Merge branch 'master' into mtolmacs/fix/grid-binding

Signed-off-by: Mark Tolmacs <mark@lazycat.hu>

packages/common/src/points.ts

@@ -1,4 +1,5 @@
 import {
+  pointFrom,
   pointFromPair,
   type GlobalPoint,
   type LocalPoint,
@@ -69,12 +70,12 @@ export const getGridPoint = (
   x: number,
   y: number,
   gridSize: NullableGridSize,
-): [number, number] => {
+): GlobalPoint => {
   if (gridSize) {
-    return [
+    return pointFrom<GlobalPoint>(
       Math.round(x / gridSize) * gridSize,
       Math.round(y / gridSize) * gridSize,
-    ];
+    );
   }
-  return [x, y];
+  return pointFrom<GlobalPoint>(x, y);
 };

packages/element/src/__tests__/__snapshots__/transform.test.ts.snap

@@ -1822,7 +1822,7 @@ exports[`Test Transform > should transform the elements correctly when linear el
   "versionNonce": Any<Number>,
   "verticalAlign": "middle",
   "width": 120,
-  "x": 187.7545,
+  "x": 187.75450000000004,
   "y": 44.5,
 }
 `;

packages/element/src/binding.ts

@@ -1,6 +1,7 @@
 import {
   arrayToMap,
   getFeatureFlag,
+  getGridPoint,
   invariant,
   isTransparent,
 } from "@excalidraw/common";
@@ -22,7 +23,7 @@ import {
 } from "@excalidraw/math";
 
 import type { LineSegment, LocalPoint, Radians } from "@excalidraw/math";
-import type { AppState } from "@excalidraw/excalidraw/types";
+import type { AppState, NullableGridSize } from "@excalidraw/excalidraw/types";
 import type { MapEntry, Mutable } from "@excalidraw/common/utility-types";
 import type { Bounds } from "@excalidraw/common";
 
@@ -154,6 +155,7 @@ export const bindOrUnbindBindingElement = (
     altKey?: boolean;
     angleLocked?: boolean;
     initialBinding?: boolean;
+    gridSize?: NullableGridSize;
   },
 ) => {
   const { start, end } = getBindingStrategyForDraggingBindingElementEndpoints(
@@ -170,12 +172,16 @@ export const bindOrUnbindBindingElement = (
     },
   );
 
+  const isMidpointSnappingEnabled =
+    appState.isMidpointSnappingEnabled && !appState.gridModeEnabled;
+
   bindOrUnbindBindingElementEdge(
     arrow,
     start,
     "start",
     scene,
     appState.isBindingEnabled,
+    isMidpointSnappingEnabled,
   );
   bindOrUnbindBindingElementEdge(
     arrow,
@@ -183,6 +189,7 @@ export const bindOrUnbindBindingElement = (
     "end",
     scene,
     appState.isBindingEnabled,
+    isMidpointSnappingEnabled,
   );
   if (start.focusPoint || end.focusPoint) {
     // If the strategy dictates a focus point override, then
@@ -227,6 +234,7 @@ const bindOrUnbindBindingElementEdge = (
   startOrEnd: "start" | "end",
   scene: Scene,
   shouldSnapToOutline = true,
+  isMidpointSnappingEnabled = true,
 ): void => {
   if (mode === null) {
     // null means break the binding
@@ -240,6 +248,7 @@ const bindOrUnbindBindingElementEdge = (
       scene,
       focusPoint,
       shouldSnapToOutline,
+      isMidpointSnappingEnabled,
     );
   }
 };
@@ -593,6 +602,7 @@ export const getBindingStrategyForDraggingBindingElementEndpoints = (
     finalize?: boolean;
     initialBinding?: boolean;
     zoom?: AppState["zoom"];
+    gridSize?: NullableGridSize;
   },
 ): { start: BindingStrategy; end: BindingStrategy } => {
   if (getFeatureFlag("COMPLEX_BINDINGS")) {
@@ -633,6 +643,7 @@ const getBindingStrategyForDraggingBindingElementEndpoints_simple = (
     finalize?: boolean;
     initialBinding?: boolean;
     zoom?: AppState["zoom"];
+    gridSize?: NullableGridSize;
   },
 ): { start: BindingStrategy; end: BindingStrategy } => {
   const startIdx = 0;
@@ -695,7 +706,9 @@ const getBindingStrategyForDraggingBindingElementEndpoints_simple = (
     elementsMap,
   );
   const hit = getHoveredElementForBinding(
-    globalPoint,
+    opts?.angleLocked || appState.gridModeEnabled
+      ? pointFrom<GlobalPoint>(scenePointerX, scenePointerY)
+      : globalPoint,
     elements,
     elementsMap,
     maxBindingDistance_simple(appState.zoom),
@@ -747,7 +760,11 @@ const getBindingStrategyForDraggingBindingElementEndpoints_simple = (
           ? globalPoint
           : // NOTE: Can only affect the start point because new arrows always drag the end point
           opts?.newArrow
-          ? appState.selectedLinearElement!.initialState.origin!
+          ? getGridPoint(
+              appState.selectedLinearElement!.initialState.origin![0],
+              appState.selectedLinearElement!.initialState.origin![1],
+              opts.gridSize as NullableGridSize,
+            )
           : LinearElementEditor.getPointAtIndexGlobalCoordinates(
               arrow,
               0,
@@ -806,12 +823,27 @@ const getBindingStrategyForDraggingBindingElementEndpoints_simple = (
           focusPoint:
             projectFixedPointOntoDiagonal(
               arrow,
-              globalPoint,
+              opts?.angleLocked || appState.gridModeEnabled
+                ? snapBoundPointToGrid(
+                    pointFrom<GlobalPoint>(scenePointerX, scenePointerY),
+                    hit,
+                    elementsMap,
+                    appState.gridSize as NullableGridSize,
+                    arrow,
+                    LinearElementEditor.getPointAtIndexGlobalCoordinates(
+                      arrow,
+                      startDragged ? 1 : -2,
+                      elementsMap,
+                    ),
+                  )
+                : globalPoint,
               hit,
               startDragged ? "start" : "end",
               elementsMap,
               appState.zoom,
-              appState.isMidpointSnappingEnabled,
+              appState.isMidpointSnappingEnabled &&
+                !opts?.angleLocked &&
+                !appState.gridModeEnabled,
             ) || globalPoint,
         }
     : { mode: null };
@@ -856,7 +888,7 @@ const getBindingStrategyForDraggingBindingElementEndpoints_simple = (
               startDragged ? "end" : "start",
               elementsMap,
               appState.zoom,
-              appState.isMidpointSnappingEnabled,
+              false,
             ) || otherEndpoint,
         }
       : { mode: undefined }
@@ -1021,6 +1053,7 @@ export const bindBindingElement = (
   scene: Scene,
   focusPoint?: GlobalPoint,
   shouldSnapToOutline = true,
+  isMidpointSnappingEnabled = true,
 ): void => {
   const elementsMap = scene.getNonDeletedElementsMap();
 
