortedOffsetGroups.length;
+
+  // Prefer a nearby reference cluster before comparing offset. If there is no
+  // clear distance break, this keeps all offsets and falls back to the old
+  // smallest-offset behavior.
+  for (let i = 1; i < sortedOffsetGroups.length; i++) {
+    const distanceGap =
+      sortedOffsetGroups[i].visualDistance -
+      sortedOffsetGroups[i - 1].visualDistance;
+
+    if (distanceGap > clusterBreakDistance) {
+      keepOffsetGroupsUntil = i;
+      break;
+    }
+  }
+
+  const nearestOffsetGroups = sortedOffsetGroups.slice(
+    0,
+    keepOffsetGroupsUntil,
+  );
+  const minOffset = Math.min(
+    ...nearestOffsetGroups.map(({ offset }) => Math.abs(offset)),
+  );
+  const selectedOffsets = nearestOffsetGroups
+    .filter(({ offset }) =>
+      areRoughlyEqual(Math.abs(offset), minOffset, SNAP_OFFSET_TOLERANCE),
+    )
+    .map(({ offset }) => offset);
+
+  for (const offsetSnaps of snapsByOffset.values()) {
+    if (
+      !selectedOffsets.some((offset) =>
+        areRoughlyEqual(
+          round(offsetSnaps[0].offset),
+          offset,
+          SNAP_OFFSET_TOLERANCE,
+        ),
+      )
+    ) {
+      continue;
+    }
+
+    offsetSnaps.forEach((snap) => keptPointSnaps.add(snap));
+  }
+
+  let writeIndex = 0;
+
+  for (const snap of snaps) {
+    if (snap.type !== "point" || keptPointSnaps.has(snap)) {
+      snaps[writeIndex] = snap;
+      writeIndex++;
+    }
+  }
+
+  snaps.length = writeIndex;
+};
+
 export const getReferenceSnapPoints = (
   elements: readonly NonDeletedExcalidrawElement[],
   selectedElements: ExcalidrawElement[],
@@ -630,12 +849,24 @@ export const getReferenceSnapPoints = (
       (elementsGroup) =>
         !(elementsGroup.length === 1 && isBoundToContainer(elementsGroup[0])),
     )
-    .flatMap((elementGroup) => getElementsCorners(elementGroup, elementsMap));
+    .flatMap((elementGroup) =>
+      getElementsSnapPoints(
+        elementGroup,
+        elementsMap,
+        {},
+        getSnapSourceId(elementGroup),
+      ),
+    );
 };
 
+/**
+ * Collects point snaps within snap distance. Unlike gap snaps, point snaps first
+ * go through visual-cluster filtering so a nearby reference can beat a slightly
+ * better offset from a far-away reference.
+ */
 const getPointSnaps = (
   selectedElements: ExcalidrawElement[],
-  selectionSnapPoints: GlobalPoint[],
+  selectionSnapPoints: SnapPoint[],
   app: AppClassProperties,
   event: KeyboardModifiersObject,
   nearestSnapsX: Snaps,
@@ -654,39 +885,62 @@ const getPointSnaps = (
   if (referenceSnapPoints) {
     for (const thisSnapPoint of selectionSnapPoints) {
       for (const otherSnapPoint of referenceSnapPoints) {
-        const offsetX = otherSnapPoint[0] - thisSnapPoint[0];
+        const offsetX = otherSnapPoint.point[0] - thisSnapPoint.point[0];
-        const offsetY = otherSnapPoint[1] - thisSnapPoint[1];
+        const offsetY = otherSnapPoint.point[1] - thisSnapPoint.point[1];
-
-        if (Math.abs(offsetX) <= minOffset.x) {
-          if (Math.abs(offsetX) < minOffset.x) {
-            nearestSnapsX.length = 0;
-          }
 
+        if (isWithinSnapOffset(offsetX, minOffset.x)) {
           nearestSnapsX.push({
             type: "point",
-            points: [thisSnapPoint, otherSnapPoint],
+            points: [thisSnapPoint.point, otherSnapPoint.point],
+            pointTypes: [thisSnapPoint.type, otherSnapPoint.type],
+            snapSourceIds: [
+              thisSnapPoint.snapSourceId,
+              otherSnapPoint.snapSourceId,
+            ],
+            visualDistance: Math.abs(
+              otherSnapPoint.point[1] - thisSnapPoint.point[1],
+            ),
             offset: offsetX,
           });
-
-          minOffset.x = Math.abs(offsetX);
         }
 
-        if (Math.abs(offsetY) <= minOffset.y) {
+        if (isWithinSnapOffset(offsetY, minOffset.y)) {
-          if (Math.abs(offsetY) < minOffset.y) {
-            nearestSnapsY.length = 0;
-          }
-
           nearestSnapsY.push({
             type: "point",
-            points: [thisSnapPoint, otherSnapPoint],
+            points: [thisSnapPoint.point, otherSnapPoint.point],
+            pointTypes: [thisSnapPoint.type, otherSnapPoint.type],
+            snapSourceIds: [
+              thisSnapPoint.snapSourceId,
+              otherSnapPoint.snapSourceId,
+            ],
+            visualDistance: Math.abs(
+              otherSnapPoint.point[0] - thisSnapPoint.point[0],
+            ),
             offset: offsetY,
           });
-
-          minOffset.y = Math.abs(offsetY);
         }
       }
     }
   }
+
+  const clusterBreakDistance = getSnapReferenceClusterBreakDistance(
+    app.state.zoom.value,
+  );
+
+  filterPointSnapsToNearestCluster(nearestSnapsX, clusterBreakDistance);
+  filterPointSnapsToNearestCluster(nearestSnapsY, clusterBreakDistance);
+
+  if (nearestSnapsX.length > 0) {
+    minOffset.x = Math.min(
+      ...nearestSnapsX.map((snap) => Math.abs(snap.offset)),
+    );
+  }
+
+  if (nearestSnapsY.length > 0) {
+    minOffset.y = Math.min(
+      ...nearestSnapsY.map((snap) => Math.abs(snap.offset)),
+    );
+  }
 };
 
 export const snapDraggedElements = (
@@ -720,7 +974,7 @@ export const snapDraggedElements = (
     y: snapDistance,
   };
 
-  const selectionPoints = getElementsCorners(selectedElements, elementsMap, {
+  const selectionPoints = getElementsSnapPoints(selectedElements, elementsMap, {
     dragOffset,
   });
 
@@ -770,7 +1024,7 @@ export const snapDraggedElements = (
 
   getPointSnaps(
     selectedElements,
-    getElementsCorners(selectedElements, elementsMap, {
+    getElementsSnapPoints(selectedElements, elementsMap, {
       dragOffset: newDragOffset,
     }),
     app,
@@ -825,12 +1079,185 @@ const dedupePoints = (points: GlobalPoint[]): GlobalPoint[] => {
   return Array.from(map.values());
 };
 
+// Point snaplines are collected from every winning point snap first. Multiple
+// snap source pairs can collapse to the same rendered line, so candidates keep
+// source-pair metadata until redundant center and inner outer lines are removed.
+type PointSnapLineSourcePair = {
+  snapSourcePairKey: string;
+  pointType: SnapPointType;
+};
+
+type PointSnapLineCandidate = PointSnapLine & {
+  sourcePairs: PointSnapLineSourcePair[];
+};
+
+type PointSnapLineBucket = {
+  points: GlobalPoint[];
+  sourcePairs: PointSnapLineSourcePair[];
+};
+
+type OuterSnapLineCoordinateRange = {
+  count: number;
+  min: number;
+  max: number;
+};
+
+/**
+ * Describes which snap source pair produced a rendered point snapline, so later
+ * filtering can reason about redundancy without mixing unrelated references.
+ * Only center-to-center snaps count as center snaplines; a center-to-outer snap
+ * still explains an outer edge or midpoint alignment.
+ */
+const getPointSnapLineSourcePair = (
+  snap: PointSnap,
+): PointSnapLineSourcePair => {
+  return {
+    snapSourcePairKey: snap.snapSourceIds.join("->"),
+    pointType: snap.pointTypes.every((pointType) => pointType === "center")
+      ? "center"
+      : "outer",
+  };
+};
+
+/**
+ * Builds each snap source pair's outer coordinate range. Center snaplines use
+ * this range to decide whether the surrounding outer lines already explain
+ * them, and outer snaplines use it to keep only the two extremes.
+ */
+const getOuterCoordinateRangesBySnapSourcePairKey = (
+  snapLines: PointSnapLineCandidate[],
+  getCoordinate: (snapLine: PointSnapLine) => number,
+) => {
+  const ranges = new Map<string, OuterSnapLineCoordinateRange>();
+
+  for (const snapLine of snapLines) {
+    const coordinate = getCoordinate(snapLine);
+
+    for (const sourcePair of snapLine.sourcePairs) {
+      if (sourcePair.pointType === "center") {
+        continue;
+      }
+
+      const range = ranges.get(sourcePair.snapSourcePairKey);
+
+      ranges.set(sourcePair.snapSourcePairKey, {
+        count: (range?.count ?? 0) + 1,
+        min: range ? Math.min(range.min, coordinate) : coordinate,
+        max: range ? Math.max(range.max, coordinate) : coordinate,
+      });
+    }
+  }
+
+  return ranges;
+};
+
+/**
+ * A center snapline is redundant when outer snaplines from the same snap source
+ * pair exist on both sides, because the outer lines already imply center
+ * alignment.
+ */
+const isRedundantCenterSnapLine = (
+  coordinate: number,
+  outerCoordinateRange?: OuterSnapLineCoordinateRange,
+) => {
+  if (!outerCoordinateRange) {
+    return false;
+  }
+
+  return (
+    outerCoordinateRange.min < coordinate &&
+    outerCoordinateRange.max > coordinate
+  );
+};
+
+/**
+ * When more than two outer snaplines come from the same snap source pair, the
+ * inner ones are redundant; the two extremes communicate the same shape
+ * alignment.
+ */
+const isRedundantOuterSnapLine = (
+  coordinate: number,
+  outerCoordinateRange?: OuterSnapLineCoordinateRange,
+) => {
+  if (!outerCoordinateRange || outerCoordinateRange.count <= 2) {
+    return false;
+  }
+
+  return (
+    coordinate !== outerCoordinateRange.min &&
+    coordinate !== outerCoordinateRange.max
+  );
+};
+
+/**
+ * Keeps a visual snapline if at least one snap source pair represented by the
+ * line still needs it. This matters when multiple snap source pairs collapse to
+ * the same rendered coordinate.
+ */
+const isPointSnapLineNeededBySourcePair = (
+  sourcePair: PointSnapLineSourcePair,
+  coordinate: number,
+  outerCoordinateRangesBySnapSourcePairKey: Map<
+    string,
+    OuterSnapLineCoordinateRange
+  >,
+) => {
+  const outerCoordinateRange = outerCoordinateRangesBySnapSourcePairKey.get(
+    sourcePair.snapSourcePairKey,
+  );
+
+  if (sourcePair.pointType === "center") {
+    return !isRedundantCenterSnapLine(coordinate, outerCoordinateRange);
+  }
+
+  return !isRedundantOuterSnapLine(coordinate, outerCoordinateRange);
+};
+
+/**
+ * Removes point snaplines that are visually redundant, while preserving any line
+ * that is still needed by at least one snap source pair represented on that
+ * line.
+ */
+const filterRedundantPointSnapLines = (
+  snapLines: PointSnapLineCandidate[],
+  getCoordinate: (snapLine: PointSnapLine) => number,
+): PointSnapLine[] => {
+  if (snapLines.length < 3) {
+    return snapLines.map(({ sourcePairs, ...snapLine }) => snapLine);
+  }
+
+  // Track outer-line ranges per snap source pair. The same visual snapline can
+  // be produced by multiple snap source pairs, so a line is removed only when
+  // every pair represented by that line considers it redundant.
+  const outerCoordinateRangesBySnapSourcePairKey =
+    getOuterCoordinateRangesBySnapSourcePairKey(snapLines, getCoordinate);
+
+  return snapLines
+    .filter((snapLine) => {
+      const coordinate = getCoordinate(snapLine);
+
+      return snapLine.sourcePairs.some((sourcePair) =>
+        isPointSnapLineNeededBySourcePair(
+          sourcePair,
+          coordinate,
+          outerCoordinateRangesBySnapSourcePairKey,
+        ),
+      );
+    })
+    .map(({ sourcePairs, ...snapLine }) => snapLine);
+};
+
+/**
+ * Merges point snaps that render on the same x/y coordinate, attaches their
+ * snap source pair metadata, then removes redundant center and inner outer
+ * lines.
+ */
 const createPointSnapLines = (
   nearestSnapsX: Snaps,
   nearestSnapsY: Snaps,
 ): PointSnapLine[] => {
-  const snapsX = {} as { [key: string]: GlobalPoint[] };
+  const snapsX = {} as { [key: string]: PointSnapLineBucket };
-  const snapsY = {} as { [key: string]: GlobalPoint[] };
+  const snapsY = {} as { [key: string]: PointSnapLineBucket };
 
   if (nearestSnapsX.length > 0) {
     for (const snap of nearestSnapsX) {
@@ -838,13 +1265,14 @@ const createPointSnapLines = (
         // key = thisPoint.x
         const key = round(snap.points[0][0]);
         if (!snapsX[key]) {
-          snapsX[key] = [];
+          snapsX[key] = { points: [], sourcePairs: [] };
         }
-        snapsX[key].push(
+        snapsX[key].points.push(
           ...snap.points.map((p) =>
             pointFrom<GlobalPoint>(round(p[0]), round(p[1])),
           ),
         );
+        snapsX[key].sourcePairs.push(getPointSnapLineSourcePair(snap));
       }
     }
   }
@@ -855,44 +1283,55 @@ const createPointSnapLines = (
         // key = thisPoint.y
         const key = round(snap.points[0][1]);
         if (!snapsY[key]) {
-          snapsY[key] = [];
+          snapsY[key] = { points: [], sourcePairs: [] };
         }
-        snapsY[key].push(
+        snapsY[key].points.push(
           ...snap.points.map((p) =>
             pointFrom<GlobalPoint>(round(p[0]), round(p[1])),
           ),
         );
+        snapsY[key].sourcePairs.push(getPointSnapLineSourcePair(snap));
       }
     }
   }
 
