floor font on canvas

This reverts commit d75889238d.

.env.development

@@ -23,6 +23,11 @@ REACT_APP_DEV_DISABLE_LIVE_RELOAD=
 
 FAST_REFRESH=false
 
+# MATOMO
+REACT_APP_MATOMO_URL=
+REACT_APP_CDN_MATOMO_TRACKER_URL=
+REACT_APP_MATOMO_SITE_ID=
+
 #Debug flags
 
 # To enable bounding box for text containers

.env.production

@@ -12,6 +12,13 @@ REACT_APP_WS_SERVER_URL=
 REACT_APP_FIREBASE_CONFIG='{"apiKey":"AIzaSyAd15pYlMci_xIp9ko6wkEsDzAAA0Dn0RU","authDomain":"excalidraw-room-persistence.firebaseapp.com","databaseURL":"https://excalidraw-room-persistence.firebaseio.com","projectId":"excalidraw-room-persistence","storageBucket":"excalidraw-room-persistence.appspot.com","messagingSenderId":"654800341332","appId":"1:654800341332:web:4a692de832b55bd57ce0c1"}'
 
 # production-only vars
+# GOOGLE ANALYTICS
 REACT_APP_GOOGLE_ANALYTICS_ID=UA-387204-13
+# MATOMO
+REACT_APP_MATOMO_URL=https://excalidraw.matomo.cloud/
+REACT_APP_CDN_MATOMO_TRACKER_URL=//cdn.matomo.cloud/excalidraw.matomo.cloud/matomo.js
+REACT_APP_MATOMO_SITE_ID=1
+
+
 
 REACT_APP_PLUS_APP=https://app.excalidraw.com

dev-docs/docs/@excalidraw/excalidraw/api/props/ref.mdx

@@ -1,6 +1,19 @@
 # ref
+
 <pre>
-<a href="https://reactjs.org/docs/refs-and-the-dom.html#creating-refs">createRef</a> &#124; <a href="https://reactjs.org/docs/hooks-reference.html#useref">useRef</a> &#124; <a href="https://reactjs.org/docs/refs-and-the-dom.html#callback-refs">callbackRef</a> &#124; <br/>&#123; current: &#123; readyPromise: <a href="https://github.com/excalidraw/excalidraw/blob/master/src/utils.ts#L460">resolvablePromise</a> } }
+  <a href="https://reactjs.org/docs/refs-and-the-dom.html#creating-refs">
+    createRef
+  </a>{" "}
+  &#124;{" "}
+  <a href="https://reactjs.org/docs/hooks-reference.html#useref">useRef</a>{" "}
+  &#124;{" "}
+  <a href="https://reactjs.org/docs/refs-and-the-dom.html#callback-refs">
+    callbackRef
+  </a>{" "}
+  &#124; <br />
+  &#123; current: &#123; readyPromise: <a href="https://github.com/excalidraw/excalidraw/blob/master/src/utils.ts#L460">
+    resolvablePromise
+  </a> } }
 </pre>
 
 You can pass a `ref` when you want to access some excalidraw APIs. We expose the below APIs:
@@ -139,7 +152,9 @@ function App() {
   return (
     <div style={{ height: "500px" }}>
       <p style={{ fontSize: "16px" }}> Click to update the scene</p>
-      <button className="custom-button" onClick={updateScene}>Update Scene</button>
+      <button className="custom-button" onClick={updateScene}>
+        Update Scene
+      </button>
       <Excalidraw ref={(api) => setExcalidrawAPI(api)} />
     </div>
   );
@@ -187,7 +202,8 @@ function App() {
   return (
     <div style={{ height: "500px" }}>
       <p style={{ fontSize: "16px" }}> Click to update the library items</p>
-      <button className="custom-button"
+      <button
+        className="custom-button"
         onClick={() => {
           const libraryItems = [
             {
@@ -205,10 +221,8 @@ function App() {
           ];
           excalidrawAPI.updateLibrary({
             libraryItems,
-            openLibraryMenu: true
-
+            openLibraryMenu: true,
           });
-         
         }}
       >
         Update Library
@@ -250,7 +264,7 @@ Resets the scene. If `resetLoadingState` is passed as true then it will also for
 
 <pre>
   () =>{" "}
-  <a href="https://github.com/excalidraw/excalidraw/blob/master/src/element/types.ts#L114">
+  <a href="https://github.com/excalidraw/excalidraw/blob/master/src/element/types.ts#L115">
     ExcalidrawElement[]
   </a>
 </pre>
@@ -261,7 +275,7 @@ Returns all the elements including the deleted in the scene.
 