@@ -1036,6 +1069,7 @@ export const bindBindingElement = (
         startOrEnd,
         elementsMap,
         shouldSnapToOutline,
+        isMidpointSnappingEnabled,
       ),
     };
   } else {
@@ -1740,6 +1774,92 @@ const extractBinding = (
   };
 };
 
+/**
+ * Snaps a bound arrow endpoint to the grid on the axis parallel to the
+ * bindable element's side, while preserving the binding gap distance on the
+ * perpendicular axis. In other words, the grid axis closest to the side's
+ * perpendicular (normal) is used as the snap axis and the other axis is kept at
+ * the binding gap distance.
+ */
+const snapBoundPointToGrid = (
+  outlinePoint: GlobalPoint,
+  bindableElement: ExcalidrawBindableElement,
+  elementsMap: ElementsMap,
+  gridSize: NullableGridSize,
+  arrowElement: ExcalidrawArrowElement,
+  adjacentPoint?: GlobalPoint,
+): GlobalPoint => {
+  if (!gridSize) {
+    return outlinePoint;
+  }
+
+  const aabb = aabbForElement(bindableElement, elementsMap);
+  // For ellipses and diamonds use the arrow's incoming direction instead of
+  // the position-based heading, which can give the wrong axis when the
+  // outline point is near a cardinal zone or an angled diamond face.
+  const heading =
+    adjacentPoint &&
+    (bindableElement.type === "ellipse" || bindableElement.type === "diamond")
+      ? vectorToHeading(vectorFromPoint(adjacentPoint, outlinePoint))
+      : headingForPointFromElement(bindableElement, aabb, outlinePoint);
+
+  const normalLocal = pointFrom<GlobalPoint>(heading[0], heading[1]);
+  const normalGlobal = pointRotateRads(
+    normalLocal,
+    pointFrom<GlobalPoint>(0, 0),
+    bindableElement.angle,
+  );
+
+  const bindingGap = getBindingGap(bindableElement, arrowElement);
+  const extent =
+    Math.max(bindableElement.width, bindableElement.height) + bindingGap * 2;
+  const center = getCenterForBounds(aabb);
+
+  const absNX = Math.abs(normalGlobal[0]);
+  const absNY = Math.abs(normalGlobal[1]);
+  if (absNX >= absNY) {
+    // Global X is closest to the perpendicular so snap Y, intersect horizontal line
+    const [, snappedY] = getGridPoint(
+      outlinePoint[0],
+      outlinePoint[1],
+      gridSize,
+    );
+    const intersector = lineSegment<GlobalPoint>(
+      pointFrom<GlobalPoint>(center[0] - extent, snappedY),
+      pointFrom<GlobalPoint>(center[0] + extent, snappedY),
+    );
+    const intersection = intersectElementWithLineSegment(
+      bindableElement,
+      elementsMap,
+      intersector,
+      bindingGap,
+    ).sort(
+      (a, b) =>
+        pointDistanceSq(a, outlinePoint) - pointDistanceSq(b, outlinePoint),
+    )[0];
+
+    return intersection ?? pointFrom<GlobalPoint>(outlinePoint[0], snappedY);
+  }
+
+  // Global Y is closest to the perpendicular so snap X, intersect vertical line
+  const [snappedX] = getGridPoint(outlinePoint[0], outlinePoint[1], gridSize);
+  const intersector = lineSegment<GlobalPoint>(
+    pointFrom<GlobalPoint>(snappedX, center[1] - extent),
+    pointFrom<GlobalPoint>(snappedX, center[1] + extent),
+  );
+  const intersection = intersectElementWithLineSegment(
+    bindableElement,
+    elementsMap,
+    intersector,
+    bindingGap,
+  ).sort(
+    (a, b) =>
+      pointDistanceSq(a, outlinePoint) - pointDistanceSq(b, outlinePoint),
+  )[0];
+
+  return intersection ?? pointFrom<GlobalPoint>(snappedX, outlinePoint[1]);
+};
+
 const elementArea = (element: ExcalidrawBindableElement) =>
   element.width * element.height;
 

packages/element/src/bounds.ts

@@ -790,41 +790,27 @@ export const getArrowheadPoints = (
     p0 = pointFrom(prevOp.data[4], prevOp.data[5]);
   }
 
-  // We know the last point of the arrow (or the first, if start arrowhead).
+  // B(t) = p0 * (1-t)^3 + 3p1 * t * (1-t)^2 + 3p2 * t^2 * (1-t) + p3 * t^3
+  const equation = (t: number, idx: number) =>
+    Math.pow(1 - t, 3) * p3[idx] +
+    3 * t * Math.pow(1 - t, 2) * p2[idx] +
+    3 * Math.pow(t, 2) * (1 - t) * p1[idx] +
+    p0[idx] * Math.pow(t, 3);
+
+  // Ee know the last point of the arrow (or the first, if start arrowhead).
   const [x2, y2] = position === "start" ? p0 : p3;
 