-  return Object.entries(snapsX)
+  const snapLinesX = Object.entries(snapsX).map(([key, snap]) => {
-    .map(([key, points]) => {
+    return {
-      return {
+      type: "points",
-        type: "points",
+      points: dedupePoints(
-        points: dedupePoints(
+        snap.points
-          points
+          .map((p) => {
-            .map((p) => {
+            return pointFrom<GlobalPoint>(Number(key), p[1]);
-              return pointFrom<GlobalPoint>(Number(key), p[1]);
+          })
-            })
+          .sort((a, b) => a[1] - b[1]),
-            .sort((a, b) => a[1] - b[1]),
+      ),
-        ),
+      sourcePairs: snap.sourcePairs,
-      } as PointSnapLine;
+    } as PointSnapLineCandidate;
-    })
+  });
-    .concat(
+
-      Object.entries(snapsY).map(([key, points]) => {
+  const snapLinesY = Object.entries(snapsY).map(([key, snap]) => {
-        return {
+    return {
-          type: "points",
+      type: "points",
-          points: dedupePoints(
+      points: dedupePoints(
-            points
+        snap.points
-              .map((p) => {
+          .map((p) => {
-                return pointFrom<GlobalPoint>(p[0], Number(key));
+            return pointFrom<GlobalPoint>(p[0], Number(key));
-              })
+          })
-              .sort((a, b) => a[0] - b[0]),
+          .sort((a, b) => a[0] - b[0]),
-          ),
+      ),
-        } as PointSnapLine;
+      sourcePairs: snap.sourcePairs,
-      }),
+    } as PointSnapLineCandidate;
-    );
+  });
+
+  return filterRedundantPointSnapLines(
+    snapLinesX,
+    (snapLine) => snapLine.points[0][0],
+  ).concat(
+    filterRedundantPointSnapLines(
+      snapLinesY,
+      (snapLine) => snapLine.points[0][1],
+    ),
+  );
 };
 
 const dedupeGapSnapLines = (gapSnapLines: GapSnapLine[]) => {
@@ -917,10 +1356,13 @@ const createGapSnapLines = (
   dragOffset: Vector2D,
   gapSnaps: GapSnap[],
 ): GapSnapLine[] => {
+  // Use the same rounded bounds as getGapSnaps(). Otherwise a gap snap can be
+  // accepted during snapping but skipped here because the raw bounds miss the
+  // reference gap overlap by a tiny floating-point delta.
   const [minX, minY, maxX, maxY] = getDraggedElementsBounds(
     selectedElements,
     dragOffset,
-  );
+  ).map((bound) => round(bound));
 
   const gapSnapLines: GapSnapLine[] = [];
 
@@ -1143,40 +1585,52 @@ export const snapResizingElements = (
     }
   }
 
-  const selectionSnapPoints: GlobalPoint[] = [];
+  const selectionSnapPoints: SnapPoint[] = [];
 
   if (transformHandle) {
     switch (transformHandle) {
       case "e": {
-        selectionSnapPoints.push(pointFrom(maxX, minY), pointFrom(maxX, maxY));
+        selectionSnapPoints.push(
+          outerSnapPoint(pointFrom(maxX, minY)),
+          outerSnapPoint(pointFrom(maxX, maxY)),
+        );
         break;
       }
       case "w": {
-        selectionSnapPoints.push(pointFrom(minX, minY), pointFrom(minX, maxY));
+        selectionSnapPoints.push(
+          outerSnapPoint(pointFrom(minX, minY)),
+          outerSnapPoint(pointFrom(minX, maxY)),
+        );
         break;
       }
       case "n": {
-        selectionSnapPoints.push(pointFrom(minX, minY), pointFrom(maxX, minY));
+        selectionSnapPoints.push(
+          outerSnapPoint(pointFrom(minX, minY)),
+          outerSnapPoint(pointFrom(maxX, minY)),
+        );
         break;
       }
       case "s": {
-        selectionSnapPoints.push(pointFrom(minX, maxY), pointFrom(maxX, maxY));
+        selectionSnapPoints.push(
+          outerSnapPoint(pointFrom(minX, maxY)),
+          outerSnapPoint(pointFrom(maxX, maxY)),
+        );
         break;
       }
       case "ne": {
-        selectionSnapPoints.push(pointFrom(maxX, minY));
+        selectionSnapPoints.push(outerSnapPoint(pointFrom(maxX, minY)));
         break;
       }
       case "nw": {
-        selectionSnapPoints.push(pointFrom(minX, minY));
+        selectionSnapPoints.push(outerSnapPoint(pointFrom(minX, minY)));
         break;
       }
       case "se": {
-        selectionSnapPoints.push(pointFrom(maxX, maxY));
+        selectionSnapPoints.push(outerSnapPoint(pointFrom(maxX, maxY)));
         break;
       }
       case "sw": {
-        selectionSnapPoints.push(pointFrom(minX, maxY));
+        selectionSnapPoints.push(outerSnapPoint(pointFrom(minX, maxY)));
         break;
       }
     }
@@ -1218,11 +1672,11 @@ export const snapResizingElements = (
     round(bound),
   );
 
-  const corners: GlobalPoint[] = [
+  const corners: SnapPoint[] = [
-    pointFrom(x1, y1),
+    outerSnapPoint(pointFrom(x1, y1)),
-    pointFrom(x1, y2),
+    outerSnapPoint(pointFrom(x1, y2)),
-    pointFrom(x2, y1),
+    outerSnapPoint(pointFrom(x2, y1)),
-    pointFrom(x2, y2),
+    outerSnapPoint(pointFrom(x2, y2)),
   ];
 
   getPointSnaps(
@@ -1258,8 +1712,8 @@ export const snapNewElement = (
     };
   }
 
-  const selectionSnapPoints: GlobalPoint[] = [
+  const selectionSnapPoints: SnapPoint[] = [
-    pointFrom(origin.x + dragOffset.x, origin.y + dragOffset.y),
+    outerSnapPoint(pointFrom(origin.x + dragOffset.x, origin.y + dragOffset.y)),
   ];
 
   const snapDistance = getSnapDistance(app.state.zoom.value);
@@ -1292,7 +1746,7 @@ export const snapNewElement = (
   nearestSnapsX.length = 0;
   nearestSnapsY.length = 0;
 
-  const corners = getElementsCorners([newElement], elementsMap, {
+  const corners = getElementsSnapPoints([newElement], elementsMap, {
     boundingBoxCorners: true,
     omitCenter: true,
   });

packages/excalidraw/tests/__snapshots__/contextmenu.test.tsx.snap

@@ -979,7 +979,6 @@ exports[`contextMenu element > right-clicking on a group should select whole gro
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -1173,7 +1172,6 @@ exports[`contextMenu element > selecting 'Add to library' in context menu adds e
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -1388,7 +1386,6 @@ exports[`contextMenu element > selecting 'Bring forward' in context menu brings
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -1720,7 +1717,6 @@ exports[`contextMenu element > selecting 'Bring to front' in context menu brings
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -2052,7 +2048,6 @@ exports[`contextMenu element > selecting 'Copy styles' in context menu copies st
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -2265,7 +2260,6 @@ exports[`contextMenu element > selecting 'Delete' in context menu deletes elemen
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -2509,7 +2503,6 @@ exports[`contextMenu element > selecting 'Duplicate' in context menu duplicates
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -2813,7 +2806,6 @@ exports[`contextMenu element > selecting 'Group selection' in context menu group
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -3181,7 +3173,6 @@ exports[`contextMenu element > selecting 'Paste styles' in context menu pastes s
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -3675,7 +3666,6 @@ exports[`contextMenu element > selecting 'Send backward' in context menu sends e
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -3999,7 +3989,6 @@ exports[`contextMenu element > selecting 'Send to back' in context menu sends el
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -4326,7 +4315,6 @@ exports[`contextMenu element > selecting 'Ungroup selection' in context menu ung
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -5612,7 +5600,6 @@ exports[`contextMenu element > shows 'Group selection' in context menu for multi
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -6832,7 +6819,6 @@ exports[`contextMenu element > shows 'Ungroup selection' in context menu for gro
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -7786,7 +7772,6 @@ exports[`contextMenu element > shows context menu for canvas > [end of test] app
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -8786,7 +8771,6 @@ exports[`contextMenu element > shows context menu for element > [end of test] ap
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -9781,7 +9765,6 @@ exports[`contextMenu element > shows context menu for element > [end of test] ap
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,

packages/excalidraw/tests/__snapshots__/history.test.tsx.snap

@@ -1293,7 +1293,6 @@ exports[`history > multiplayer undo/redo > conflicts in arrows and their bindabl
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -1654,7 +1653,6 @@ exports[`history > multiplayer undo/redo > conflicts in arrows and their bindabl
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -2017,7 +2015,6 @@ exports[`history > multiplayer undo/redo > conflicts in arrows and their bindabl
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -2280,7 +2277,40 @@ exports[`history > multiplayer undo/redo > conflicts in arrows and their bindabl
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
+  "startBoundElement": {
+    "angle": 0,
+    "backgroundColor": "transparent",
+    "boundElements": [
+      {
+        "id": "id4",
+        "type": "arrow",
+      },
+    ],
+    "customData": undefined,
+    "fillStyle": "solid",
+    "frameId": null,
+    "groupIds": [],
+    "height": 100,
+    "id": "id0",
+    "index": "a0",
+    "isDeleted": false,
+    "link": null,
+    "locked": false,
+    "opacity": 100,
+    "roughness": 1,
+    "roundness": null,
+    "seed": 1,
+    "strokeColor": "#1e1e1e",
+    "strokeStyle": "solid",
+    "strokeWidth": 2,
+    "type": "rectangle",
+    "updated": 1,
+    "version": 3,
+    "versionNonce": 493213705,
+    "width": 100,
+    "x": -100,
+    "y": -50,
+  },
   "stats": {
     "open": false,
     "panels": 3,
@@ -2735,7 +2765,6 @@ exports[`history > multiplayer undo/redo > conflicts in bound text elements and
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -3039,7 +3068,6 @@ exports[`history > multiplayer undo/redo > conflicts in bound text elements and
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -3359,7 +3387,6 @@ exports[`history > multiplayer undo/redo > conflicts in bound text elements and
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -3654,7 +3681,6 @@ exports[`history > multiplayer undo/redo > conflicts in bound text elements and
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -3941,7 +3967,6 @@ exports[`history > multiplayer undo/redo > conflicts in bound text elements and
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -4177,7 +4202,6 @@ exports[`history > multiplayer undo/redo > conflicts in bound text elements and
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -4435,7 +4459,6 @@ exports[`history > multiplayer undo/redo > conflicts in bound text elements and
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -4707,7 +4730,6 @@ exports[`history > multiplayer undo/redo > conflicts in bound text elements and
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -4937,7 +4959,6 @@ exports[`history > multiplayer undo/redo > conflicts in bound text elements and
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -5167,7 +5188,6 @@ exports[`history > multiplayer undo/redo > conflicts in bound text elements and
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -5415,7 +5435,6 @@ exports[`history > multiplayer undo/redo > conflicts in bound text elements and
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -5672,7 +5691,6 @@ exports[`history > multiplayer undo/redo > conflicts in frames and their childre
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -5930,7 +5948,6 @@ exports[`history > multiplayer undo/redo > should iterate through the history wh
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -6260,7 +6277,6 @@ exports[`history > multiplayer undo/redo > should iterate through the history wh
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -6691,7 +6707,6 @@ exports[`history > multiplayer undo/redo > should iterate through the history wh
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -7072,7 +7087,6 @@ exports[`history > multiplayer undo/redo > should iterate through the history wh
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -7667,7 +7681,6 @@ exports[`history > multiplayer undo/redo > should iterate through the history wh
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -7898,7 +7911,6 @@ exports[`history > multiplayer undo/redo > should iterate through the history wh
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -8251,7 +8263,6 @@ exports[`history > multiplayer undo/redo > should iterate through the history wh
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -8610,7 +8621,6 @@ exports[`history > multiplayer undo/redo > should not let remote changes to inte
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -9011,7 +9021,6 @@ exports[`history > multiplayer undo/redo > should not let remote changes to inte
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -9293,7 +9302,6 @@ exports[`history > multiplayer undo/redo > should not let remote changes to inte
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -9558,7 +9566,6 @@ exports[`history > multiplayer undo/redo > should not override remote changes on
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -9824,7 +9831,6 @@ exports[`history > multiplayer undo/redo > should not override remote changes on
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -10058,7 +10064,6 @@ exports[`history > multiplayer undo/redo > should override remotely added groups
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -10671,7 +10676,6 @@ exports[`history > multiplayer undo/redo > should redistribute deltas when eleme
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -10911,7 +10915,6 @@ exports[`history > multiplayer undo/redo > should redraw arrows on undo > [end o
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -11836,7 +11839,6 @@ exports[`history > multiplayer undo/redo > should update history entries after r
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -12095,7 +12097,6 @@ exports[`history > singleplayer undo/redo > remounting undo/redo buttons should
   "showHyperlinkPopup": false,
   "showWelcomeScreen": false,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -12333,7 +12334,6 @@ exports[`history > singleplayer undo/redo > should clear the redo stack on eleme
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -12569,7 +12569,6 @@ exports[`history > singleplayer undo/redo > should create entry when selecting f
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -12966,7 +12965,6 @@ exports[`history > singleplayer undo/redo > should create new history entry on e
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -13174,7 +13172,6 @@ exports[`history > singleplayer undo/redo > should create new history entry on e
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -13386,7 +13383,6 @@ exports[`history > singleplayer undo/redo > should create new history entry on i
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -13685,7 +13681,6 @@ exports[`history > singleplayer undo/redo > should create new history entry on i
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -13984,7 +13979,6 @@ exports[`history > singleplayer undo/redo > should create new history entry on s
   "showHyperlinkPopup": false,
   "showWelcomeScreen": false,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -14229,7 +14223,6 @@ exports[`history > singleplayer undo/redo > should disable undo/redo buttons whe
   "showHyperlinkPopup": false,
   "showWelcomeScreen": false,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -14467,7 +14460,6 @@ exports[`history > singleplayer undo/redo > should end up with no history entry
   "showHyperlinkPopup": false,
   "showWelcomeScreen": false,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -14705,7 +14697,6 @@ exports[`history > singleplayer undo/redo > should iterate through the history w
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -14953,7 +14944,6 @@ exports[`history > singleplayer undo/redo > should not clear the redo stack on s
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -15286,7 +15276,6 @@ exports[`history > singleplayer undo/redo > should not collapse when applying co
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -15459,7 +15448,6 @@ exports[`history > singleplayer undo/redo > should not end up with history entry
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -15742,7 +15730,6 @@ exports[`history > singleplayer undo/redo > should not end up with history entry
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -16006,7 +15993,6 @@ exports[`history > singleplayer undo/redo > should not modify anything on unrela
   "showHyperlinkPopup": false,
   "showWelcomeScreen": false,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -16161,7 +16147,6 @@ exports[`history > singleplayer undo/redo > should not override appstate changes
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -16443,7 +16428,6 @@ exports[`history > singleplayer undo/redo > should support appstate name or view
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -20170,7 +20154,6 @@ exports[`history > singleplayer undo/redo > should support changes in elements'
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -20653,7 +20636,6 @@ exports[`history > singleplayer undo/redo > should support duplication of groups
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -21160,7 +21142,6 @@ exports[`history > singleplayer undo/redo > should support element creation, del
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,