 <pre>
   () => NonDeleted&#60;
-  <a href="https://github.com/excalidraw/excalidraw/blob/master/src/element/types.ts#L114">
+  <a href="https://github.com/excalidraw/excalidraw/blob/master/src/element/types.ts#L115">
     ExcalidrawElement
   </a>
   []&#62;
@@ -293,18 +307,31 @@ This is the history API. history.clear() will clear the history.
 ## scrollToContent
 
 <pre>
-  (target?:{" "}
-  <a href="https://github.com/excalidraw/excalidraw/blob/master/src/element/types.ts#L114">
+  (<br />
+  {"  "}
+  target?:{" "}
+  <a href="https://github.com/excalidraw/excalidraw/blob/master/src/element/types.ts#L115">
     ExcalidrawElement
   </a>{" "}
   &#124;{" "}
-  <a href="https://github.com/excalidraw/excalidraw/blob/master/src/element/types.ts#L114">
+  <a href="https://github.com/excalidraw/excalidraw/blob/master/src/element/types.ts#L115">
     ExcalidrawElement
   </a>
-  []) => void
+  [],
+  <br />
+  {"  "}opts?: &#123; fitToContent?: boolean; animate?: boolean; duration?: number
+  &#125;
+  <br />) => void
 </pre>
 
-Scroll the nearest element out of the elements supplied to the center. Defaults to the elements on the scene.
+Scroll the nearest element out of the elements supplied to the center of the viewport. Defaults to the elements on the scene.
+
+| Attribute | type | default | Description |
+| --- | --- | --- | --- |
+| target | <code>ExcalidrawElement &#124; ExcalidrawElement[]</code> | All scene elements | The element(s) to scroll to. |
+| opts.fitToContent | boolean | false | Whether to fit the elements to viewport by automatically changing zoom as needed. |
+| opts.animate | boolean | false | Whether to animate between starting and ending position. Note that for larger scenes the animation may not be smooth due to performance issues. |
+| opts.duration | number | 500 | Duration of the animation if `opts.animate` is `true`. |
 
 ## refresh
 
@@ -323,7 +350,7 @@ For any other cases if the position of excalidraw is updated (example due to scr
 This API can be used to show the toast with custom message.
 
 ```tsx
-({ message: string, closable?:boolean,duration?:number 
+({ message: string, closable?:boolean,duration?:number
   } | null) => void
 ```
 
@@ -358,15 +385,18 @@ This API can be used to get the files present in the scene. It may contain files
 
 This API has the below signature. It sets the `tool` passed in param as the active tool.
 
-
 <pre>
-(tool: <br/>  &#123; type: <a href="https://github.com/excalidraw/excalidraw/blob/master/src/shapes.tsx#L15">SHAPES</a>[number]["value"]&#124; "eraser" &#125; &#124;<br/>  &#123; type: "custom"; customType: string &#125;) => void
+  (tool: <br /> &#123; type:{" "}
+  <a href="https://github.com/excalidraw/excalidraw/blob/master/src/shapes.tsx#L15">
+    SHAPES
+  </a>
+  [number]["value"]&#124; "eraser" &#125; &#124;
+  <br /> &#123; type: "custom"; customType: string &#125;) => void
 </pre>
 