-  // Use the analytic tangent at the Bézier endpoint for a precise arrowhead
-  // direction. For a cubic Bézier B(t) with control points p0p3:
-  //   B'(1): (p3 − p2) tangent at the end
-  //   B'(0): (p1 − p0) for start arrowhead, arrow points away: (p0 − p1)
-  let dx: number;
-  let dy: number;
-  if (position === "end") {
-    dx = p3[0] - p2[0];
-    dy = p3[1] - p2[1];
-    if (Math.hypot(dx, dy) < 1e-6) {
-      dx = p3[0] - p1[0];
-      dy = p3[1] - p1[1];
-    }
-    if (Math.hypot(dx, dy) < 1e-6) {
-      dx = p3[0] - p0[0];
-      dy = p3[1] - p0[1];
-    }
-  } else {
-    dx = p0[0] - p1[0];
-    dy = p0[1] - p1[1];
-    if (Math.hypot(dx, dy) < 1e-6) {
-      dx = p0[0] - p2[0];
-      dy = p0[1] - p2[1];
-    }
-    if (Math.hypot(dx, dy) < 1e-6) {
-      dx = p0[0] - p3[0];
-      dy = p0[1] - p3[1];
-    }
-  }
-  const distance = Math.hypot(dx, dy);
-  const nx = dx / distance;
-  const ny = dy / distance;
+  // By using cubic bezier equation (B(t)) and the given parameters,
+  // we calculate a point that is closer to the last point.
+  // The value 0.3 is chosen arbitrarily and it works best for all
+  // the tested cases.
+  const [x1, y1] = [equation(0.3, 0), equation(0.3, 1)];
+
+  // Find the normalized direction vector based on the
+  // previously calculated points.
+  const distance = Math.hypot(x2 - x1, y2 - y1);
+  const nx = (x2 - x1) / distance;
+  const ny = (y2 - y1) / distance;
 
   const size = getArrowheadSize(arrowhead);
 
@@ -894,10 +880,30 @@ export const getArrowheadPoints = (
   );
 
   if (arrowhead === "diamond" || arrowhead === "diamond_outline") {
-    // point opposite to the arrowhead point, just mirrored across the (tx, ty)
-    // point
-    const ox = tx - nx * minSize * 2;
-    const oy = ty - ny * minSize * 2;
+    // point opposite to the arrowhead point
+    let ox;
+    let oy;
+
+    if (position === "start") {
+      const [px, py] = element.points.length > 1 ? element.points[1] : [0, 0];
+
+      [ox, oy] = pointRotateRads(
+        pointFrom(tx + minSize * 2, ty),
+        pointFrom(tx, ty),
+        Math.atan2(py - ty, px - tx) as Radians,
+      );
+    } else {
+      const [px, py] =
+        element.points.length > 1
+          ? element.points[element.points.length - 2]
+          : [0, 0];
+
+      [ox, oy] = pointRotateRads(
+        pointFrom(tx - minSize * 2, ty),
+        pointFrom(tx, ty),
+        Math.atan2(ty - py, tx - px) as Radians,
+      );
+    }
 
     return [tx, ty, x3, y3, ox, oy, x4, y4];
   }

packages/element/src/linearElementEditor.ts

@@ -359,6 +359,7 @@ export class LinearElementEditor {
       linearElementEditor,
     );
 
+    const angleLocked = shouldRotateWithDiscreteAngle(event);
     LinearElementEditor.movePoints(
       element,
       app.scene,
@@ -370,7 +371,10 @@ export class LinearElementEditor {
       },
       {
         isBindingEnabled: app.state.isBindingEnabled,
-        isMidpointSnappingEnabled: app.state.isMidpointSnappingEnabled,
+        isMidpointSnappingEnabled:
+          app.state.isMidpointSnappingEnabled &&
+          !angleLocked &&
+          !app.state.gridModeEnabled,
       },
     );
     // Set the suggested binding from the updates if available
@@ -427,7 +431,9 @@ export class LinearElementEditor {
                 "start",
                 elementsMap,
                 app.state.zoom,
-                app.state.isMidpointSnappingEnabled,
+                app.state.isMidpointSnappingEnabled &&
+                  !angleLocked &&
+                  !app.state.gridModeEnabled,
               )
             : linearElementEditor.initialState.altFocusPoint,
       },
@@ -554,6 +560,8 @@ export class LinearElementEditor {
       linearElementEditor,
     );
 
+    const angleLocked =
+      shouldRotateWithDiscreteAngle(event) && singlePointDragged;
     LinearElementEditor.movePoints(
       element,
       app.scene,
@@ -565,7 +573,10 @@ export class LinearElementEditor {
       },
       {
         isBindingEnabled: app.state.isBindingEnabled,
-        isMidpointSnappingEnabled: app.state.isMidpointSnappingEnabled,
+        isMidpointSnappingEnabled:
+          app.state.isMidpointSnappingEnabled &&
+          !angleLocked &&
+          !app.state.gridModeEnabled,
       },
     );
 
@@ -661,7 +672,9 @@ export class LinearElementEditor {
                 "start",
                 elementsMap,
                 app.state.zoom,
-                app.state.isMidpointSnappingEnabled,
+                app.state.isMidpointSnappingEnabled &&
+                  !angleLocked &&
+                  !app.state.gridModeEnabled,
               )
             : linearElementEditor.initialState.altFocusPoint,
       },
@@ -790,20 +803,9 @@ export class LinearElementEditor {
       elementsMap,
     );
 
-    const [lines, segCurves] = deconstructLinearOrFreeDrawElement(
-      element,
-      elementsMap,
-    );
-    const segmentCount = lines.length + segCurves.length;
-
     let index = 0;
     const midpoints: (GlobalPoint | null)[] = [];
     while (index < points.length - 1) {
-      if (segmentCount > 0 && index >= segmentCount) {
-        midpoints.push(null);
-        index++;
-        continue;
-      }
       if (
         LinearElementEditor.isSegmentTooShort(
           element,
@@ -2187,6 +2189,7 @@ const pointDraggingUpdates = (
       newArrow: !!app.state.newElement,
       angleLocked,
       altKey,
+      gridSize: app.getEffectiveGridSize(),
     },
   );
 

packages/element/src/shape.ts

@@ -78,18 +78,6 @@ import type {
 import type { Drawable, Options } from "roughjs/bin/core";
 import type { Point as RoughPoint } from "roughjs/bin/geometry";
 