packages/excalidraw/tests/__snapshots__/regressionTests.test.tsx.snap

@@ -106,7 +106,6 @@ exports[`given element A and group of elements B and given both are selected whe
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -535,7 +534,6 @@ exports[`given element A and group of elements B and given both are selected whe
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -943,7 +941,6 @@ exports[`regression tests > Cmd/Ctrl-click exclusively select element under poin
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -1510,7 +1507,6 @@ exports[`regression tests > Drags selected element when hitting only bounding bo
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -1723,7 +1719,6 @@ exports[`regression tests > adjusts z order when grouping > [end of test] appSta
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -2105,7 +2100,6 @@ exports[`regression tests > alt-drag duplicates an element > [end of test] appSt
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -2349,7 +2343,6 @@ exports[`regression tests > arrow keys > [end of test] appState 1`] = `
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -2532,7 +2525,6 @@ exports[`regression tests > can drag element that covers another element, while
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -2856,7 +2848,6 @@ exports[`regression tests > change the properties of a shape > [end of test] app
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -3114,7 +3105,6 @@ exports[`regression tests > click on an element and drag it > [dragged] appState
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -3356,7 +3346,6 @@ exports[`regression tests > click on an element and drag it > [end of test] appS
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -3593,7 +3582,6 @@ exports[`regression tests > click to select a shape > [end of test] appState 1`]
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -3853,7 +3841,6 @@ exports[`regression tests > click-drag to select a group > [end of test] appStat
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -4167,7 +4154,6 @@ exports[`regression tests > deleting last but one element in editing group shoul
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -4631,7 +4617,6 @@ exports[`regression tests > deselects group of selected elements on pointer down
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -4887,7 +4872,6 @@ exports[`regression tests > deselects group of selected elements on pointer up w
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -5191,7 +5175,6 @@ exports[`regression tests > deselects selected element on pointer down when poin
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -5372,7 +5355,6 @@ exports[`regression tests > deselects selected element, on pointer up, when clic
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -5573,7 +5555,6 @@ exports[`regression tests > double click to edit a group > [end of test] appStat
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -5971,7 +5952,6 @@ exports[`regression tests > drags selected elements from point inside common bou
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -7057,7 +7037,6 @@ exports[`regression tests > given a group of selected elements with an element t
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -7392,7 +7371,6 @@ exports[`regression tests > given a selected element A and a not selected elemen
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -7671,7 +7649,6 @@ exports[`regression tests > given selected element A with lower z-index than uns
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -7907,7 +7884,6 @@ exports[`regression tests > given selected element A with lower z-index than uns
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -8146,7 +8122,6 @@ exports[`regression tests > key 2 selects rectangle tool > [end of test] appStat
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -8327,7 +8302,6 @@ exports[`regression tests > key 3 selects diamond tool > [end of test] appState
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -8508,7 +8482,6 @@ exports[`regression tests > key 4 selects ellipse tool > [end of test] appState
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -9151,7 +9124,6 @@ exports[`regression tests > key 7 selects freedraw tool > [end of test] appState
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -9579,7 +9551,6 @@ exports[`regression tests > key d selects diamond tool > [end of test] appState
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -9991,7 +9962,6 @@ exports[`regression tests > key o selects ellipse tool > [end of test] appState
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -10170,7 +10140,6 @@ exports[`regression tests > key p selects freedraw tool > [end of test] appState
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -10365,7 +10334,6 @@ exports[`regression tests > key r selects rectangle tool > [end of test] appStat
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -10554,7 +10522,6 @@ exports[`regression tests > make a group and duplicate it > [end of test] appSta
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -11080,7 +11047,6 @@ exports[`regression tests > noop interaction after undo shouldn't create history
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -11357,7 +11323,6 @@ exports[`regression tests > pinch-to-zoom works > [end of test] appState 1`] = `
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -11483,7 +11448,6 @@ exports[`regression tests > shift click on selected element should deselect it o
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -11688,7 +11652,6 @@ exports[`regression tests > shift-click to multiselect, then drag > [end of test
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -12010,7 +11973,6 @@ exports[`regression tests > should group elements and ungroup them > [end of tes
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -12444,7 +12406,6 @@ exports[`regression tests > single-clicking on a subgroup of a selected group sh
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -13076,7 +13037,6 @@ exports[`regression tests > spacebar + drag scrolls the canvas > [end of test] a
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -13204,7 +13164,6 @@ exports[`regression tests > supports nested groups > [end of test] appState 1`]
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -13865,7 +13824,6 @@ exports[`regression tests > switches from group of selected elements to another
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -14204,7 +14162,6 @@ exports[`regression tests > switches selected element on pointer down > [end of
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -14437,7 +14394,6 @@ exports[`regression tests > two-finger scroll works > [end of test] appState 1`]
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -14926,7 +14882,6 @@ exports[`regression tests > updates fontSize & fontFamily appState > [end of tes
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,
@@ -15053,7 +15008,6 @@ exports[`regression tests > zoom hotkeys > [end of test] appState 1`] = `
   "showHyperlinkPopup": false,
   "showWelcomeScreen": true,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,

packages/excalidraw/tests/selection.test.tsx

@@ -615,6 +615,32 @@ describe("box-selection overlap mode", () => {
 
     assertSelectedElements([]);
   });
+
+  it("should not select a framed element when selection only overlaps its clipped-out outline", () => {
+    const frame = API.createElement({
+      type: "frame",
+      x: 100,
+      y: 100,
+      width: 100,
+      height: 100,
+    });
+    const rect1 = API.createElement({
+      type: "rectangle",
+      x: 50,
+      y: 50,
+      width: 200,
+      height: 200,
+      frameId: frame.id,
+      backgroundColor: "red",
+      fillStyle: "solid",
+    });
+
+    API.setElements([frame, rect1]);
+
+    boxSelect(40, 170, 70, 220);
+
+    assertSelectedElements([]);
+  });
 });
 