 ## setCursor
 
-This API can be used to customise the mouse cursor on the canvas and has the below signature.   
-It sets the mouse cursor to the cursor passed in param.
+This API can be used to customise the mouse cursor on the canvas and has the below signature. It sets the mouse cursor to the cursor passed in param.
 
 ```tsx
 (cursor: string) => void

public/index.html

@@ -146,8 +146,10 @@
       // setting this so that libraries installation reuses this window tab.
       window.name = "_excalidraw";
     </script>
-    <% if (process.env.REACT_APP_DISABLE_TRACKING !== 'true' &&
-    process.env.REACT_APP_GOOGLE_ANALYTICS_ID) { %>
+    <% if (process.env.REACT_APP_DISABLE_TRACKING !== 'true') { %>
+
+    <!-- LEGACY GOOGLE ANALYTICS -->
+    <% if (process.env.REACT_APP_GOOGLE_ANALYTICS_ID) { %>
     <script
       async
       src="https://www.googletagmanager.com/gtag/js?id=%REACT_APP_GOOGLE_ANALYTICS_ID%"
@@ -160,6 +162,33 @@
       gtag("js", new Date());
       gtag("config", "%REACT_APP_GOOGLE_ANALYTICS_ID%");
     </script>
+    <% } %>
+    <!-- end LEGACY GOOGLE ANALYTICS -->
+
+    <!-- Matomo -->
+    <% if (process.env.REACT_APP_MATOMO_URL &&
+    process.env.REACT_APP_MATOMO_SITE_ID &&
+    process.env.REACT_APP_CDN_MATOMO_TRACKER_URL) { %>
+    <script>
+      var _paq = (window._paq = window._paq || []);
+      /* tracker methods like "setCustomDimension" should be called before "trackPageView" */
+      _paq.push(["trackPageView"]);
+      _paq.push(["enableLinkTracking"]);
+      (function () {
+        var u = "%REACT_APP_MATOMO_URL%";
+        _paq.push(["setTrackerUrl", u + "matomo.php"]);
+        _paq.push(["setSiteId", "%REACT_APP_MATOMO_SITE_ID%"]);
+        var d = document,
+          g = d.createElement("script"),
+          s = d.getElementsByTagName("script")[0];
+        g.async = true;
+        g.src = "%REACT_APP_CDN_MATOMO_TRACKER_URL%";
+        s.parentNode.insertBefore(g, s);
+      })();
+    </script>
+    <% } %>
+    <!-- end Matomo analytics -->
+
     <% } %>
 
     <!-- FIXME: remove this when we update CRA (fix SW caching) -->

src/actions/actionBoundText.tsx

@@ -42,7 +42,7 @@ export const actionUnbindText = register({
     selectedElements.forEach((element) => {
       const boundTextElement = getBoundTextElement(element);
       if (boundTextElement) {
-        const { width, height } = measureText(
+        const { width, height, baseline } = measureText(
           boundTextElement.originalText,
           getFontString(boundTextElement),
           boundTextElement.lineHeight,
@@ -56,6 +56,7 @@ export const actionUnbindText = register({
           containerId: null,
           width,
           height,
+          baseline,
           text: boundTextElement.originalText,
         });
         mutateElement(element, {

src/actions/actionCanvas.tsx

@@ -226,7 +226,7 @@ const zoomValueToFitBoundsOnViewport = (
   return clampedZoomValueToFitElements as NormalizedZoomValue;
 };
 
-const zoomToFitElements = (
+export const zoomToFitElements = (
   elements: readonly ExcalidrawElement[],
   appState: Readonly<AppState>,
   zoomToSelection: boolean,

src/analytics.ts

@@ -1,22 +1,30 @@
-export const trackEvent =
-  typeof process !== "undefined" &&
-  process.env?.REACT_APP_GOOGLE_ANALYTICS_ID &&
-  typeof window !== "undefined" &&
-  window.gtag
-    ? (category: string, action: string, label?: string, value?: number) => {
-        try {
-          window.gtag("event", action, {
-            event_category: category,
-            event_label: label,
-            value,
-          });
-        } catch (error) {
-          console.error("error logging to ga", error);
-        }
-      }
-    : typeof process !== "undefined" && process.env?.JEST_WORKER_ID
-    ? (category: string, action: string, label?: string, value?: number) => {}
-    : (category: string, action: string, label?: string, value?: number) => {
-        // Uncomment the next line to track locally