-// Controls how handle distance scales with chord length.
-// At 1.0 handles are exactly h/3 (standard Hermite). Values below 1 make
-// short segments curvier and long segments more taut (sub-linear scaling).
-const CP_CHORD_POWER = 1;
-
-// At curved knots the C2 spline tangent can be tilted away from the
-// bisector direction, making one side of the knot tight and the other taut.
-// This factor [0, 1] controls how far the tangent direction is pulled toward
-// the bisector (the chord-bisector normal) linearly with turn sharpness.
-// 0 = pure C2 spline; 1 = tangent fully aligned with the bisector.
-const CP_ANGLE_CORRECTION = 1;
-
 export class ShapeCache {
   private static rg = new RoughGenerator();
   private static cache = new WeakMap<
@@ -637,144 +625,60 @@ export const generateLinearCollisionShape = (
         });
       }
 
-      // Generate collision ops using the same bisector-based cubic Bézier
-      // algorithm as generateRoundedSimpleArrowShape so hit-testing matches rendering.
-      const rotateLocal = (lx: number, ly: number): LocalPoint => {
-        const g = pointRotateRads<GlobalPoint>(
-          pointFrom<GlobalPoint>(element.x + lx, element.y + ly),
-          center,
-          element.angle,
-        );
-        return pointFrom<LocalPoint>(g[0] - element.x, g[1] - element.y);
-      };
+      return generator
+        .curve(points as unknown as RoughPoint[], options)
+        .sets[0].ops.slice(0, element.points.length)
+        .map((op, i) => {
+          if (i === 0) {
+            const p = pointRotateRads<GlobalPoint>(
+              pointFrom<GlobalPoint>(
+                element.x + op.data[0],
+                element.y + op.data[1],
+              ),
+              center,
+              element.angle,
+            );
 
-      const collisionOps: Array<{
-        op: string;
-        data: number[] | LocalPoint;
-      }> = [];
-      collisionOps.push({
-        op: "move",
-        data: rotateLocal(points[0][0], points[0][1]),
-      });
-
-      if (points.length === 2) {
-        collisionOps.push({
-          op: "lineTo",
-          data: rotateLocal(points[1][0], points[1][1]),
-        });
-      } else {
-        // Chord-length C2 spline. Mirrors generateRoundedSimpleArrowShape
-        // exactly so hit-testing matches rendering.
-        const n = points.length - 1;
-        const h = new Float64Array(n);
-        for (let i = 0; i < n; i++) {
-          h[i] = Math.max(
-            1e-10,
-            Math.hypot(
-              points[i + 1][0] - points[i][0],
-              points[i + 1][1] - points[i][1],
-            ),
-          );
-        }
-
-        const mx = new Float64Array(n + 1);
-        const my = new Float64Array(n + 1);
-        const diag = new Float64Array(n + 1);
-        const rhsX = new Float64Array(n + 1);
-        const rhsY = new Float64Array(n + 1);
-
-        diag[0] = 2;
-        rhsX[0] = (3 * (points[1][0] - points[0][0])) / h[0];
-        rhsY[0] = (3 * (points[1][1] - points[0][1])) / h[0];
-        for (let i = 1; i < n; i++) {
-          diag[i] = 2 * (h[i - 1] + h[i]);
-          rhsX[i] =
-            3 *
-            ((h[i] * (points[i][0] - points[i - 1][0])) / h[i - 1] +
-              (h[i - 1] * (points[i + 1][0] - points[i][0])) / h[i]);
-          rhsY[i] =
-            3 *
-            ((h[i] * (points[i][1] - points[i - 1][1])) / h[i - 1] +
-              (h[i - 1] * (points[i + 1][1] - points[i][1])) / h[i]);
-        }
-        diag[n] = 2;
-        rhsX[n] = (3 * (points[n][0] - points[n - 1][0])) / h[n - 1];
-        rhsY[n] = (3 * (points[n][1] - points[n - 1][1])) / h[n - 1];
-
-        for (let i = 1; i <= n; i++) {
-          const sub = i < n ? h[i] : 1;
-          const supPrev = i === 1 ? 1 : h[i - 2];
-          const w = sub / diag[i - 1];
-          diag[i] -= w * supPrev;
-          rhsX[i] -= w * rhsX[i - 1];
-          rhsY[i] -= w * rhsY[i - 1];
-        }
-        mx[n] = rhsX[n] / diag[n];
-        my[n] = rhsY[n] / diag[n];
-        for (let i = n - 1; i >= 0; i--) {
-          const sup = i === 0 ? 1 : h[i - 1];
-          mx[i] = (rhsX[i] - sup * mx[i + 1]) / diag[i];
-          my[i] = (rhsY[i] - sup * my[i + 1]) / diag[i];
-        }
-
-        // Normalised tangent directions; handle length scales sub-linearly with chord.
-        const mlen = new Float64Array(n + 1);
-        for (let i = 0; i <= n; i++) {
-          mlen[i] = Math.max(1e-10, Math.hypot(mx[i], my[i]));
-        }
-
-        // At interior knots, blend the C2 tangent direction toward the
-        // bisector direction by a factor proportional to turn sharpness *
-        // CP_ANGLE_CORRECTION
-        for (let k = 1; k < n; k++) {
-          const d1x = (points[k][0] - points[k - 1][0]) / h[k - 1];
-          const d1y = (points[k][1] - points[k - 1][1]) / h[k - 1];
-          const d2x = (points[k + 1][0] - points[k][0]) / h[k];
-          const d2y = (points[k + 1][1] - points[k][1]) / h[k];
-          const dot = d1x * d2x + d1y * d2y;
-          const t = ((1 - dot) / 2) * CP_ANGLE_CORRECTION;
-          if (t < 1e-6) {
-            continue;
+            return {
+              op: "move",
+              data: pointFrom<LocalPoint>(p[0] - element.x, p[1] - element.y),
+            };
           }
-          const bx = d1x + d2x;
-          const by = d1y + d2y;
-          const blen = Math.hypot(bx, by);
-          if (blen < 1e-10) {
-            continue;
-          }
-          let px = bx / blen;
-          let py = by / blen;
-          const tx = mx[k] / mlen[k];
-          const ty = my[k] / mlen[k];
-          if (tx * px + ty * py < 0) {
-            px = -px;
-            py = -py;
-          }
-          const blendX = tx + t * (px - tx);
-          const blendY = ty + t * (py - ty);
-          const blendLen = Math.max(1e-10, Math.hypot(blendX, blendY));
-          mx[k] = (blendX / blendLen) * mlen[k];
-          my[k] = (blendY / blendLen) * mlen[k];
-        }
 