 describe("inner box-selection", () => {

packages/excalidraw/tests/snapping.test.ts

@@ -0,0 +1,833 @@
+import { arrayToMap } from "@excalidraw/common";
+import {
+  pointFrom,
+  rangeInclusive,
+  type GlobalPoint,
+  type Radians,
+} from "@excalidraw/math";
+
+import type { ExcalidrawElement } from "@excalidraw/element/types";
+
+import { getDefaultAppState } from "../appState";
+import {
+  getElementsCorners,
+  getVisibleGaps,
+  getReferenceSnapPoints,
+  SnapCache,
+  snapDraggedElements,
+} from "../snapping";
+
+import { API } from "./helpers/api";
+
+import type {
+  AppClassProperties,
+  AppState,
+  NormalizedZoomValue,
+} from "../types";
+
+type ReferenceSnapPoints = NonNullable<
+  ReturnType<typeof SnapCache.getReferenceSnapPoints>
+>;
+
+const NO_MODIFIER_KEYS = {
+  altKey: false,
+  ctrlKey: false,
+  metaKey: false,
+  shiftKey: false,
+};
+
+const createSnappingApp = (appState: Partial<AppState> = {}) =>
+  ({
+    props: {},
+    state: {
+      ...getDefaultAppState(),
+      objectsSnapModeEnabled: true,
+      width: 1000,
+      height: 1000,
+      offsetLeft: 0,
+      offsetTop: 0,
+      ...appState,
+    },
+  } as AppClassProperties);
+
+const getHorizontalPointSnapLineCoordinates = (
+  snapLines: ReturnType<typeof snapDraggedElements>["snapLines"],
+) => {
+  return snapLines
+    .filter((snapLine) => snapLine.type === "points")
+    .filter((snapLine) => {
+      const [firstPoint, lastPoint] = snapLine.points;
+
+      return firstPoint[1] === lastPoint[1];
+    })
+    .map((snapLine) => {
+      return snapLine.points[0][1];
+    })
+    .sort((a, b) => a - b);
+};
+
+const getVerticalPointSnapLineCoordinates = (
+  snapLines: ReturnType<typeof snapDraggedElements>["snapLines"],
+) => {
+  return snapLines
+    .filter((snapLine) => snapLine.type === "points")
+    .filter((snapLine) => {
+      const [firstPoint, lastPoint] = snapLine.points;
+
+      return firstPoint[0] === lastPoint[0];
+    })
+    .map((snapLine) => {
+      return snapLine.points[0][0];
+    })
+    .sort((a, b) => a - b);
+};
+
+const getHorizontalPointSnapLineMaxX = (
+  snapLines: ReturnType<typeof snapDraggedElements>["snapLines"],
+) => {
+  const horizontalSnapLine = snapLines
+    .filter((snapLine) => snapLine.type === "points")
+    .find((snapLine) => {
+      const [firstPoint, lastPoint] = snapLine.points;
+
+      return firstPoint[1] === lastPoint[1];
+    });
+
+  if (!horizontalSnapLine) {
+    return null;
+  }
+
+  return horizontalSnapLine.points[horizontalSnapLine.points.length - 1][0];
+};
+
+const getHorizontalPointSnapLineXRange = (
+  snapLines: ReturnType<typeof snapDraggedElements>["snapLines"],
+) => {
+  const horizontalSnapLine = snapLines
+    .filter((snapLine) => snapLine.type === "points")
+    .find((snapLine) => {
+      const [firstPoint, lastPoint] = snapLine.points;
+
+      return firstPoint[1] === lastPoint[1];
+    });
+
+  if (!horizontalSnapLine) {
+    return null;
+  }
+
+  return [
+    horizontalSnapLine.points[0][0],
+    horizontalSnapLine.points[horizontalSnapLine.points.length - 1][0],
+  ] as const;
+};
+
+const getHorizontalGapSnapLines = (
+  snapLines: ReturnType<typeof snapDraggedElements>["snapLines"],
+) => {
+  return snapLines.filter(
+    (snapLine) =>
+      snapLine.type === "gap" && snapLine.direction === "horizontal",
+  );
+};
+
+const getVerticalGapSnapLines = (
+  snapLines: ReturnType<typeof snapDraggedElements>["snapLines"],
+) => {
+  return snapLines.filter(
+    (snapLine) => snapLine.type === "gap" && snapLine.direction === "vertical",
+  );
+};
+
+const getPointKeys = (points: ReturnType<typeof getElementsCorners>) => {
+  return points.map((point) => point.join(","));
+};
+
+const getReferenceSnapPointKeys = (
+  elements: ExcalidrawElement[],
+  selectedElements: ExcalidrawElement[],
+  app: AppClassProperties,
+) => {
+  return new Set(
+    getReferenceSnapPoints(
+      elements,
+      selectedElements,
+      app.state,
+      arrayToMap(elements),
+    ).map((snapPoint) => snapPoint.point.join(",")),
+  );
+};
+
+const primeReferenceSnapPoints = (
+  elements: ExcalidrawElement[],
+  selectedElements: ExcalidrawElement[],
+) => {
+  const selectedElementIds = new Set(
+    selectedElements.map((element) => element.id),
+  );
+  const elementsMap = arrayToMap(elements);
+
+  SnapCache.setReferenceSnapPoints(
+    elements
+      .filter((element) => !selectedElementIds.has(element.id))
+      .flatMap((element) => {
+        const corners = getElementsCorners([element], elementsMap);
+
+        return corners.map((point, index) => ({
+          point,
+          type: index === corners.length - 1 ? "center" : "outer",
+          snapSourceId: element.id,
+        }));
+      }) as Parameters<typeof SnapCache.setReferenceSnapPoints>[0],
+  );
+};
+
+describe("snapping", () => {
+  afterEach(() => {
+    SnapCache.destroy();
+  });
+
+  it("does not use frame children as references when snapping outside elements", () => {
+    const frame = API.createElement({
+      type: "frame",
+      id: "frame",
+      x: 0,
+      y: 0,
+      width: 300,
+      height: 300,
+    });
+    const frameChild = API.createElement({
+      type: "rectangle",
+      id: "frameChild",
+      x: 37,
+      y: 53,
+      width: 71,
+      height: 83,
+      frameId: frame.id,
+    });
+    const selected = API.createElement({
+      type: "rectangle",
+      id: "selected",
+      x: 400,
+      y: 50,
+      width: 100,
+      height: 100,
+    });
+    const elements = [frame, frameChild, selected];
+    const app = createSnappingApp({
+      selectedElementIds: { [selected.id]: true },
+    });
+
+    const referenceSnapPointKeys = getReferenceSnapPointKeys(
+      elements,
+      [selected],
+      app,
+    );
+    const frameChildPointKeys = getPointKeys(
+      getElementsCorners([frameChild], arrayToMap(elements)),
+    );
+
+    expect(
+      frameChildPointKeys.some((pointKey) =>
+        referenceSnapPointKeys.has(pointKey),
+      ),
+    ).toBe(false);
+  });
+
+  it("uses frame siblings as references when snapping elements in the same frame", () => {
+    const frame = API.createElement({
+      type: "frame",
+      id: "frame",
+      x: 0,
+      y: 0,
+      width: 300,
+      height: 300,
+    });
+    const sibling = API.createElement({
+      type: "rectangle",
+      id: "sibling",
+      x: 37,
+      y: 53,
+      width: 71,
+      height: 83,
+      frameId: frame.id,
+    });
+    const selected = API.createElement({
+      type: "rectangle",
+      id: "selected",
+      x: 150,
+      y: 50,
+      width: 100,
+      height: 100,
+      frameId: frame.id,
+    });
+    const elements = [frame, sibling, selected];
+    const app = createSnappingApp({
+      selectedElementIds: { [selected.id]: true },
+    });
+
+    const referenceSnapPointKeys = getReferenceSnapPointKeys(
+      elements,
+      [selected],
+      app,
+    );
+    const siblingPointKeys = getPointKeys(
+      getElementsCorners([sibling], arrayToMap(elements)),
+    );
+
+    expect(
+      siblingPointKeys.some((pointKey) => referenceSnapPointKeys.has(pointKey)),
+    ).toBe(true);
+  });
+
+  it("does not use frame children as references when snapping the frame itself", () => {
+    const frame = API.createElement({
+      type: "frame",
+      id: "frame",
+      x: 0,
+      y: 0,
+      width: 300,
+      height: 300,
+    });
+    const frameChild = API.createElement({
+      type: "rectangle",
+      id: "frameChild",
+      x: 37,
+      y: 53,
+      width: 71,
+      height: 83,
+      frameId: frame.id,
+    });
+    const elements = [frame, frameChild];
+    const app = createSnappingApp({
+      selectedElementIds: { [frame.id]: true },
+    });
+
+    const referenceSnapPointKeys = getReferenceSnapPointKeys(
+      elements,
+      [frame],
+      app,
+    );
+    const frameChildPointKeys = getPointKeys(
+      getElementsCorners([frameChild], arrayToMap(elements)),
+    );
+
+    expect(
+      frameChildPointKeys.some((pointKey) =>
+        referenceSnapPointKeys.has(pointKey),
+      ),
+    ).toBe(false);
+  });
+
+  it("does not use frame children as visible gap references when snapping outside elements", () => {
+    const frame = API.createElement({
+      type: "frame",
+      id: "frame",
+      x: 0,
+      y: 0,
+      width: 500,
+      height: 300,
+    });
+    const frameChildA = API.createElement({
+      type: "rectangle",
+      id: "frameChildA",
+      x: 50,
+      y: 50,
+      width: 100,
+      height: 100,
+      frameId: frame.id,
+    });
+    const frameChildB = API.createElement({
+      type: "rectangle",
+      id: "frameChildB",
+      x: 250,
+      y: 50,
+      width: 100,
+      height: 100,
+      frameId: frame.id,
+    });
+    const selected = API.createElement({
+      type: "rectangle",
+      id: "selected",
+      x: 700,
+      y: 50,
+      width: 100,
+      height: 100,
+    });
+    const elements = [frame, frameChildA, frameChildB, selected];
+    const app = createSnappingApp({
+      selectedElementIds: { [selected.id]: true },
+    });
+
+    const visibleGaps = getVisibleGaps(
+      elements,
+      [selected],
+      app.state,
+      arrayToMap(elements),
+    );
+
+    expect(visibleGaps.horizontalGaps).toHaveLength(0);
+    expect(visibleGaps.verticalGaps).toHaveLength(0);
+  });
+
+  it("filters center and inner outer point snaplines for the same reference", () => {
+    const angle = 0.68 as Radians;
+    const reference = API.createElement({
+      type: "rectangle",
+      id: "reference",
+      x: 0,
+      y: 0,
+      width: 140,
+      height: 140,
+      angle,
+    });
+    const selected = API.createElement({
+      type: "rectangle",
+      id: "selected",
+      x: 200,
+      y: 0,
+      width: 140,
+      height: 140,
+      angle,
+    });
+    const elements = [reference, selected];
+    const app = createSnappingApp({
+      selectedElementIds: { [selected.id]: true },
+    });
+
+    primeReferenceSnapPoints(elements, [selected]);
+
+    const { snapLines } = snapDraggedElements(
+      elements,
+      { x: 0, y: 0 },
+      app,
+      NO_MODIFIER_KEYS,
+      arrayToMap(elements),
+    );
+
+    expect(getHorizontalPointSnapLineCoordinates(snapLines)).toHaveLength(2);
+  });
+
+  it("keeps a snapline that is redundant for one reference but needed for another", () => {
+    const angle = 0.68 as Radians;
+    const selected = API.createElement({
+      type: "rectangle",
+      id: "selected",
+      x: 200,
+      y: 0,
+      width: 140,
+      height: 140,
+      angle,
+    });
+    const elements = [selected];
+    const elementsMap = arrayToMap(elements);
+    const selectedSnapPoints = getElementsCorners([selected], elementsMap);
+    const outerSnapPoints = selectedSnapPoints.slice(0, -1);
+    const centerSnapPoint = selectedSnapPoints[selectedSnapPoints.length - 1];
+    const innerOuterSnapPoint = [...outerSnapPoints].sort(
+      (a, b) => a[1] - b[1],
+    )[1];
+    const app = createSnappingApp({
+      selectedElementIds: { [selected.id]: true },
+    });
+
+    const referenceSnapPoints: ReferenceSnapPoints = [
+      ...outerSnapPoints.map((point) => ({
+        point: pointFrom<GlobalPoint>(point[0] - 200, point[1]),
+        type: "outer" as const,
+        snapSourceId: "referenceA",
+      })),
+      {
+        point: pointFrom<GlobalPoint>(
+          centerSnapPoint[0] - 200,
+          centerSnapPoint[1],
+        ),
+        type: "center" as const,
+        snapSourceId: "referenceA",
+      },
+      {
+        point: pointFrom<GlobalPoint>(
+          innerOuterSnapPoint[0] - 300,
+          innerOuterSnapPoint[1],
+        ),
+        type: "outer" as const,
+        snapSourceId: "referenceB",
+      },
+    ];
+
+    SnapCache.setReferenceSnapPoints(referenceSnapPoints);
+
+    const { snapLines } = snapDraggedElements(
+      elements,
+      { x: 0, y: 0 },
+      app,
+      NO_MODIFIER_KEYS,
+      elementsMap,
+    );
+
+    expect(getHorizontalPointSnapLineCoordinates(snapLines)).toHaveLength(3);
+  });
+
+  it("keeps a center snapline when no outer snaplines imply it", () => {
+    const reference = API.createElement({
+      type: "rectangle",
+      id: "reference",
+      x: 0,
+      y: 0,
+      width: 100,
+      height: 100,
+    });
+    const selected = API.createElement({
+      type: "rectangle",
+      id: "selected",
+      x: 200,
+      y: 25,
+      width: 50,
+      height: 50,
+    });
+    const elements = [reference, selected];
+    const app = createSnappingApp({
+      selectedElementIds: { [selected.id]: true },
+    });
+
+    primeReferenceSnapPoints(elements, [selected]);
+
+    const { snapLines } = snapDraggedElements(
+      elements,
+      { x: 0, y: 0 },
+      app,
+      NO_MODIFIER_KEYS,
+      arrayToMap(elements),
+    );
+
+    expect(getHorizontalPointSnapLineCoordinates(snapLines)).toEqual([50]);
+  });
+
+  it("filters center snaplines when matching outer offsets differ by rounding precision", () => {
+    const selected = API.createElement({
+      type: "rectangle",
+      id: "selected",
+      x: 2532.227563984471,
+      y: -1553.9657067952232,
+      width: 140.1015625,
+      height: 140.1015625,
+    });
+    const reference = API.createElement({
+      type: "rectangle",
+      id: "reference",
+      x: 2532.2275640966914,
+      y: -1299.4323092037737,
+      width: 140.1015625,
+      height: 140.1015625,
+    });
+    const elements = [reference, selected];
+    const app = createSnappingApp({
+      selectedElementIds: { [selected.id]: true },
+    });
+
+    primeReferenceSnapPoints(elements, [selected]);
+
+    const { snapLines } = snapDraggedElements(
+      elements,
+      { x: 0, y: 0 },
+      app,
+      NO_MODIFIER_KEYS,
+      arrayToMap(elements),
+    );
+
+    expect(getVerticalPointSnapLineCoordinates(snapLines)).toEqual([
+      2532.227564, 2672.329126,
+    ]);
+  });
+
+  it("keeps outer snaplines stable while dragging a snapped element through rounding-equivalent offsets", () => {
+    const referenceMiddle = API.createElement({
+      type: "rectangle",
+      id: "referenceMiddle",
+      x: 2532.22756398447,
+      y: -1553.9657067952237,
+      width: 140.1015625,
+      height: 140.1015625,
+    });
+    const referenceAbove = API.createElement({
+      type: "rectangle",
+      id: "referenceAbove",
+      x: 2532.2275637826165,
+      y: -1779.7363232531268,
+      width: 140.1015625,
+      height: 140.1015625,
+    });
+    const selected = API.createElement({
+      type: "rectangle",
+      id: "selected",
+      x: 2532.227563096691,
+      y: -1328.1950902037736,
+      width: 140.1015625,
+      height: 140.1015625,
+    });
+    const elements = [referenceAbove, referenceMiddle, selected];
+    const app = createSnappingApp({
+      selectedElementIds: { [selected.id]: true },
+    });
+
+    primeReferenceSnapPoints(elements, [selected]);
+
+    for (const dragOffsetX of [-4, -1, -0.1, 0, 0.1, 1, 4]) {
+      const { snapLines } = snapDraggedElements(
+        elements,
+        { x: dragOffsetX, y: 0 },
+        app,
+        NO_MODIFIER_KEYS,
+        arrayToMap(elements),
+      );
+      const coordinates = getVerticalPointSnapLineCoordinates(snapLines);
+
+      expect(coordinates).toHaveLength(2);
+      expect(coordinates[1] - coordinates[0]).toBeCloseTo(selected.width, 5);
+    }
+  });
+
+  it("keeps same-offset point snaps even across distant references", () => {
+    const selected = API.createElement({
+      type: "rectangle",
+      id: "selected",
+      x: 0,
+      y: 0,
+      width: 100,
+      height: 100,
+    });
+    const elements = [selected];
+    const app = createSnappingApp({
+      selectedElementIds: { [selected.id]: true },
+    });
+
+    SnapCache.setReferenceSnapPoints([
+      {
+        point: pointFrom<GlobalPoint>(220, 50),
+        type: "center",
+        snapSourceId: "near",
+      },
+      {
+        point: pointFrom<GlobalPoint>(900, 50),
+        type: "center",
+        snapSourceId: "far",
+      },
+    ]);
+
+    const { snapLines } = snapDraggedElements(
+      elements,
+      { x: 0, y: 0 },
+      app,
+      NO_MODIFIER_KEYS,
+      arrayToMap(elements),
+    );
+
+    expect(getHorizontalPointSnapLineMaxX(snapLines)).toBe(900);
+  });
+
+  it("prefers a nearby point snap over a slightly better far offset", () => {
+    const selected = API.createElement({
+      type: "rectangle",
+      id: "selected",
+      x: 0,
+      y: 0,
+      width: 100,
+      height: 100,
+    });
+    const elements = [selected];
+    const app = createSnappingApp({
+      selectedElementIds: { [selected.id]: true },
+    });
+
+    SnapCache.setReferenceSnapPoints([
+      {
+        point: pointFrom<GlobalPoint>(220, 54),
+        type: "center",
+        snapSourceId: "near",
+      },
+      {
+        point: pointFrom<GlobalPoint>(900, 50),
+        type: "center",
+        snapSourceId: "far",
+      },
+    ]);
+
+    const { snapOffset, snapLines } = snapDraggedElements(
+      elements,
+      { x: 0, y: 0 },
+      app,
+      NO_MODIFIER_KEYS,
+      arrayToMap(elements),
+    );
+
+    expect(snapOffset.y).toBe(4);
+    expect(getHorizontalPointSnapLineMaxX(snapLines)).toBe(220);
+  });
+
+  it("keeps same-offset point snaps when references form a continuous cluster", () => {
+    const selected = API.createElement({
+      type: "rectangle",
+      id: "selected",
+      x: 0,
+      y: 0,
+      width: 100,
+      height: 100,
+    });
+    const elements = [selected];
+    const app = createSnappingApp({
+      selectedElementIds: { [selected.id]: true },
+    });
+
+    SnapCache.setReferenceSnapPoints([
+      {
+        point: pointFrom<GlobalPoint>(200, 50),
+        type: "center",
+        snapSourceId: "referenceA",
+      },
+      {
+        point: pointFrom<GlobalPoint>(350, 50),
+        type: "center",
+        snapSourceId: "referenceB",
+      },
+      {
+        point: pointFrom<GlobalPoint>(500, 50),
+        type: "center",
+        snapSourceId: "referenceC",
+      },
+    ]);
+
+    const { snapLines } = snapDraggedElements(
+      elements,
+      { x: 0, y: 0 },
+      app,
+      NO_MODIFIER_KEYS,
+      arrayToMap(elements),
+    );
+
+    expect(getHorizontalPointSnapLineMaxX(snapLines)).toBe(500);
+  });
+
+  it("keeps same-source same-offset point snaps across zoom-scaled cluster breaks", () => {
+    const reference = API.createElement({
+      type: "rectangle",
+      id: "reference",
+      x: 0,
+      y: 0,
+      width: 140.1015625,
+      height: 140.1015625,
+    });
+    const selected = API.createElement({
+      type: "rectangle",
+      id: "selected",
+      x: 338.608871112217,
+      y: 0,
+      width: 140.1015625,
+      height: 140.1015625,
+    });
+    const elements = [reference, selected];
+    const app = createSnappingApp({
+      selectedElementIds: { [selected.id]: true },
+      zoom: { value: 1.5 as NormalizedZoomValue },
+    });
+
+    primeReferenceSnapPoints(elements, [selected]);
+
+    const { snapLines } = snapDraggedElements(
+      elements,
+      { x: 0, y: 0 },
+      app,
+      NO_MODIFIER_KEYS,
+      arrayToMap(elements),
+    );
+
+    const range = getHorizontalPointSnapLineXRange(snapLines);
+
+    expect(range).not.toBe(null);
+    expect(range![0]).toBeCloseTo(reference.x, 6);
+    expect(range![1]).toBeCloseTo(selected.x + selected.width, 6);
+  });
+
+  it("renders gap snaplines when rounded bounds touch the reference gap overlap", () => {
+    const selected = API.createElement({
+      type: "rectangle",
+      id: "selected",
+      x: 0,
+      y: 0.0000004,
+      width: 100,
+      height: 100,
+    });
+    const elements = [selected];
+    const app = createSnappingApp({
+      selectedElementIds: { [selected.id]: true },
+    });
+
+    SnapCache.setVisibleGaps({
+      horizontalGaps: [
+        {
+          startBounds: [200, -100, 300, 0],
+          endBounds: [400, -100, 500, 0],
+          startSide: [pointFrom(300, -100), pointFrom(300, 0)],
+          endSide: [pointFrom(400, -100), pointFrom(400, 0)],
+          overlap: rangeInclusive(-100, 0),
+          length: 100,
+        },
+      ],
+      verticalGaps: [],
+    });
+
+    const { snapLines } = snapDraggedElements(
+      elements,
+      { x: 0, y: 0 },
+      app,
+      NO_MODIFIER_KEYS,
+      arrayToMap(elements),
+    );
+
+    expect(getHorizontalGapSnapLines(snapLines)).toHaveLength(2);
+  });
+
+  it("renders gap snaplines when the winning gap offset only differs by rounding precision", () => {
+    const selected = API.createElement({
+      type: "rectangle",
+      id: "selected",
+      x: 0,
+      y: 399.999999,
+      width: 100,
+      height: 100,
+    });
+    const elements = [selected];
+    const app = createSnappingApp({
+      selectedElementIds: { [selected.id]: true },
+    });
+
+    SnapCache.setReferenceSnapPoints([
+      {
+        point: pointFrom<GlobalPoint>(0, 399.999999),
+        type: "outer",
+        snapSourceId: "reference",
+      },
+    ]);
+    SnapCache.setVisibleGaps({
+      horizontalGaps: [],
+      verticalGaps: [
+        {
+          startBounds: [0, 100, 100, 200],
+          endBounds: [0, 250, 100, 350],
+          startSide: [pointFrom(0, 200), pointFrom(100, 200)],
+          endSide: [pointFrom(0, 250), pointFrom(100, 250)],
+          overlap: rangeInclusive(0, 100),
+          length: 50,
+        },
+      ],
+    });
+
+    const { snapLines } = snapDraggedElements(
+      elements,
+      { x: 0, y: 0 },
+      app,
+      NO_MODIFIER_KEYS,
+      arrayToMap(elements),
+    );
+
+    expect(getVerticalGapSnapLines(snapLines)).toHaveLength(2);
+  });
+});