-        // console.log("Track Event", { category, action, label, value });
-      };
+export const trackEvent = (
+  category: string,
+  action: string,
+  label?: string,
+  value?: number,
+) => {
+  try {
+    // Uncomment the next line to track locally
+    // console.log("Track Event", { category, action, label, value });
+
+    if (typeof window === "undefined" || process.env.JEST_WORKER_ID) {
+      return;
+    }
+
+    if (process.env.REACT_APP_GOOGLE_ANALYTICS_ID && window.gtag) {
+      window.gtag("event", action, {
+        event_category: category,
+        event_label: label,
+        value,
+      });
+    }
+
+    // MATOMO event tracking _paq must be same as the one in index.html
+    if (window._paq) {
+      window._paq.push(["trackEvent", category, action, label, value]);
+    }
+  } catch (error) {
+    console.error("error during analytics", error);
+  }
+};

src/components/App.tsx

@@ -229,6 +229,7 @@ import {
   updateActiveTool,
   getShortcutKey,
   isTransparent,
+  easeToValuesRAF,
 } from "../utils";
 import {
   ContextMenu,
@@ -284,7 +285,10 @@ import {
 import { shouldShowBoundingBox } from "../element/transformHandles";
 import { Fonts } from "../scene/Fonts";
 import { actionPaste } from "../actions/actionClipboard";
-import { actionToggleHandTool } from "../actions/actionCanvas";
+import {
+  actionToggleHandTool,
+  zoomToFitElements,
+} from "../actions/actionCanvas";
 import { jotaiStore } from "../jotai";
 import { activeConfirmDialogAtom } from "./ActiveConfirmDialog";
 import { actionCreateContainerFromText } from "../actions/actionBoundText";
@@ -1843,18 +1847,89 @@ class App extends React.Component<AppProps, AppState> {
     this.actionManager.executeAction(actionToggleHandTool);
   };
 
+  /**
+   * Zooms on canvas viewport center
+   */
+  zoomCanvas = (
+    /** decimal fraction between 0.1 (10% zoom) and 30 (3000% zoom) */
+    value: number,
+  ) => {
+    this.setState({
+      ...getStateForZoom(
+        {
+          viewportX: this.state.width / 2 + this.state.offsetLeft,
+          viewportY: this.state.height / 2 + this.state.offsetTop,
+          nextZoom: getNormalizedZoom(value),
+        },
+        this.state,
+      ),
+    });
+  };
+
+  private cancelInProgresAnimation: (() => void) | null = null;
+
   scrollToContent = (
     target:
       | ExcalidrawElement
       | readonly ExcalidrawElement[] = this.scene.getNonDeletedElements(),
+    opts?: { fitToContent?: boolean; animate?: boolean; duration?: number },
   ) => {
-    this.setState({
-      ...calculateScrollCenter(
-        Array.isArray(target) ? target : [target],
-        this.state,
-        this.canvas,
-      ),
-    });
+    this.cancelInProgresAnimation?.();
+
+    // convert provided target into ExcalidrawElement[] if necessary
+    const targets = Array.isArray(target) ? target : [target];
+
+    let zoom = this.state.zoom;
+    let scrollX = this.state.scrollX;
+    let scrollY = this.state.scrollY;
+
+    if (opts?.fitToContent) {
+      // compute an appropriate viewport location (scroll X, Y) and zoom level
+      // that fit the target elements on the scene
+      const { appState } = zoomToFitElements(targets, this.state, false);
+      zoom = appState.zoom;
+      scrollX = appState.scrollX;
+      scrollY = appState.scrollY;
+    } else {
+      // compute only the viewport location, without any zoom adjustment
+      const scroll = calculateScrollCenter(targets, this.state, this.canvas);
+      scrollX = scroll.scrollX;
+      scrollY = scroll.scrollY;
+    }
+
+    // when animating, we use RequestAnimationFrame to prevent the animation
+    // from slowing down other processes
+    if (opts?.animate) {
+      const origScrollX = this.state.scrollX;
+      const origScrollY = this.state.scrollY;
+
+      // zoom animation could become problematic on scenes with large number
+      // of elements, setting it to its final value to improve user experience.
+      //