-        for (let i = 0; i < n; i++) {
-          const cpDist = Math.pow(h[i], CP_CHORD_POWER) / 3;
-          const cp1x = points[i][0] + (mx[i] / mlen[i]) * cpDist;
-          const cp1y = points[i][1] + (my[i] / mlen[i]) * cpDist;
-          const cp2x = points[i + 1][0] - (mx[i + 1] / mlen[i + 1]) * cpDist;
-          const cp2y = points[i + 1][1] - (my[i + 1] / mlen[i + 1]) * cpDist;
-
-          const rcp1 = rotateLocal(cp1x, cp1y);
-          const rcp2 = rotateLocal(cp2x, cp2y);
-          const rend = rotateLocal(points[i + 1][0], points[i + 1][1]);
-
-          collisionOps.push({
+          return {
             op: "bcurveTo",
-            data: [rcp1[0], rcp1[1], rcp2[0], rcp2[1], rend[0], rend[1]],
-          });
-        }
-      }
-      return collisionOps;
+            data: [
+              pointRotateRads(
+                pointFrom<GlobalPoint>(
+                  element.x + op.data[0],
+                  element.y + op.data[1],
+                ),
+                center,
+                element.angle,
+              ),
+              pointRotateRads(
+                pointFrom<GlobalPoint>(
+                  element.x + op.data[2],
+                  element.y + op.data[3],
+                ),
+                center,
+                element.angle,
+              ),
+              pointRotateRads(
+                pointFrom<GlobalPoint>(
+                  element.x + op.data[4],
+                  element.y + op.data[5],
+                ),
+                center,
+                element.angle,
+              ),
+            ]
+              .map((p) =>
+                pointFrom<LocalPoint>(p[0] - element.x, p[1] - element.y),
+              )
+              .flat(),
+          };
+        });
     }
     case "freedraw": {
       if (element.points.length < 2) {
@@ -1016,12 +920,7 @@ const _generateElementShape = (
           ];
         }
       } else {
-        shape = [
-          generator.path(
-            generateRoundedSimpleArrowShape(points),
-            generateRoughOptions(element, true, isDarkMode),
-          ),
-        ];
+        shape = [generator.curve(points as unknown as RoughPoint[], options)];
       }
 
       // add lines only in arrow
@@ -1105,162 +1004,10 @@ const _generateElementShape = (
   }
 };
 