packages/excalidraw/tests/test-utils.ts

@@ -449,28 +449,29 @@ const stripProps = (
   }, {} as Record<string, any>);
 
 export const checkpointHistory = (history: History, name: string) => {
-  const normalizeHistoryEntry = (entry: History["undoStack"][number]) => {
+  expect(
-    const { markers, ...rest } = entry;
+    history.undoStack.map((x) => ({
-
+      ...x,
-    return {
-      ...rest,
-      ...(markers ? { markers } : {}),
       elements: {
-        ...entry.elements,
+        ...x.elements,
-        added: stripProps(entry.elements.added, ["seed", "versionNonce"]),
+        added: stripProps(x.elements.added, ["seed", "versionNonce"]),
-        removed: stripProps(entry.elements.removed, ["seed", "versionNonce"]),
+        removed: stripProps(x.elements.removed, ["seed", "versionNonce"]),
-        updated: stripProps(entry.elements.updated, ["seed", "versionNonce"]),
+        updated: stripProps(x.elements.updated, ["seed", "versionNonce"]),
       },
-    };
+    })),
-  };
+  ).toMatchSnapshot(`[${name}] undo stack`);
 
-  expect(history.undoStack.map(normalizeHistoryEntry)).toMatchSnapshot(
+  expect(
-    `[${name}] undo stack`,
+    history.redoStack.map((x) => ({
-  );
+      ...x,
-
+      elements: {
-  expect(history.redoStack.map(normalizeHistoryEntry)).toMatchSnapshot(
+        ...x.elements,
-    `[${name}] redo stack`,
+        added: stripProps(x.elements.added, ["seed", "versionNonce"]),
-  );
+        removed: stripProps(x.elements.removed, ["seed", "versionNonce"]),
+        updated: stripProps(x.elements.updated, ["seed", "versionNonce"]),
+      },
+    })),
+  ).toMatchSnapshot(`[${name}] redo stack`);
 };
 
 /**

packages/excalidraw/transaction/diff.ts

@@ -1,289 +0,0 @@
-import { type StoreDelta } from "@excalidraw/element";
-
-import type { Delta } from "@excalidraw/element";
-
-import type { Mutable } from "@excalidraw/common/utility-types";
-import type {
-  ExcalidrawElement,
-  OrderedExcalidrawElement,
-  SceneElementsMap,
-} from "@excalidraw/element/types";
-
-import type {
-  ElementChange,
-  ElementPropName,
-  TouchedElementProps,
-} from "./types";
-
-const LEDGER_IGNORED_PROPS = new Set([
-  "version",
-  "versionNonce",
-  "seed",
-  "updated",
-  "index",
-]);
-
-export const TX_UNDO_OVERRIDE_IGNORED_PROPS = new Set([
-  "version",
-  "versionNonce",
-  "isDeleted",
-]);
-
-type ElementRecord = Record<string, unknown>;
-export type ElementUpdatedProps = Omit<
-  Partial<OrderedExcalidrawElement>,
-  "id" | "updated" | "seed"
->;
-export type ElementUpdatedPropName = Extract<keyof ElementUpdatedProps, string>;
-type ElementPropValueMap = ElementUpdatedProps;
-
-export type ElementUpdatedEntry = Delta<ElementPropValueMap>;
-export type ElementUpdatedEntryMap = Record<string, ElementUpdatedEntry>;
-
-const isPlainObject = (value: unknown): value is Record<string, unknown> =>
-  !!value && typeof value === "object" && !Array.isArray(value);
-
-export const getElementProp = <TProp extends ElementPropName>(
-  element: ExcalidrawElement,
-  prop: TProp,
-): ExcalidrawElement[TProp] =>
-  (element as ElementRecord)[prop] as ExcalidrawElement[TProp];
-
-export const setOrderedElementProp = <TProp extends ElementPropName>(
-  element: Mutable<OrderedExcalidrawElement>,
-  prop: TProp,
-  value: OrderedExcalidrawElement[TProp],
-) => {
-  (element as ElementRecord)[prop] = value;
-};
-
-/** Deep equality used by ledger conflict/touched-prop detection. */
-export const isLedgerValueEqual = (left: unknown, right: unknown): boolean => {
-  if (Object.is(left, right)) {
-    return true;
-  }
-
-  if (Array.isArray(left) && Array.isArray(right)) {
-    if (left.length !== right.length) {
-      return false;
-    }
-    for (let index = 0; index < left.length; index += 1) {
-      if (!isLedgerValueEqual(left[index], right[index])) {
-        return false;
-      }
-    }
-    return true;
-  }
-
-  if (isPlainObject(left) && isPlainObject(right)) {
-    const leftKeys = Object.keys(left);
-    const rightKeys = Object.keys(right);
-    if (leftKeys.length !== rightKeys.length) {
-      return false;
-    }
-    for (const key of leftKeys) {
-      if (!Object.prototype.hasOwnProperty.call(right, key)) {
-        return false;
-      }
-      if (!isLedgerValueEqual(left[key], right[key])) {
-        return false;
-      }
-    }
-    return true;
-  }
-
-  return false;
-};
-
-/** Shallow-copies a scene map. Entries share references with the original. */
-export const shallowCopySceneElements = (
-  elements: ReadonlyMap<string, ExcalidrawElement>,
-): SceneElementsMap => new Map(elements) as SceneElementsMap;
-
-export const createAllTouchedElementProps = (): TouchedElementProps => ({
-  kind: "all",
-});
-
-export const createPartialTouchedElementProps = (
-  props: Iterable<ElementPropName> = [],
-): TouchedElementProps => ({
-  kind: "partial",
-  props: new Set(props),
-});
-
-export const hasTouchedProps = (touchedProps: TouchedElementProps): boolean =>
-  touchedProps.kind === "all" || touchedProps.props.size > 0;
-
-export const touchesWholeElement = (
-  touchedProps: TouchedElementProps,
-): boolean => touchedProps.kind === "all";
-
-export const isPartialTouchedProps = (
-  touchedProps: TouchedElementProps,
-): touchedProps is Extract<TouchedElementProps, { kind: "partial" }> =>
-  touchedProps.kind === "partial";
-
-export const hasTouchedProp = (
-  touchedProps: TouchedElementProps,
-  prop: ElementPropName,
-): boolean => touchedProps.kind === "all" || touchedProps.props.has(prop);
-
-export const mergeTouchedProps = (
-  left: TouchedElementProps,
-  right: TouchedElementProps,
-): TouchedElementProps => {
-  if (left.kind === "all" || right.kind === "all") {
-    return createAllTouchedElementProps();
-  }
-
-  return createPartialTouchedElementProps([...left.props, ...right.props]);
-};
-
-/** Returns changed property names between two element snapshots. */
-export const collectTouchedProps = (
-  before: ExcalidrawElement | null,
-  after: ExcalidrawElement | null,
-): TouchedElementProps => {
-  if (!before || !after) {
-    return createAllTouchedElementProps();
-  }
-
-  const touchedProps = new Set<ElementPropName>();
-  const keys = new Set<ElementPropName>([
-    ...(Object.keys(before) as ElementPropName[]),
-    ...(Object.keys(after) as ElementPropName[]),
-  ]);
-
-  for (const key of keys) {
-    if (LEDGER_IGNORED_PROPS.has(key)) {
-      continue;
-    }
-    if (
-      !isLedgerValueEqual(
-        getElementProp(before, key),
-        getElementProp(after, key),
-      )
-    ) {
-      touchedProps.add(key);
-    }
-  }
-
-  return createPartialTouchedElementProps(touchedProps);
-};
-
-/** Returns ids whose element snapshot changed between two points in time. */
-export const collectChangedElementIds = (
-  before: ReadonlyMap<string, ExcalidrawElement>,
-  after: ReadonlyMap<string, ExcalidrawElement>,
-) => collectElementChanges(before, after).map((change) => change.id);
-
-export const collectElementChanges = (
-  before: ReadonlyMap<string, ExcalidrawElement>,
-  after: ReadonlyMap<string, ExcalidrawElement>,
-): ElementChange[] => {
-  const changes: ElementChange[] = [];
-  const candidateIds = new Set<string>([...before.keys(), ...after.keys()]);
-
-  for (const id of candidateIds) {
-    const beforeElement = before.get(id) ?? null;
-    const afterElement = after.get(id) ?? null;
-    const touchedProps = collectTouchedProps(beforeElement, afterElement);
-    if (!hasTouchedProps(touchedProps)) {
-      continue;
-    }
-
-    changes.push({
-      id,
-      before: beforeElement,
-      after: afterElement,
-      touchedProps,
-    });
-  }
-
-  return changes;
-};
-
-export const serializeConsumedPropKey = (
-  elementId: string,
-  prop: ElementPropName,
-) => `${elementId}\u0000${prop}`;
-
-export const getUpdatedElementEntries = (delta: StoreDelta) =>
-  delta.elements.updated as ElementUpdatedEntryMap;
-
-export const getElementPropEntries = (props: ElementPropValueMap) =>
-  Object.entries(props) as [
-    ElementUpdatedPropName,
-    ElementUpdatedProps[ElementUpdatedPropName],
-  ][];
-
-export const hasUpdatedElementEntries = (delta: StoreDelta) =>
-  Object.keys(getUpdatedElementEntries(delta)).length > 0;
-
-export const serializeIntermediateValue = (value: unknown): string => {
-  const serialize = (input: unknown, seen: WeakSet<object>): string => {
-    if (input === null) {
-      return "null";
-    }
-
-    switch (typeof input) {
-      case "undefined":
-        return "undefined";
-      case "boolean":
-        return input ? "boolean:true" : "boolean:false";
-      case "number":
-        if (Number.isNaN(input)) {
-          return "number:NaN";
-        }
-        if (Object.is(input, -0)) {
-          return "number:-0";
-        }
-        return `number:${input}`;
-      case "bigint":
-        return `bigint:${input.toString()}`;
-      case "string":
-        return `string:${JSON.stringify(input)}`;
-      case "symbol":
-        return `symbol:${String(input)}`;
-      case "function":
-        return `function:${input.name}`;
-      case "object":
-        break;
-      default:
-        return `unknown:${String(input)}`;
-    }
-
-    if (Array.isArray(input)) {
-      if (seen.has(input)) {
-        return "[CircularArray]";
-      }
-      seen.add(input);
-      const serialized = `[${input
-        .map((item) => serialize(item, seen))
-        .join(",")}]`;
-      seen.delete(input);
-      return serialized;
-    }
-
-    if (isPlainObject(input)) {
-      if (seen.has(input)) {
-        return "{CircularObject}";
-      }
-      seen.add(input);
-      const serialized = `{${Object.keys(input)
-        .sort()
-        .map((key) => `${JSON.stringify(key)}:${serialize(input[key], seen)}`)
-        .join(",")}}`;
-      seen.delete(input);
-      return serialized;
-    }
-
-    try {
-      return `object:${JSON.stringify(input)}`;
-    } catch {
-      return `object:${Object.prototype.toString.call(input)}`;
-    }
-  };
-
-  return serialize(value, new WeakSet<object>());
-};

packages/excalidraw/transaction/index.ts

@@ -1,13 +0,0 @@
-export { collectChangedElementIds } from "./diff";
-export { TransactionLedger } from "./ledger";
-export { Transaction } from "./transaction";
-export { TransactionManager } from "./manager";
-
-export type {
-  AppStateResolver,
-  AppStateResolverContext,
-  TransactionElementUpdate,
-  TransactionLedgerEntry,
-  TransactionStatus,
-  TransactionSummary,
-} from "./types";