+      // using zoomCanvas() to zoom on current viewport center
+      this.zoomCanvas(zoom.value);
+
+      const cancel = easeToValuesRAF(
+        [origScrollX, origScrollY],
+        [scrollX, scrollY],
+        (scrollX, scrollY) => this.setState({ scrollX, scrollY }),
+        { duration: opts?.duration ?? 500 },
+      );
+      this.cancelInProgresAnimation = () => {
+        cancel();
+        this.cancelInProgresAnimation = null;
+      };
+    } else {
+      this.setState({ scrollX, scrollY, zoom });
+    }
+  };
+
+  /** use when changing scrollX/scrollY/zoom based on user interaction */
+  private translateCanvas: React.Component<any, AppState>["setState"] = (
+    state,
+  ) => {
+    this.cancelInProgresAnimation?.();
+    this.setState(state);
   };
 
   setToast = (
@@ -2055,9 +2130,13 @@ class App extends React.Component<AppProps, AppState> {
           offset = -offset;
         }
         if (event.shiftKey) {
-          this.setState((state) => ({ scrollX: state.scrollX + offset }));
+          this.translateCanvas((state) => ({
+            scrollX: state.scrollX + offset,
+          }));
         } else {
-          this.setState((state) => ({ scrollY: state.scrollY + offset }));
+          this.translateCanvas((state) => ({
+            scrollY: state.scrollY + offset,
+          }));
         }
       }
 
@@ -2938,12 +3017,12 @@ class App extends React.Component<AppProps, AppState> {
           state,
         );
 
-        return {
+        this.translateCanvas({
           zoom: zoomState.zoom,
           scrollX: zoomState.scrollX + deltaX / nextZoom,
           scrollY: zoomState.scrollY + deltaY / nextZoom,
           shouldCacheIgnoreZoom: true,
-        };
+        });
       });
       this.resetShouldCacheIgnoreZoomDebounced();
     } else {
@@ -3719,7 +3798,7 @@ class App extends React.Component<AppProps, AppState> {
         window.addEventListener(EVENT.POINTER_UP, enableNextPaste);
       }
 
-      this.setState({
+      this.translateCanvas({
         scrollX: this.state.scrollX - deltaX / this.state.zoom.value,
         scrollY: this.state.scrollY - deltaY / this.state.zoom.value,
       });
@@ -4865,7 +4944,7 @@ class App extends React.Component<AppProps, AppState> {
     if (pointerDownState.scrollbars.isOverHorizontal) {
       const x = event.clientX;
       const dx = x - pointerDownState.lastCoords.x;
-      this.setState({
+      this.translateCanvas({
         scrollX: this.state.scrollX - dx / this.state.zoom.value,
       });
       pointerDownState.lastCoords.x = x;
@@ -4875,7 +4954,7 @@ class App extends React.Component<AppProps, AppState> {
     if (pointerDownState.scrollbars.isOverVertical) {
       const y = event.clientY;
       const dy = y - pointerDownState.lastCoords.y;
-      this.setState({
+      this.translateCanvas({
         scrollY: this.state.scrollY - dy / this.state.zoom.value,
       });
       pointerDownState.lastCoords.y = y;
@@ -6304,7 +6383,7 @@ class App extends React.Component<AppProps, AppState> {
         // reduced amplification for small deltas (small movements on a trackpad)
         Math.min(1, absDelta / 20);
 
-      this.setState((state) => ({
+      this.translateCanvas((state) => ({
         ...getStateForZoom(
           {
             viewportX: cursorX,
@@ -6321,14 +6400,14 @@ class App extends React.Component<AppProps, AppState> {
 
     // scroll horizontally when shift pressed
     if (event.shiftKey) {
-      this.setState(({ zoom, scrollX }) => ({
+      this.translateCanvas(({ zoom, scrollX }) => ({
         // on Mac, shift+wheel tends to result in deltaX
         scrollX: scrollX - (deltaY || deltaX) / zoom.value,
       }));
       return;
     }
 
-    this.setState(({ zoom, scrollX, scrollY }) => ({
+    this.translateCanvas(({ zoom, scrollX, scrollY }) => ({
       scrollX: scrollX - deltaX / zoom.value,
       scrollY: scrollY - deltaY / zoom.value,
     }));

src/data/restore.ts

@@ -31,11 +31,15 @@ import {