-const generateRoundedSimpleArrowShape = (
-  points: readonly LocalPoint[],
-): string => {
-  if (points.length < 2) {
-    return "";
-  }
-
-  if (points.length === 2) {
-    return `M ${points[0][0]} ${points[0][1]} L ${points[1][0]} ${points[1][1]}`;
-  }
-
-  // Chord-length parameterised C2 natural cubic spline (Thomas's algorithm).
-  //
-  // Unknowns: tangent vectors m[0..n] at each knot (n = number of segments).
-  // Chord lengths h[i] = |K[i+1] − K[i]| act as the parameter intervals so
-  // that tightly-spaced knots don't over-influence distant ones.
-  //
-  //   Row 0:         2·m₀  +           m₁              = 3·(K₁−K₀)/h₀
-  //   Row i:  h[i]·mᵢ₋₁ + 2·(h[i−1]+h[i])·mᵢ + h[i−1]·mᵢ₊₁
-  //                                   = 3·(h[i]·(Kᵢ−Kᵢ₋₁)/h[i−1]
-  //                                      + h[i−1]·(Kᵢ₊₁−Kᵢ)/h[i])  1≤i≤n−1
-  //   Row n:           mₙ₋₁ +  2·mₙ                    = 3·(Kₙ−Kₙ₋₁)/h[n−1]
-  //
-  // Bézier control points from Hermite→Bézier identity:
-  //   cp1ᵢ = Kᵢ   + mᵢ   · h[i] / 3
-  //   cp2ᵢ = Kᵢ₊₁ − mᵢ₊₁ · h[i] / 3
-  const n = points.length - 1; // number of segments
-  const h = new Float64Array(n);
-  for (let i = 0; i < n; i++) {
-    h[i] = Math.max(
-      1e-10,
-      Math.hypot(
-        points[i + 1][0] - points[i][0],
-        points[i + 1][1] - points[i][1],
-      ),
-    );
-  }
-
-  const mx = new Float64Array(n + 1);
-  const my = new Float64Array(n + 1);
-  const diag = new Float64Array(n + 1);
-  const rhsX = new Float64Array(n + 1);
-  const rhsY = new Float64Array(n + 1);
-
-  // Row 0 – natural BC (zero second derivative at start)
-  diag[0] = 2;
-  rhsX[0] = (3 * (points[1][0] - points[0][0])) / h[0];
-  rhsY[0] = (3 * (points[1][1] - points[0][1])) / h[0];
-
-  // Interior rows
-  for (let i = 1; i < n; i++) {
-    diag[i] = 2 * (h[i - 1] + h[i]);
-    rhsX[i] =
-      3 *
-      ((h[i] * (points[i][0] - points[i - 1][0])) / h[i - 1] +
-        (h[i - 1] * (points[i + 1][0] - points[i][0])) / h[i]);
-    rhsY[i] =
-      3 *
-      ((h[i] * (points[i][1] - points[i - 1][1])) / h[i - 1] +
-        (h[i - 1] * (points[i + 1][1] - points[i][1])) / h[i]);
-  }
-
-  // Row n – natural BC (zero second derivative at end)
-  diag[n] = 2;
-  rhsX[n] = (3 * (points[n][0] - points[n - 1][0])) / h[n - 1];
-  rhsY[n] = (3 * (points[n][1] - points[n - 1][1])) / h[n - 1];
-
-  // Forward sweep
-  // sub[i] = h[i] for i=1..n−1, sub[n] = 1
-  // sup[i] = 1 for i=0, h[i−1] for i=1..n−1  (never modified)
-  for (let i = 1; i <= n; i++) {
-    const sub = i < n ? h[i] : 1;
-    const supPrev = i === 1 ? 1 : h[i - 2];
-    const w = sub / diag[i - 1];
-    diag[i] -= w * supPrev;
-    rhsX[i] -= w * rhsX[i - 1];
-    rhsY[i] -= w * rhsY[i - 1];
-  }
-
-  // Back substitution
-  mx[n] = rhsX[n] / diag[n];
-  my[n] = rhsY[n] / diag[n];
-  for (let i = n - 1; i >= 0; i--) {
-    const sup = i === 0 ? 1 : h[i - 1];
-    mx[i] = (rhsX[i] - sup * mx[i + 1]) / diag[i];
-    my[i] = (rhsY[i] - sup * my[i + 1]) / diag[i];
-  }
-
-  // Normalised tangent directions; handle length scales sub-linearly with chord.
-  const mlen = new Float64Array(n + 1);
-  for (let i = 0; i <= n; i++) {
-    mlen[i] = Math.max(1e-10, Math.hypot(mx[i], my[i]));
-  }
-
-  // At interior knots, blend the C2 tangent direction toward the
-  // perpendicular-to-bisector (the perfectly symmetric tangent) by a factor
-  // proportional to turn sharpness × CP_ANGLE_CORRECTION.
-  // Both cp2 (incoming) and cp1 (outgoing) at the knot share the same adjusted
-  // direction, so collinear (aligned) handles are preserved.
-  for (let k = 1; k < n; k++) {
-    const d1x = (points[k][0] - points[k - 1][0]) / h[k - 1];
-    const d1y = (points[k][1] - points[k - 1][1]) / h[k - 1];
-    const d2x = (points[k + 1][0] - points[k][0]) / h[k];
-    const d2y = (points[k + 1][1] - points[k][1]) / h[k];
-    const dot = d1x * d2x + d1y * d2y;
-    // t: 0 = straight, 1 = hairpin
-    const t = ((1 - dot) / 2) * CP_ANGLE_CORRECTION;
-    if (t < 1e-6) {
-      continue;
-    }
-    // Bisector of the two chord directions as the "normal" at the knot.
-    // Its perpendicular is the ideal symmetric tangent direction.
-    const bx = d1x + d2x;
-    const by = d1y + d2y;
-    const blen = Math.hypot(bx, by);
-    if (blen < 1e-10) {
-      continue; // 180° hairpin – bisector undefined, skip
-    }
-    // Blend target: bisector direction (pick sign aligning with current tangent)
-    let px = bx / blen;
-    let py = by / blen;
-    const tx = mx[k] / mlen[k];
-    const ty = my[k] / mlen[k];
-    if (tx * px + ty * py < 0) {
-      px = -px;
-      py = -py;
-    }
-    // Linear blend of unit directions, then renormalize to preserve magnitude.
-    const blendX = tx + t * (px - tx);
-    const blendY = ty + t * (py - ty);
-    const blendLen = Math.max(1e-10, Math.hypot(blendX, blendY));
-    mx[k] = (blendX / blendLen) * mlen[k];
-    my[k] = (blendY / blendLen) * mlen[k];
-  }
-
-  const path: string[] = [`M ${points[0][0]} ${points[0][1]}`];
-  for (let i = 0; i < n; i++) {
-    const cpDist = Math.pow(h[i], CP_CHORD_POWER) / 3;
-    const cp1x = points[i][0] + (mx[i] / mlen[i]) * cpDist;
-    const cp1y = points[i][1] + (my[i] / mlen[i]) * cpDist;
-    const cp2x = points[i + 1][0] - (mx[i + 1] / mlen[i + 1]) * cpDist;
-    const cp2y = points[i + 1][1] - (my[i + 1] / mlen[i + 1]) * cpDist;
-    path.push(
-      `C ${cp1x} ${cp1y} ${cp2x} ${cp2y} ${points[i + 1][0]} ${
-        points[i + 1][1]
-      }`,
-    );
-  }
-
-  return path.join(" ");
-};
-
 const generateElbowArrowShape = (
   points: readonly LocalPoint[],
   radius: number,
-): string => {
+) => {
   const subpoints = [] as [number, number][];
   for (let i = 1; i < points.length - 1; i += 1) {
     const prev = points[i - 1];

packages/element/tests/bounds.test.ts

@@ -135,9 +135,9 @@ describe("getElementBounds", () => {
     } as ExcalidrawLinearElement;
 
     const [x1, y1, x2, y2] = getElementBounds(element, arrayToMap([element]));
-    expect(x1).toEqual(366.0476290709661);
-    expect(y1).toEqual(186.59818534770224);
-    expect(x2).toEqual(494.6034220048372);
-    expect(y2).toEqual(324.16489799221546);
+    expect(x1).toEqual(360.9291017525165);
+    expect(y1).toEqual(185.24770129343722);
+    expect(x2).toEqual(481.4815539037601);
+    expect(y2).toEqual(319.8162855827246);
   });
 });

packages/element/tests/collision.test.tsx

@@ -30,7 +30,7 @@ describe("check rotated elements can be hit:", () => {
       ] as LocalPoint[],
     });
     const hit = hitElementItself({
-      point: pointFrom<GlobalPoint>(90, -70),
+      point: pointFrom<GlobalPoint>(88, -68),
       element: window.h.elements[0],
       threshold: 10,
       elementsMap: window.h.scene.getNonDeletedElementsMap(),