packages/excalidraw/transaction/ledger.ts

@@ -1,333 +0,0 @@
-import { deepCopyElement } from "@excalidraw/element";
-
-import type { Mutable } from "@excalidraw/common/utility-types";
-import type {
-  ExcalidrawElement,
-  OrderedExcalidrawElement,
-  SceneElementsMap,
-} from "@excalidraw/element/types";
-
-import {
-  collectElementChanges,
-  collectTouchedProps,
-  getElementProp,
-  hasTouchedProps,
-  isLedgerValueEqual,
-  mergeTouchedProps,
-  setOrderedElementProp,
-  shallowCopySceneElements,
-  touchesWholeElement,
-} from "./diff";
-
-import type { TransactionLedgerEntry } from "./types";
-
-/**
- * Keeps transaction-level scene mutations and materializes synthetic snapshots
- * for a single durable history commit.
- */
-export class TransactionLedger {
-  private readonly entries = new Map<string, TransactionLedgerEntry>();
-
-  /** Whether the transaction has any net element mutations. */
-  hasEntries() {
-    return this.entries.size > 0;
-  }
-
-  /** Returns the ledger entry for an element, if any. */
-  getEntry(elementId: string): TransactionLedgerEntry | undefined {
-    return this.entries.get(elementId);
-  }
-
-  /** Releases all ledger entries. */
-  clear() {
-    this.entries.clear();
-  }
-
-  /** Records one element mutation step into the ledger. */
-  recordStep(
-    before: ReadonlyMap<string, ExcalidrawElement>,
-    after: ReadonlyMap<string, ExcalidrawElement>,
-  ) {
-    for (const change of collectElementChanges(before, after)) {
-      const {
-        id: elementId,
-        before: beforeElement,
-        after: afterElement,
-        touchedProps,
-      } = change;
-
-      const existing = this.entries.get(elementId);
-      if (!existing) {
-        this.entries.set(elementId, {
-          baselineElement: beforeElement
-            ? deepCopyElement(beforeElement)
-            : null,
-          targetElement: afterElement ? deepCopyElement(afterElement) : null,
-          touchedProps,
-        });
-        continue;
-      }
-
-      existing.targetElement = afterElement
-        ? deepCopyElement(afterElement)
-        : null;
-      existing.touchedProps = mergeTouchedProps(
-        existing.touchedProps,
-        touchedProps,
-      );
-
-      // Created then deleted inside one transaction leaves no durable footprint.
-      if (!existing.baselineElement && !existing.targetElement) {
-        this.entries.delete(elementId);
-        continue;
-      }
-      if (!existing.baselineElement && existing.targetElement?.isDeleted) {
-        this.entries.delete(elementId);
-      }
-    }
-  }
-
-  /**
-   * Builds synthetic element before/after snapshots with a fixed
-   * "live-wins-per-prop" strategy.
-   */
-  buildSyntheticSnapshots(live: ReadonlyMap<string, ExcalidrawElement>) {
-    // Shallow copy — untouched elements stay as live references.
-    // Only elements mutated in-place (prop-level updates) are deep-copied below.
-    const elementsBefore = shallowCopySceneElements(live);
-    const elementsAfter = shallowCopySceneElements(live);
-
-    for (const [elementId, entry] of this.entries) {
-      this.reconcileEntrySnapshots(
-        elementId,
-        entry,
-        live,
-        elementsBefore,
-        elementsAfter,
-      );
-    }
-
-    return { elementsBefore, elementsAfter };
-  }
-
-  private reconcileEntrySnapshots(
-    elementId: string,
-    entry: TransactionLedgerEntry,
-    live: ReadonlyMap<string, ExcalidrawElement>,
-    elementsBefore: SceneElementsMap,
-    elementsAfter: SceneElementsMap,
-  ) {
-    if (!entry.baselineElement) {
-      this.applyCreatedElementSnapshots(
-        elementId,
-        entry.targetElement,
-        live,
-        elementsBefore,
-        elementsAfter,
-      );
-      return;
-    }
-
-    if (!entry.targetElement) {
-      this.applyDeletedElementSnapshots(
-        elementId,
-        entry.baselineElement,
-        live,
-        elementsBefore,
-        elementsAfter,
-      );
-      return;
-    }
-
-    this.applyUpdatedElementSnapshots(
-      elementId,
-      entry,
-      live,
-      elementsBefore,
-      elementsAfter,
-    );
-  }
-
-  private applyCreatedElementSnapshots(
-    elementId: string,
-    targetElement: ExcalidrawElement | null,
-    live: ReadonlyMap<string, ExcalidrawElement>,
-    elementsBefore: SceneElementsMap,
-    elementsAfter: SceneElementsMap,
-  ) {
-    if (!targetElement) {
-      return;
-    }
-
-    const liveElement = live.get(elementId) ?? null;
-    if (
-      !liveElement ||
-      liveElement.isDeleted ||
-      hasTouchedProps(collectTouchedProps(targetElement, liveElement))
-    ) {
-      return;
-    }
-
-    elementsBefore.delete(elementId);
-    elementsAfter.set(
-      elementId,
-      deepCopyElement(targetElement) as OrderedExcalidrawElement,
-    );
-  }
-
-  private applyDeletedElementSnapshots(
-    elementId: string,
-    baselineElement: ExcalidrawElement,
-    live: ReadonlyMap<string, ExcalidrawElement>,
-    elementsBefore: SceneElementsMap,
-    elementsAfter: SceneElementsMap,
-  ) {
-    const liveElement = live.get(elementId) ?? null;
-    if (liveElement && !liveElement.isDeleted) {
-      return;
-    }
-
-    elementsBefore.set(
-      elementId,
-      deepCopyElement(baselineElement) as OrderedExcalidrawElement,
-    );
-    elementsAfter.delete(elementId);
-  }
-
-  private applyUpdatedElementSnapshots(
-    elementId: string,
-    entry: TransactionLedgerEntry,
-    live: ReadonlyMap<string, ExcalidrawElement>,
-    elementsBefore: SceneElementsMap,
-    elementsAfter: SceneElementsMap,
-  ) {
-    const liveElement = live.get(elementId) ?? null;
-    const targetElement = entry.targetElement;
-    const baselineElement = entry.baselineElement;
-    const beforeElement = elementsBefore.get(elementId);
-    const afterElement = elementsAfter.get(elementId);
-
-    if (
-      !liveElement ||
-      !baselineElement ||
-      !targetElement ||
-      !beforeElement ||
-      !afterElement
-    ) {
-      return;
-    }
-
-    if (touchesWholeElement(entry.touchedProps)) {
-      this.applyWholeElementSnapshots(
-        elementId,
-        baselineElement,
-        targetElement,
-        liveElement,
-        elementsBefore,
-        elementsAfter,
-      );
-      return;
-    }
-
-    this.applyPerPropSnapshots({
-      entry,
-      liveElement,
-      baselineElement,
-      targetElement,
-      beforeElement,
-      afterElement,
-      elementId,
-      elementsBefore,
-      elementsAfter,
-    });
-  }
-
-  private applyWholeElementSnapshots(
-    elementId: string,
-    baselineElement: ExcalidrawElement,
-    targetElement: ExcalidrawElement,
-    liveElement: ExcalidrawElement,
-    elementsBefore: SceneElementsMap,
-    elementsAfter: SceneElementsMap,
-  ) {
-    const hasLiveConflict = hasTouchedProps(
-      collectTouchedProps(targetElement, liveElement),
-    );
-    if (hasLiveConflict) {
-      return;
-    }
-
-    elementsBefore.set(
-      elementId,
-      deepCopyElement(baselineElement) as OrderedExcalidrawElement,
-    );
-    elementsAfter.set(
-      elementId,
-      deepCopyElement(targetElement) as OrderedExcalidrawElement,
-    );
-  }
-
-  private applyPerPropSnapshots(args: {
-    entry: TransactionLedgerEntry;
-    liveElement: ExcalidrawElement;
-    baselineElement: ExcalidrawElement;
-    targetElement: ExcalidrawElement;
-    beforeElement: ExcalidrawElement;
-    afterElement: ExcalidrawElement;
-    elementId: string;
-    elementsBefore: SceneElementsMap;
-    elementsAfter: SceneElementsMap;
-  }) {
-    const {
-      entry,
-      liveElement,
-      baselineElement,
-      targetElement,
-      beforeElement,
-      afterElement,
-      elementId,
-      elementsBefore,
-      elementsAfter,
-    } = args;
-
-    // Deep-copy before mutating so we never touch live elements.
-    const mutableBefore = deepCopyElement(
-      beforeElement,
-    ) as Mutable<OrderedExcalidrawElement>;
-    const mutableAfter = deepCopyElement(
-      afterElement,
-    ) as Mutable<OrderedExcalidrawElement>;
-    elementsBefore.set(elementId, mutableBefore as OrderedExcalidrawElement);
-    elementsAfter.set(elementId, mutableAfter as OrderedExcalidrawElement);
-
-    if (entry.touchedProps.kind !== "partial") {
-      return;
-    }
-
-    let appliedProps = 0;
-    for (const prop of entry.touchedProps.props) {
-      const liveValue = getElementProp(liveElement, prop);
-      const targetValue = getElementProp(targetElement, prop);
-      if (!isLedgerValueEqual(liveValue, targetValue)) {
-        continue;
-      }
-
-      setOrderedElementProp(
-        mutableBefore,
-        prop,
-        getElementProp(baselineElement, prop),
-      );
-      setOrderedElementProp(mutableAfter, prop, targetValue);
-      appliedProps += 1;
-    }
-
-    if (appliedProps === 0) {
-      return;
-    }
-
-    mutableBefore.version = baselineElement.version;
-    mutableBefore.versionNonce = baselineElement.versionNonce;
-    mutableAfter.version = targetElement.version;
-    mutableAfter.versionNonce = targetElement.versionNonce;
-  }
-}

packages/excalidraw/transaction/manager.ts

@@ -1,291 +0,0 @@
-import {
-  Delta,
-  ElementsDelta,
-  mergeStoreDeltaMarkers,
-  type StoreDelta,
-  type TxUndoOverride,
-} from "@excalidraw/element";
-
-import type { Mutable } from "@excalidraw/common/utility-types";
-
-import {
-  HistoryDelta,
-  type HistoryBeforeRecordListener,
-  type HistoryEffectiveDeltaResolverContext,
-} from "../history";
-
-import {
-  type ElementUpdatedPropName,
-  getUpdatedElementEntries,
-  hasUpdatedElementEntries,
-  isLedgerValueEqual,
-  type ElementUpdatedProps,
-  type ElementUpdatedEntryMap,
-} from "./diff";
-import { Transaction } from "./transaction";
-
-import type { AppClassProperties } from "../types";
-import type { TransactionStatus } from "./types";
-
-type TransactionRecord = {
-  tx: Transaction | null;
-  phase: TransactionStatus;
-};
-type TransactionHistoryBridge = {
-  onBeforeRecord: (callback: HistoryBeforeRecordListener) => () => void;
-  setEffectiveDeltaResolver: (
-    resolver:
-      | ((
-          delta: HistoryDelta,
-          context: HistoryEffectiveDeltaResolverContext,
-        ) => HistoryDelta)
-      | null,
-  ) => void;
-};
-
-type MutableElementUpdatedProps = Mutable<ElementUpdatedProps>;
-
-const setElementUpdatedOverride = (
-  overrides: MutableElementUpdatedProps,
-  prop: ElementUpdatedPropName,
-  value: unknown,
-) => {
-  (overrides as Record<ElementUpdatedPropName, unknown>)[prop] = value;
-};
-
-/**
- * Thin factory that holds the app reference and creates Transaction instances.
- */
-export class TransactionManager {
-  private readonly app: AppClassProperties;
-  /**
-   * Single authoritative lifecycle registry for transactions.
-   *
-   * We retain ended/canceled metadata after the tx object is released because
-   * history markers only persist `txId`; undo/redo still needs to resolve
-   * whether a tx was active or already ended when applying effective deltas.
-   */
-  private readonly transactionRecords = new Map<string, TransactionRecord>();
-  /**
-   * Active transaction ids ordered by most-recent registration first.
-   * This preserves deterministic priority when multiple active txs overlap on
-   * the same element+prop and compete to reserve override markers.
-   */
-  private readonly activeTransactionIdsByPriority: string[] = [];
-  private detachBeforeRecordHook: (() => void) | null = null;
-
-  constructor(app: AppClassProperties) {
-    this.app = app;
-  }
-
-  /**
-   * Binds transaction bookkeeping to history lifecycle hooks.
-   * Call once during app initialization.
-   */
-  attachHistory(history: TransactionHistoryBridge) {
-    this.detachBeforeRecordHook?.();
-    history.setEffectiveDeltaResolver((delta, context) =>
-      this.resolveEffectiveDelta(delta, context),
-    );
-    this.detachBeforeRecordHook = history.onBeforeRecord((delta) =>
-      this.onDurableIncrement(delta),
-    );
-  }
-
-  private removeActiveTransactionId(txId: string) {
-    const txIndex = this.activeTransactionIdsByPriority.indexOf(txId);
-    if (txIndex >= 0) {
-      this.activeTransactionIdsByPriority.splice(txIndex, 1);
-    }
-  }
-
-  private getRequiredTransactionRecord(txId: string): TransactionRecord {
-    const record = this.transactionRecords.get(txId);
-    if (!record) {
-      throw new Error(`Unknown transaction: ${txId}`);
-    }
-
-    return record;
-  }
-
-  registerTransaction(tx: Transaction) {
-    this.transactionRecords.set(tx.id, {
-      tx,
-      phase: "active",
-    });
-    this.activeTransactionIdsByPriority.unshift(tx.id);
-  }
-
-  detachTransactionInstance(txId: string) {
-    const record = this.getRequiredTransactionRecord(txId);
-    record.tx = null;
-    this.removeActiveTransactionId(txId);
-  }
-
-  getStatus(txId: string): TransactionStatus {
-    return this.getRequiredTransactionRecord(txId).phase;
-  }
-
-  private markTransactionFinished(
-    txId: string,
-    phase: Exclude<TransactionStatus, "active">,
-  ): TransactionStatus {
-    const record = this.getRequiredTransactionRecord(txId);
-    if (record.phase !== "active") {
-      return record.phase;
-    }
-
-    record.phase = phase;
-    this.removeActiveTransactionId(txId);
-    return record.phase;
-  }
-
-  markTransactionCommitted(txId: string): TransactionStatus {
-    return this.markTransactionFinished(txId, "committed");
-  }
-
-  markTransactionCanceled(txId: string): TransactionStatus {
-    return this.markTransactionFinished(txId, "canceled");
-  }
-
-  onDurableIncrement(delta: StoreDelta) {
-    if (this.activeTransactionIdsByPriority.length === 0) {
-      return;
-    }
-    if (!hasUpdatedElementEntries(delta)) {
-      return;
-    }
-
-    const txUndoOverrides = this.collectUndoOverrides(delta);
-    if (txUndoOverrides.length === 0) {
-      return;
-    }
-
-    mergeStoreDeltaMarkers(delta, { txUndoOverrides });
-  }
-
-  private collectUndoOverrides(delta: StoreDelta): TxUndoOverride[] {
-    const overrides: TxUndoOverride[] = [];
-    const reservedConsumedKeys = new Set<string>();
-
-    for (const txId of this.activeTransactionIdsByPriority) {
-      const record = this.transactionRecords.get(txId);
-      if (!record || record.phase !== "active" || !record.tx) {
-        continue;
-      }
-
-      const txOverrides = record.tx.collectUndoOverridesForDelta(
-        delta,
-        reservedConsumedKeys,
-      );
-
-      for (const override of txOverrides) {
-        if (reservedConsumedKeys.has(override.consumedKey)) {
-          continue;
-        }
-
-        reservedConsumedKeys.add(override.consumedKey);
-        overrides.push(override);
-      }
-    }
-
-    return overrides;
-  }
-
-  private resolveEffectiveDelta(
-    delta: HistoryDelta,
-    _context: HistoryEffectiveDeltaResolverContext,
-  ): HistoryDelta {
-    const txUndoOverrides = delta.markers?.txUndoOverrides;
-    if (!txUndoOverrides || txUndoOverrides.length === 0) {
-      return delta;
-    }
-
-    const updatedEntries = getUpdatedElementEntries(delta);
-    const insertedOverridesByElement = new Map<
-      string,
-      MutableElementUpdatedProps
-    >();
-
-    for (const override of txUndoOverrides) {
-      if (!this.shouldApplyUndoOverride(override.txId)) {
-        continue;
-      }
-
-      const currentEntry = updatedEntries[override.elementId];
-      if (!currentEntry) {
-        continue;
-      }
-
-      const prop = override.prop as ElementUpdatedPropName;
-      const currentInsertedValue = currentEntry.inserted[prop];
-      if (
-        !isLedgerValueEqual(
-          currentInsertedValue,
-          override.expectedInsertedValue,
-        )
-      ) {
-        // Guard against over-applying once the delta has already evolved.
-        continue;
-      }
-
-      const elementOverrides = insertedOverridesByElement.get(
-        override.elementId,
-      );
-      if (elementOverrides) {
-        setElementUpdatedOverride(
-          elementOverrides,
-          prop,
-          override.preTxBaselineValue,
-        );
-      } else {
-        const nextOverrides: MutableElementUpdatedProps = {};
-        setElementUpdatedOverride(
-          nextOverrides,
-          prop,
-          override.preTxBaselineValue,
-        );
-        insertedOverridesByElement.set(override.elementId, nextOverrides);
-      }
-    }
-
-    if (insertedOverridesByElement.size === 0) {
-      return delta;
-    }
-
-    const nextUpdatedEntries: ElementUpdatedEntryMap = {
-      ...updatedEntries,
-    };
-    for (const [elementId, insertedOverrides] of insertedOverridesByElement) {
-      const currentEntry = updatedEntries[elementId];
-      if (!currentEntry) {
-        continue;
-      }
-
-      nextUpdatedEntries[elementId] = Delta.create(
-        { ...currentEntry.deleted },
-        { ...currentEntry.inserted, ...insertedOverrides },
-      );
-    }
-
-    const effectiveElements = ElementsDelta.create(
-      delta.elements.added,
-      delta.elements.removed,
-      nextUpdatedEntries,
-    );
-
-    return HistoryDelta.create(effectiveElements, delta.appState, {
-      id: delta.id,
-      markers: delta.markers,
-    }) as HistoryDelta;
-  }
-
-  private shouldApplyUndoOverride(txId: string): boolean {
-    const record = this.transactionRecords.get(txId);
-    return !!record && record.phase !== "active";
-  }
-
-  create(): Transaction {
-    return new Transaction(this.app, this);
-  }
-}