 import { getDefaultAppState } from "../appState";
 import { LinearElementEditor } from "../element/linearElementEditor";
 import { bumpVersion } from "../element/mutateElement";
-import { getUpdatedTimestamp, updateActiveTool } from "../utils";
+import { getFontString, getUpdatedTimestamp, updateActiveTool } from "../utils";
 import { arrayToMap } from "../utils";
 import oc from "open-color";
 import { MarkOptional, Mutable } from "../utility-types";
-import { detectLineHeight, getDefaultLineHeight } from "../element/textElement";
+import {
+  detectLineHeight,
+  getDefaultLineHeight,
+  getDOMMetrics,
+} from "../element/textElement";
 
 type RestoredAppState = Omit<
   AppState,
@@ -171,6 +175,24 @@ const restoreElement = (
       }
       const text = element.text ?? "";
 
+      // line-height might not be specified either when creating elements
+      // programmatically, or when importing old diagrams.
+      // For the latter we want to detect the original line height which
+      // will likely differ from our per-font fixed line height we now use,
+      // to maintain backward compatibility.
+      const lineHeight =
+        element.lineHeight ||
+        (element.height
+          ? // detect line-height from current element height and font-size
+            detectLineHeight(element)
+          : // no element height likely means programmatic use, so default
+            // to a fixed line height
+            getDefaultLineHeight(element.fontFamily));
+      const { baseline } = getDOMMetrics(
+        element.text,
+        getFontString(element),
+        lineHeight,
+      );
       element = restoreElementWithProperties(element, {
         fontSize,
         fontFamily,
@@ -179,19 +201,9 @@ const restoreElement = (
         verticalAlign: element.verticalAlign || DEFAULT_VERTICAL_ALIGN,
         containerId: element.containerId ?? null,
         originalText: element.originalText || text,
-        // line-height might not be specified either when creating elements
-        // programmatically, or when importing old diagrams.
-        // For the latter we want to detect the original line height which
-        // will likely differ from our per-font fixed line height we now use,
-        // to maintain backward compatibility.
-        lineHeight:
-          element.lineHeight ||
-          (element.height
-            ? // detect line-height from current element height and font-size
-              detectLineHeight(element)
-            : // no element height likely means programmatic use, so default
-              // to a fixed line height
-              getDefaultLineHeight(element.fontFamily)),
+
+        lineHeight,
+        baseline,
       });
 
       if (refreshDimensions) {
@@ -495,7 +507,9 @@ export const restoreAppState = (
         ? {
             value: appState.zoom as NormalizedZoomValue,
           }
-        : appState.zoom || defaultAppState.zoom,
+        : appState.zoom?.value
+        ? appState.zoom
+        : defaultAppState.zoom,
     // when sidebar docked and user left it open in last session,
     // keep it open. If not docked, keep it closed irrespective of last state.
     openSidebar:

src/element/newElement.ts

@@ -145,6 +145,7 @@ export const newTextElement = (
   const text = normalizeText(opts.text);
   const metrics = measureText(text, getFontString(opts), lineHeight);
   const offsets = getTextElementPositionOffsets(opts, metrics);
+
   const textElement = newElementWith(
     {
       ..._newElementBase<ExcalidrawTextElement>("text", opts),
@@ -157,6 +158,7 @@ export const newTextElement = (
       y: opts.y - offsets.y,
       width: metrics.width,
       height: metrics.height,
+      baseline: metrics.baseline,
       containerId: opts.containerId || null,
       originalText: text,
       lineHeight,
@@ -174,14 +176,15 @@ const getAdjustedDimensions = (
   y: number;
   width: number;
   height: number;
+  baseline: number;
 } => {
   const container = getContainerElement(element);
 