packages/element/tests/linearElementEditor.test.tsx

@@ -434,12 +434,12 @@ describe("Test Linear Elements", () => {
       expect(midPointsWithRoundEdge).toMatchInlineSnapshot(`
         [
           [
-            "51.36383",
-            "54.86323",
+            "54.27552",
+            "46.16120",
           ],
           [
-            "81.64884",
-            "43.04575",
+            "76.95494",
+            "44.56052",
           ],
         ]
       `);
@@ -499,12 +499,12 @@ describe("Test Linear Elements", () => {
       expect(newMidPoints).toMatchInlineSnapshot(`
         [
           [
-            "101.36383",
-            "74.86323",
+            "104.27552",
+            "66.16120",
           ],
           [
-            "131.64884",
-            "63.04575",
+            "126.95494",
+            "64.56052",
           ],
         ]
       `);
@@ -707,8 +707,14 @@ describe("Test Linear Elements", () => {
       // This is the expected midpoint for line with round edge
       // hence hardcoding it so if later some bug is introduced
       // this will fail and we can fix it
-      const firstSegmentMidpoint = pointFrom<GlobalPoint>(47.30521, 57.2734);
-      const lastSegmentMidpoint = pointFrom<GlobalPoint>(83.70877, 40.46424);
+      const firstSegmentMidpoint = pointFrom<GlobalPoint>(
+        55.9697848965255,
+        47.442326230998205,
+      );
+      const lastSegmentMidpoint = pointFrom<GlobalPoint>(
+        76.08587175006699,
+        43.294165939653226,
+      );
       let line: ExcalidrawLinearElement;
 
       beforeEach(() => {
@@ -753,16 +759,16 @@ describe("Test Linear Elements", () => {
                 0,
               ],
               [
-                "77.30521",
-                "87.27340",
+                "85.96978",
+                "77.44233",
               ],
               [
                 70,
                 50,
               ],
               [
-                "113.70877",
-                "70.46424",
+                "106.08587",
+                "73.29417",
               ],
               [
                 40,
@@ -809,12 +815,12 @@ describe("Test Linear Elements", () => {
         expect(newMidPoints).toMatchInlineSnapshot(`
           [
             [
-              "22.32088",
-              "37.43003",
+              "29.28349",
+              "20.91105",
             ],
             [
-              "81.55727",
-              "43.21091",
+              "78.86048",
+              "46.12277",
             ],
           ]
         `);
@@ -898,12 +904,12 @@ describe("Test Linear Elements", () => {
         expect(newMidPoints).toMatchInlineSnapshot(`
           [
             [
-              "51.36383",
-              "54.86323",
+              "54.27552",
+              "46.16120",
             ],
             [
-              "81.64884",
-              "43.04575",
+              "76.95494",
+              "44.56052",
             ],
           ]
         `);
@@ -1065,8 +1071,8 @@ describe("Test Linear Elements", () => {
         );
         expect(position).toMatchInlineSnapshot(`
           {
-            "x": "86.53100",
-            "y": "72.83556",
+            "x": "86.17305",
+            "y": "76.11251",
           }
         `);
       });
@@ -1185,8 +1191,8 @@ describe("Test Linear Elements", () => {
           20,
           105,
           80,
-          "56.68277",
-          "47.27188",
+          "55.45894",
+          45,
         ]
       `);
 
@@ -1196,7 +1202,7 @@ describe("Test Linear Elements", () => {
         .toMatchInlineSnapshot(`
           {
             "height": 130,
-            "width": "368.53316",
+            "width": "366.11716",
           }
         `);
 
@@ -1208,7 +1214,7 @@ describe("Test Linear Elements", () => {
         ),
       ).toMatchInlineSnapshot(`
         {
-          "x": "273.53316",
+          "x": "271.11716",
           "y": 45,
         }
       `);
@@ -1225,10 +1231,10 @@ describe("Test Linear Elements", () => {
         [
           20,
           35,
-          "503.53316",
-          "119.02540",
-          "204.47758",
-          "77.01270",
+          "501.11716",
+          95,
+          "205.45894",
+          "52.50000",
         ]
       `);
     });

packages/excalidraw/actions/actionFinalize.tsx

@@ -27,7 +27,7 @@ import { isInvisiblySmallElement } from "@excalidraw/element";
 
 import { CaptureUpdateAction } from "@excalidraw/element";
 
-import type { GlobalPoint, LocalPoint } from "@excalidraw/math";
+import type { LocalPoint } from "@excalidraw/math";
 import type {
   ExcalidrawElement,
   ExcalidrawLinearElement,
@@ -93,32 +93,40 @@ export const actionFinalize = register<FormData>({
             ? [element.points.length - 1] // New arrow creation
             : appState.selectedLinearElement.selectedPointsIndices;
 
+        const angleLocked = shouldRotateWithDiscreteAngle(event);
+        const effectiveGridSize = event[KEYS.CTRL_OR_CMD]
+          ? null
+          : app.getEffectiveGridSize();
+
         const draggedPoints: PointsPositionUpdates =
           selectedPointsIndices.reduce((map, index) => {
             map.set(index, {
-              point: LinearElementEditor.pointFromAbsoluteCoords(
-                element,
-                pointFrom<GlobalPoint>(
-                  sceneCoords.x - linearElementEditor.pointerOffset.x,
-                  sceneCoords.y - linearElementEditor.pointerOffset.y,
-                ),
-                elementsMap,
-              ),
+              point: angleLocked
+                ? element.points[index]
+                : LinearElementEditor.createPointAt(
+                    element,
+                    elementsMap,
+                    sceneCoords.x - linearElementEditor.pointerOffset.x,
+                    sceneCoords.y - linearElementEditor.pointerOffset.y,
+                    effectiveGridSize,
+                  ),
             });
 
             return map;
           }, new Map()) ?? new Map();
+
         bindOrUnbindBindingElement(
           element,
           draggedPoints,
-          sceneCoords.x - linearElementEditor.pointerOffset.x,
-          sceneCoords.y - linearElementEditor.pointerOffset.y,
+          sceneCoords.x,
+          sceneCoords.y,
           scene,
           appState,
           {
             newArrow,
             altKey: event.altKey,
-            angleLocked: shouldRotateWithDiscreteAngle(event),
+            angleLocked,
+            gridSize: app.getEffectiveGridSize(),
           },
         );
       } else if (isLineElement(element)) {

packages/excalidraw/components/App.tsx

@@ -7263,14 +7263,16 @@ class App extends React.Component<AppProps, AppState> {
       return;
     }
 