packages/excalidraw/transaction/transaction.ts

@@ -1,286 +0,0 @@
-import { randomId } from "@excalidraw/common";
-import {
-  CaptureUpdateAction,
-  newElementWith,
-  type ElementUpdate,
-  type StoreDelta,
-  type TxUndoOverride,
-} from "@excalidraw/element";
-
-import { shallowCopySceneElements } from "./diff";
-import { TransactionLedger } from "./ledger";
-
-import {
-  type AppStateResolver,
-  type AppStateResolverContext,
-  type TransactionElementOfType,
-  type TransactionElementUpdate,
-  type TransactionStatus,
-  type TransactionSummary,
-} from "./types";
-import { TxUndoOverridePlanner } from "./undoOverridePlanner";
-
-import type { TransactionManager } from "./manager";
-import type {
-  AppClassProperties,
-  AppState,
-  ObservedAppState,
-  SceneData,
-} from "../types";
-
-type CommitOptions = {
-  resolveAppState?: AppStateResolver;
-};
-
-/**
- * A transaction that records mutations via `updateScene(NEVER)` and commits
- * a single synthetic durable history entry at the end.
- */
-export class Transaction {
-  public readonly id = `tx-${randomId()}`;
-
-  private readonly app: AppClassProperties;
-  private readonly manager: TransactionManager;
-  private readonly ledger = new TransactionLedger();
-  private readonly undoOverridePlanner = new TxUndoOverridePlanner();
-  private readonly initialAppState: Partial<ObservedAppState>;
-
-  private accumulatedAppState: Record<string, unknown> = {};
-  private cachedSummary: TransactionSummary | null = null;
-
-  constructor(app: AppClassProperties, manager: TransactionManager) {
-    this.app = app;
-    this.manager = manager;
-    this.initialAppState = { ...app.store.snapshot.appState };
-    this.manager.registerTransaction(this);
-  }
-
-  get status(): TransactionStatus {
-    return this.manager.getStatus(this.id);
-  }
-
-  private assertActive(action: string): void {
-    const status = this.status;
-    if (status !== "active") {
-      throw new Error(
-        `Cannot ${action} — transaction ${this.id} is already ${status}.`,
-      );
-    }
-  }
-
-  private closeTransaction() {
-    this.manager.detachTransactionInstance(this.id);
-    this.undoOverridePlanner.clear();
-  }
-
-  public collectUndoOverridesForDelta(
-    delta: StoreDelta,
-    reservedConsumedKeys: Set<string>,
-  ): TxUndoOverride[] {
-    if (this.status !== "active") {
-      return [];
-    }
-
-    const candidates =
-      this.undoOverridePlanner.collectCandidatesForDurableDelta(
-        delta,
-        (elementId) => this.ledger.getEntry(elementId),
-        reservedConsumedKeys,
-      );
-
-    if (candidates.length === 0) {
-      return [];
-    }
-
-    const overrides: TxUndoOverride[] = [];
-    for (const candidate of candidates) {
-      this.undoOverridePlanner.markConsumed(candidate.consumedKey);
-      overrides.push({
-        txId: this.id,
-        ...candidate,
-      });
-    }
-
-    return overrides;
-  }
-
-  updateScene<K extends keyof AppState>(data: {
-    elements?: SceneData["elements"];
-    appState?: Pick<AppState, K> | null;
-  }): void {
-    this.assertActive("updateScene");
-
-    // Snapshot before (shallow copy — replaceAllElements mutates the map in-place)
-    const before = shallowCopySceneElements(
-      this.app.scene.getElementsMapIncludingDeleted(),
-    );
-
-    // Apply through the real updateScene with NEVER.
-    this.app.api.updateScene({
-      elements: data.elements,
-      appState: data.appState,
-      captureUpdate: CaptureUpdateAction.NEVER,
-    });
-
-    // Snapshot after
-    const after = this.app.scene.getElementsMapIncludingDeleted();
-
-    this.undoOverridePlanner.recordStep(before, after);
-
-    // Record element diff into ledger
-    this.ledger.recordStep(before, after);
-
-    // Accumulate appState intent
-    if (data.appState) {
-      this.accumulatedAppState = {
-        ...this.accumulatedAppState,
-        ...(data.appState as Record<string, unknown>),
-      };
-    }
-  }
-
-  /**
-   * Partial element updates convenience API.
-   *
-   * Example:
-   * tx.updateElements({
-   *   elements: [
-   *     { id: "a", type: "rectangle", updates: { strokeColor: "#f00" } },
-   *     { id: "b", type: "rectangle", updates: { x: 10, y: 20 } },
-   *   ],
-   * })
-   */
-  updateElements<K extends keyof AppState>(data: {
-    elements: readonly TransactionElementUpdate[];
-    appState?: Pick<AppState, K> | null;
-  }): void {
-    const updatesById = new Map<string, TransactionElementUpdate>();
-
-    for (const update of data.elements) {
-      updatesById.set(update.id, update);
-    }
-
-    if (updatesById.size === 0) {
-      this.updateScene({ appState: data.appState });
-      return;
-    }
-
-    const nextElements = this.app.scene
-      .getElementsIncludingDeleted()
-      .map((element) => {
-        const update = updatesById.get(element.id);
-        if (!update) {
-          return element;
-        }
-        if (element.type !== update.type) {
-          throw new Error(
-            `Cannot apply tx.updateElements update for "${update.id}": expected "${update.type}", got "${element.type}".`,
-          );
-        }
-
-        type MatchingElement = TransactionElementOfType<typeof update.type>;
-        return newElementWith(
-          element as MatchingElement,
-          update.updates as ElementUpdate<MatchingElement>,
-        );
-      });
-
-    this.updateScene({
-      elements: nextElements,
-      appState: data.appState,
-    });
-  }
-
-  commit(options?: CommitOptions): TransactionSummary {
-    if (this.cachedSummary) {
-      return this.cachedSummary;
-    }
-
-    this.manager.markTransactionCommitted(this.id);
-    let historyCommitted = false;
-    try {
-      historyCommitted = this.hasPendingWork()
-        ? this.commitHistoryEntry(options)
-        : false;
-    } finally {
-      this.closeTransaction();
-    }
-
-    const status = this.status;
-    this.cachedSummary = {
-      id: this.id,
-      status,
-      historyCommitted,
-    };
-    this.ledger.clear();
-    return this.cachedSummary;
-  }
-
-  private hasPendingWork() {
-    return this.ledger.hasEntries() || this.hasAccumulatedAppStateIntent();
-  }
-
-  private hasAccumulatedAppStateIntent() {
-    return Object.keys(this.accumulatedAppState).length > 0;
-  }
-
-  private commitHistoryEntry(options?: CommitOptions) {
-    const liveMap = this.app.scene.getElementsMapIncludingDeleted();
-    const { elementsBefore, elementsAfter } =
-      this.ledger.buildSyntheticSnapshots(liveMap);
-
-    const appStateDelta = this.resolveCommitAppStateDelta(options);
-
-    return this.app.store.commitSyntheticIncrement({
-      logicalBefore: { elements: elementsBefore },
-      logicalAfter: {
-        elements: elementsAfter,
-        appState: appStateDelta,
-      },
-    });
-  }
-
-  private resolveCommitAppStateDelta(
-    options?: CommitOptions,
-  ): Partial<ObservedAppState> | undefined {
-    if (!this.hasAccumulatedAppStateIntent()) {
-      return undefined;
-    }
-
-    if (!options?.resolveAppState) {
-      return this.accumulatedAppState as Partial<ObservedAppState>;
-    }
-
-    const context: AppStateResolverContext = {
-      initial: this.initialAppState,
-      accumulated: this.accumulatedAppState as Partial<ObservedAppState>,
-      live: { ...this.app.store.snapshot.appState },
-    };
-    const resolved = options.resolveAppState(context);
-
-    if (!resolved || Object.keys(resolved).length === 0) {
-      return undefined;
-    }
-    return resolved;
-  }
-
-  cancel(): TransactionSummary {
-    if (this.cachedSummary) {
-      return this.cachedSummary;
-    }
-
-    if (this.status === "active") {
-      this.manager.markTransactionCanceled(this.id);
-    }
-
-    this.closeTransaction();
-    const status = this.status;
-    this.cachedSummary = {
-      id: this.id,
-      status,
-      historyCommitted: false,
-    };
-    this.ledger.clear();
-    return this.cachedSummary;
-  }
-}