-    if (this.state.activeTool.type === "arrow") {
+    // Set suggested binding if we're hovering with an arrow tool
+    // and not dragging out a new element
+    if (this.state.activeTool.type === "arrow" && !this.state.newElement) {
+      const scenePointer = pointFrom<GlobalPoint>(scenePointerX, scenePointerY);
       const hit = getHoveredElementForBinding(
-        pointFrom<GlobalPoint>(scenePointerX, scenePointerY),
+        scenePointer,
         this.scene.getNonDeletedElements(),
         this.scene.getNonDeletedElementsMap(),
         maxBindingDistance_simple(this.state.zoom),
       );
-      const scenePointer = pointFrom<GlobalPoint>(scenePointerX, scenePointerY);
       const elementsMap = this.scene.getNonDeletedElementsMap();
       if (hit && !isPointInElement(scenePointer, hit, elementsMap)) {
         this.setState({

packages/excalidraw/components/canvases/InteractiveCanvas.tsx

@@ -253,6 +253,7 @@ const getRelevantAppStateProps = (
   newElement: appState.newElement,
   isBindingEnabled: appState.isBindingEnabled,
   isMidpointSnappingEnabled: appState.isMidpointSnappingEnabled,
+  gridModeEnabled: appState.gridModeEnabled,
   suggestedBinding: appState.suggestedBinding,
   isRotating: appState.isRotating,
   elementsToHighlight: appState.elementsToHighlight,

packages/excalidraw/renderer/interactiveScene.ts

@@ -17,6 +17,7 @@ import {
   FRAME_STYLE,
   getFeatureFlag,
   invariant,
+  shouldRotateWithDiscreteAngle,
   THEME,
 } from "@excalidraw/common";
 
@@ -229,6 +230,7 @@ const renderBindingHighlightForBindableElement_simple = (
   elementsMap: ElementsMap,
   appState: InteractiveCanvasAppState,
   pointerCoords: GlobalPoint | null,
+  angleLocked = false,
 ) => {
   const enclosingFrame =
     suggestedBinding.element.frameId &&
@@ -415,6 +417,8 @@ const renderBindingHighlightForBindableElement_simple = (
 
   if (
     appState.isMidpointSnappingEnabled &&
+    !appState.gridModeEnabled &&
+    !angleLocked &&
     (isFrameLikeElement(suggestedBinding.element) ||
       isBindableElement(suggestedBinding.element))
   ) {
@@ -807,7 +811,12 @@ const renderBindingHighlightForBindableElement_complex = (
 
     context.restore();
 
-    if (appState.isMidpointSnappingEnabled) {
+    if (
+      appState.isMidpointSnappingEnabled &&
+      !appState.gridModeEnabled &&
+      (!app.lastPointerMoveEvent ||
+        !shouldRotateWithDiscreteAngle(app.lastPointerMoveEvent))
+    ) {
       // Draw midpoint indicators
       context.save();
       context.translate(
@@ -920,12 +929,16 @@ const renderBindingHighlightForBindableElement = (
         app.lastPointerMoveCoords.y,
       )
     : null;
+  const angleLocked =
+    !!app.lastPointerMoveEvent &&
+    shouldRotateWithDiscreteAngle(app.lastPointerMoveEvent);
   renderBindingHighlightForBindableElement_simple(
     context,
     suggestedBinding,
     allElementsMap,
     appState,
     pointerCoords,
+    angleLocked,
   );
   context.restore();
 };

packages/excalidraw/types.ts

@@ -224,6 +224,7 @@ export type InteractiveCanvasAppState = Readonly<
     newElement: AppState["newElement"];
     isBindingEnabled: AppState["isBindingEnabled"];
     isMidpointSnappingEnabled: AppState["isMidpointSnappingEnabled"];
+    gridModeEnabled: AppState["gridModeEnabled"];
     suggestedBinding: AppState["suggestedBinding"];
     isRotating: AppState["isRotating"];
     elementsToHighlight: AppState["elementsToHighlight"];
@@ -845,6 +846,7 @@ export type AppClassProperties = {
   onStateChange: App["onStateChange"];
 
   lastPointerMoveCoords: App["lastPointerMoveCoords"];
+  lastPointerMoveEvent: App["lastPointerMoveEvent"];
   bindModeHandler: App["bindModeHandler"];
 
   setAppState: App["setAppState"];

packages/utils/src/shape.ts

@@ -196,7 +196,7 @@ export const getEllipseShape = <Point extends GlobalPoint | LocalPoint>(
 
 export const getCurvePathOps = (shape: Drawable): Op[] => {
   // NOTE (mtolmacs): Temporary fix for extremely large elements
-  if (!shape || shape.sets.length === 0) {
+  if (!shape) {
     return [];
   }
 
@@ -316,29 +316,26 @@ export const getClosedCurveShape = <Point extends GlobalPoint | LocalPoint>(
     };
   }
 
-  // Prefer the fillPath set
-  const fillPathSet = roughShape.sets.find((s) => s.type === "fillPath");
-  const ops = fillPathSet ? fillPathSet.ops : getCurvePathOps(roughShape);
+  const ops = getCurvePathOps(roughShape);
 
   const points: Point[] = [];
   let odd = false;
   for (const operation of ops) {
     if (operation.op === "move") {
-      if (fillPathSet) {
-        // fillPath is always a single run, no odd/even skipping needed
+      odd = !odd;
+      if (odd) {
         points.push(pointFrom(operation.data[0], operation.data[1]));
-      } else {
-        odd = !odd;
-        if (odd) {
-          points.push(pointFrom(operation.data[0], operation.data[1]));
-        }
       }
     } else if (operation.op === "bcurveTo") {
-      if (fillPathSet || odd) {
+      if (odd) {
         points.push(pointFrom(operation.data[0], operation.data[1]));
         points.push(pointFrom(operation.data[2], operation.data[3]));
         points.push(pointFrom(operation.data[4], operation.data[5]));
       }
+    } else if (operation.op === "lineTo") {
+      if (odd) {
+        points.push(pointFrom(operation.data[0], operation.data[1]));
+      }
     }
   }