packages/excalidraw/transaction/types.ts

@@ -1,83 +0,0 @@
-import type { ElementUpdate } from "@excalidraw/element";
-
-import type {
-  ExcalidrawElement,
-  ExcalidrawNonSelectionElement,
-} from "@excalidraw/element/types";
-
-import type { ObservedAppState } from "../types";
-
-export type ElementPropName = Extract<keyof ExcalidrawElement, string>;
-
-export type TouchedElementProps =
-  | { kind: "all" }
-  | { kind: "partial"; props: Set<ElementPropName> };
-
-export type ElementChange = {
-  id: ExcalidrawElement["id"];
-  before: ExcalidrawElement | null;
-  after: ExcalidrawElement | null;
-  touchedProps: TouchedElementProps;
-};
-
-/** Per-element ledger record captured during a transaction session. */
-export type TransactionLedgerEntry = {
-  baselineElement: ExcalidrawElement | null;
-  targetElement: ExcalidrawElement | null;
-  touchedProps: TouchedElementProps;
-};
-
-/** Lifecycle state of a transaction. */
-export type TransactionStatus = "active" | "committed" | "canceled";
-
-/** Per-element partial patch used by tx.updateElements(). */
-export type TransactionUpdatableElementType =
-  ExcalidrawNonSelectionElement["type"];
-
-export type TransactionElementOfType<
-  TType extends TransactionUpdatableElementType,
-> = Extract<ExcalidrawNonSelectionElement, { type: TType }>;
-
-export type TransactionElementUpdate<
-  TType extends TransactionUpdatableElementType = TransactionUpdatableElementType,
-> = TType extends TransactionUpdatableElementType
-  ? {
-      id: ExcalidrawElement["id"];
-      type: TType;
-      updates: ElementUpdate<TransactionElementOfType<TType>>;
-    }
-  : never;
-
-/** Final summary returned when a transaction is committed or canceled. */
-export type TransactionSummary = {
-  id: string;
-  status: TransactionStatus;
-  historyCommitted: boolean;
-};
-
-/** Three-way appState context provided to the resolver at commit time. */
-export type AppStateResolverContext = {
-  /** AppState snapshot captured when the transaction was created. */
-  initial: Partial<ObservedAppState>;
-  /** Merged appState intent from all updateScene calls during the transaction. */
-  accumulated: Partial<ObservedAppState>;
-  /** Current live appState at commit time. */
-  live: Partial<ObservedAppState>;
-};
-
-/**
- * Caller-provided resolver that determines which appState changes are
- * recorded in the history entry.
- *
- * Unlike elements — where per-property conflict detection works because
- * element properties are largely independent — appState keys are often
- * interdependent (e.g. selectedElementIds ↔ selectedGroupIds must stay
- * consistent). The correct merge strategy therefore depends on the
- * caller's semantic context, not on a generic policy.
- *
- * Return the appState delta to record in history, or undefined to skip
- * appState changes entirely.
- */
-export type AppStateResolver = (
-  context: AppStateResolverContext,
-) => Partial<ObservedAppState> | undefined;

packages/excalidraw/transaction/undoOverridePlanner.ts

@@ -1,283 +0,0 @@
-import type { StoreDelta, TxUndoOverride } from "@excalidraw/element";
-
-import type { ExcalidrawElement } from "@excalidraw/element/types";
-
-import {
-  TX_UNDO_OVERRIDE_IGNORED_PROPS,
-  collectElementChanges,
-  getElementProp,
-  getElementPropEntries,
-  getUpdatedElementEntries,
-  hasTouchedProp,
-  isPartialTouchedProps,
-  isLedgerValueEqual,
-  serializeConsumedPropKey,
-  serializeIntermediateValue,
-  touchesWholeElement,
-  type ElementUpdatedEntry,
-} from "./diff";
-
-import type {
-  ElementPropName,
-  TouchedElementProps,
-  TransactionLedgerEntry,
-} from "./types";
-
-type TxUndoOverrideCandidate = Omit<TxUndoOverride, "txId">;
-
-/**
- * Per-element-prop history of tx intermediate values.
- *
- * We keep:
- * - the full sequence for exact deep-equality fallback
- * - a serialized signature set for fast negative lookups
- * - the latest value for the most common positive lookup path
- */
-class TxIntermediateValueHistory {
-  private readonly values: unknown[] = [];
-  private readonly signatures = new Set<string>();
-  private latestValue: unknown;
-  private hasLatestValue = false;
-
-  /** Appends a new intermediate value, skipping consecutive duplicates. */
-  add(value: unknown) {
-    if (this.hasLatestValue && isLedgerValueEqual(this.latestValue, value)) {
-      return;
-    }
-
-    this.values.push(value);
-    this.signatures.add(serializeIntermediateValue(value));
-    this.latestValue = value;
-    this.hasLatestValue = true;
-  }
-
-  /** Returns whether the candidate appeared in this tx prop history. */
-  contains(candidate: unknown) {
-    const candidateSignature = serializeIntermediateValue(candidate);
-    if (!this.signatures.has(candidateSignature)) {
-      return false;
-    }
-
-    if (
-      this.hasLatestValue &&
-      isLedgerValueEqual(this.latestValue, candidate)
-    ) {
-      return true;
-    }
-
-    return this.values.some((value) => isLedgerValueEqual(value, candidate));
-  }
-}
-
-/**
- * Tracks tx intermediate values and computes undo baseline override markers
- * for durable user deltas recorded while tx is active.
- *
- * High-level flow:
- * 1. `recordStep()` observes every in-tx scene mutation and records the
- *    intermediate value reached by each touched element prop.
- * 2. When a durable user delta is about to be recorded,
- *    `collectCandidatesForDurableDelta()` checks whether that delta's
- *    deleted-baseline values match any tx intermediate value.
- * 3. If they do, we emit override candidates so undo can restore the pre-tx
- *    baseline once the tx has ended.
- * 4. `markConsumed()` ensures only the first polluted durable entry for a
- *    given element+prop gets patched; later user actions keep their own
- *    action-local undo baseline.
- */
-export class TxUndoOverridePlanner {
-  private readonly intermediateValuesByElementProp = new Map<
-    string,
-    Map<ElementPropName, TxIntermediateValueHistory>
-  >();
-  private readonly consumedOverridePropKeys = new Set<string>();
-
-  /** Resets planner state when the transaction finishes. */
-  clear() {
-    this.consumedOverridePropKeys.clear();
-    this.intermediateValuesByElementProp.clear();
-  }
-
-  /** Records per-prop intermediate values reached by one in-tx scene step. */
-  recordStep(
-    before: ReadonlyMap<string, ExcalidrawElement>,
-    after: ReadonlyMap<string, ExcalidrawElement>,
-  ) {
-    for (const change of collectElementChanges(before, after)) {
-      const { id: elementId, after: afterElement, touchedProps } = change;
-
-      if (!afterElement || !isPartialTouchedProps(touchedProps)) {
-        continue;
-      }
-
-      for (const prop of touchedProps.props) {
-        this.recordIntermediateValue(
-          elementId,
-          prop,
-          getElementProp(afterElement, prop),
-        );
-      }
-    }
-  }
-
-  /**
-   * Collects override candidates for one durable user delta recorded while the
-   * tx is active.
-   */
-  collectCandidatesForDurableDelta(
-    delta: StoreDelta,
-    getLedgerEntry: (elementId: string) => TransactionLedgerEntry | undefined,
-    reservedConsumedKeys: Set<string>,
-  ): TxUndoOverrideCandidate[] {
-    const candidates: TxUndoOverrideCandidate[] = [];
-
-    for (const [elementId, deltaEntry] of Object.entries(
-      getUpdatedElementEntries(delta),
-    )) {
-      const ledgerEntry = getLedgerEntry(elementId);
-      if (!ledgerEntry) {
-        continue;
-      }
-
-      const elementCandidates = this.collectCandidatesForElement(
-        elementId,
-        deltaEntry,
-        ledgerEntry,
-        reservedConsumedKeys,
-      );
-      if (elementCandidates.length > 0) {
-        candidates.push(...elementCandidates);
-      }
-    }
-
-    return candidates;
-  }
-
-  /** Evaluates one element's updated entry against the tx ledger snapshot. */
-  private collectCandidatesForElement(
-    elementId: string,
-    deltaEntry: ElementUpdatedEntry,
-    ledgerEntry: TransactionLedgerEntry,
-    reservedConsumedKeys: Set<string>,
-  ): TxUndoOverrideCandidate[] {
-    const { baselineElement, touchedProps } = ledgerEntry;
-    if (!baselineElement || touchesWholeElement(touchedProps)) {
-      return [];
-    }
-
-    const candidates: TxUndoOverrideCandidate[] = [];
-    for (const [prop, deletedValue] of getElementPropEntries(
-      deltaEntry.deleted,
-    )) {
-      const candidate = this.createCandidateForProp({
-        elementId,
-        prop,
-        deletedValue,
-        baselineElement,
-        touchedProps,
-        reservedConsumedKeys,
-      });
-      if (candidate) {
-        candidates.push(candidate);
-      }
-    }
-
-    return candidates;
-  }
-
-  /**
-   * Returns an override candidate for one element+prop when the durable delta's
-   * deleted baseline was polluted by a tx intermediate value.
-   */
-  private createCandidateForProp(args: {
-    elementId: string;
-    prop: ElementPropName;
-    deletedValue: unknown;
-    baselineElement: ExcalidrawElement;
-    touchedProps: TouchedElementProps;
-    reservedConsumedKeys: Set<string>;
-  }): TxUndoOverrideCandidate | null {
-    const { elementId, prop, deletedValue, baselineElement, touchedProps } =
-      args;
-
-    if (
-      TX_UNDO_OVERRIDE_IGNORED_PROPS.has(prop) ||
-      !hasTouchedProp(touchedProps, prop)
-    ) {
-      return null;
-    }
-
-    const consumedPropKey = serializeConsumedPropKey(elementId, prop);
-    // Override only the first polluted user entry for this element+prop.
-    // Later user actions should keep action-local undo baselines.
-    if (
-      this.consumedOverridePropKeys.has(consumedPropKey) ||
-      args.reservedConsumedKeys.has(consumedPropKey)
-    ) {
-      return null;
-    }
-
-    if (!this.matchesIntermediateValue(elementId, prop, deletedValue)) {
-      return null;
-    }
-
-    return {
-      elementId,
-      prop,
-      expectedInsertedValue: deletedValue,
-      preTxBaselineValue: getElementProp(baselineElement, prop),
-      consumedKey: consumedPropKey,
-    };
-  }
-
-  /** Marks an element+prop override as consumed by an earlier durable entry. */
-  markConsumed(consumedPropKey: string) {
-    this.consumedOverridePropKeys.add(consumedPropKey);
-  }
-
-  /** Returns the per-prop history map for one element, creating it if needed. */
-  private getOrCreatePropValues(elementId: string) {
-    const existing = this.intermediateValuesByElementProp.get(elementId);
-    if (existing) {
-      return existing;
-    }
-
-    const created = new Map<ElementPropName, TxIntermediateValueHistory>();
-    this.intermediateValuesByElementProp.set(elementId, created);
-    return created;
-  }
-
-  /** Appends one observed intermediate value for an element prop. */
-  private recordIntermediateValue(
-    elementId: string,
-    prop: ElementPropName,
-    value: unknown,
-  ) {
-    const propValues = this.getOrCreatePropValues(elementId);
-    const history = propValues.get(prop);
-    if (history) {
-      history.add(value);
-      return;
-    }
-
-    const nextHistory = new TxIntermediateValueHistory();
-    nextHistory.add(value);
-    propValues.set(prop, nextHistory);
-  }
-
-  /** Checks whether a durable delta baseline matches any tx intermediate value. */
-  private matchesIntermediateValue(
-    elementId: string,
-    prop: ElementPropName,
-    candidate: unknown,
-  ) {
-    const history = this.intermediateValuesByElementProp
-      .get(elementId)
-      ?.get(prop);
-    if (!history) {
-      return false;
-    }
-
-    return history.contains(candidate);
-  }
-}

packages/excalidraw/types.ts

@@ -315,7 +315,10 @@ export interface AppState {
   bindingPreference: "enabled" | "disabled";
   /** user preference whether arrow snap to midpoints while binding */
   isMidpointSnappingEnabled: boolean;
-  startBoundElement: NonDeleted<ExcalidrawBindableElement> | null;
+  /**
+   * The bindable element the UI highlights for the user when an arrow is
+   * dragged or otherwise its endpoint being close to said element.
+   */
   suggestedBinding: {
     element: NonDeleted<ExcalidrawBindableElement>;
     midPoint?: GlobalPoint;
@@ -347,8 +350,11 @@ export interface AppState {
     type: "selection" | "lasso";
     initialized: boolean;
   };
+
+  // Pen handling
   penMode: boolean;
   penDetected: boolean;
+
   exportBackground: boolean;
   exportEmbedScene: boolean;
   exportWithDarkMode: boolean;
@@ -472,6 +478,9 @@ export interface AppState {
   // as elements are unlocked, we remove the groupId from the elements
   // and also remove groupId from this map
   lockedMultiSelections: { [groupId: string]: true };
+  // Stores the current bind mode which is detemined at various points during
+  // a drag operation (like pointer position vs bindable element) but needed
+  // globally for calculating the binding strategy
   bindMode: BindMode;
 }
 
@@ -487,10 +496,7 @@ export type SearchMatch = {
   }[];
 };
 
-export type UIAppState = Omit<
+export type UIAppState = Omit<AppState, "cursorButton" | "scrollX" | "scrollY">;
-  AppState,
-  "startBoundElement" | "cursorButton" | "scrollX" | "scrollY"
->;
 
 export type NormalizedZoomValue = number & { _brand: "normalizedZoom" };
 
@@ -796,9 +802,6 @@ export type AppClassProperties = {
   files: BinaryFiles;
   editorInterface: App["editorInterface"];
   scene: App["scene"];
-  store: App["store"];
-  transactionManager: App["transactionManager"];
-  createTransaction: App["createTransaction"];
   syncActionResult: App["syncActionResult"];
   fonts: App["fonts"];
   pasteFromClipboard: App["pasteFromClipboard"];
@@ -873,8 +876,13 @@ export type PointerDownState = Readonly<{
     // Whether selected element(s) were duplicated, might change during the
     // pointer interaction
     hasBeenDuplicated: boolean;
+    // Whether the pointer is hitting the common bounding box of selected
+    // elements, which is useful for discriminating between selecitng
+    // the entire selection vs a specific element
     hasHitCommonBoundingBoxOfSelectedElements: boolean;
   };
+  // This is determined on the initial pointer down event to
+  // set various interaction modalities
   withCmdOrCtrl: boolean;
   drag: {
     // Might change during the pointer interaction
@@ -900,6 +908,7 @@ export type PointerDownState = Readonly<{
     onKeyUp: null | ((event: KeyboardEvent) => void);
   };
   boxSelection: {
+    // If the box selection tool is activated on pointer down
     hasOccurred: boolean;
   };
 }>;

packages/math/src/constants.ts

@@ -1,5 +1,3 @@
-export const PRECISION = 10e-5;
-
 // Legendre-Gauss abscissae (x values) and weights for n=24
 // Refeerence: https://pomax.github.io/bezierinfo/legendre-gauss.html
 export const LegendreGaussN24TValues = [

packages/utils/tests/__snapshots__/export.test.ts.snap

@@ -98,7 +98,6 @@ exports[`exportToSvg > with default arguments 1`] = `
   "showHyperlinkPopup": false,
   "showWelcomeScreen": false,
   "snapLines": [],
-  "startBoundElement": null,
   "stats": {
     "open": false,
     "panels": 3,