-  const { width: nextWidth, height: nextHeight } = measureText(
-    nextText,
-    getFontString(element),
-    element.lineHeight,
-  );
+  const {
+    width: nextWidth,
+    height: nextHeight,
+    baseline: nextBaseline,
+  } = measureText(nextText, getFontString(element), element.lineHeight);
   const { textAlign, verticalAlign } = element;
   let x: number;
   let y: number;
@@ -256,6 +259,7 @@ const getAdjustedDimensions = (
   return {
     width: nextWidth,
     height: nextHeight,
+    baseline: nextBaseline,
     x: Number.isFinite(x) ? x : element.x,
     y: Number.isFinite(y) ? y : element.y,
   };

src/element/resizeElements.ts

@@ -46,6 +46,8 @@ import {
   handleBindTextResize,
   getMaxContainerWidth,
   getApproxMinLineHeight,
+  measureText,
+  getMaxContainerHeight,
 } from "./textElement";
 
 export const normalizeAngle = (angle: number): number => {
@@ -193,7 +195,8 @@ const MIN_FONT_SIZE = 1;
 const measureFontSizeFromWidth = (
   element: NonDeleted<ExcalidrawTextElement>,
   nextWidth: number,
-): number | null => {
+  nextHeight: number,
+): { size: number; baseline: number } | null => {
   // We only use width to scale font on resize
   let width = element.width;
 
@@ -208,8 +211,15 @@ const measureFontSizeFromWidth = (
   if (nextFontSize < MIN_FONT_SIZE) {
     return null;
   }
-
-  return nextFontSize;
+  const metrics = measureText(
+    element.text,
+    getFontString({ fontSize: nextFontSize, fontFamily: element.fontFamily }),
+    element.lineHeight,
+  );
+  return {
+    size: nextFontSize,
+    baseline: metrics.baseline + (nextHeight - metrics.height),
+  };
 };
 
 const getSidesForTransformHandle = (
@@ -280,8 +290,8 @@ const resizeSingleTextElement = (
   if (scale > 0) {
     const nextWidth = element.width * scale;
     const nextHeight = element.height * scale;
-    const nextFontSize = measureFontSizeFromWidth(element, nextWidth);
-    if (nextFontSize === null) {
+    const metrics = measureFontSizeFromWidth(element, nextWidth, nextHeight);
+    if (metrics === null) {
       return;
     }
     const [nextX1, nextY1, nextX2, nextY2] = getResizedElementAbsoluteCoords(
@@ -305,9 +315,10 @@ const resizeSingleTextElement = (
       deltaY2,
     );
     mutateElement(element, {
-      fontSize: nextFontSize,
+      fontSize: metrics.size,
       width: nextWidth,
       height: nextHeight,
+      baseline: metrics.baseline,
       x: nextElementX,
       y: nextElementY,
     });
@@ -360,7 +371,7 @@ export const resizeSingleElement = (
   let scaleX = atStartBoundsWidth / boundsCurrentWidth;
   let scaleY = atStartBoundsHeight / boundsCurrentHeight;
 
-  let boundTextFontSize: number | null = null;
+  let boundTextFont: { fontSize?: number; baseline?: number } = {};
   const boundTextElement = getBoundTextElement(element);
 
   if (transformHandleDirection.includes("e")) {
@@ -410,7 +421,10 @@ export const resizeSingleElement = (
       boundTextElement.id,
     ) as typeof boundTextElement | undefined;
     if (stateOfBoundTextElementAtResize) {
-      boundTextFontSize = stateOfBoundTextElementAtResize.fontSize;
+      boundTextFont = {
+        fontSize: stateOfBoundTextElementAtResize.fontSize,
+        baseline: stateOfBoundTextElementAtResize.baseline,
+      };
     }
     if (shouldMaintainAspectRatio) {
       const updatedElement = {
@@ -419,14 +433,18 @@ export const resizeSingleElement = (
         height: eleNewHeight,
       };
 
-      const nextFontSize = measureFontSizeFromWidth(
+      const nextFont = measureFontSizeFromWidth(
         boundTextElement,
         getMaxContainerWidth(updatedElement),
+        getMaxContainerHeight(updatedElement),
       );
-      if (nextFontSize === null) {
+      if (nextFont === null) {
         return;
       }
-      boundTextFontSize = nextFontSize;
+      boundTextFont = {
+        fontSize: nextFont.size,
+        baseline: nextFont.baseline,
+      };
     } else {
       const minWidth = getApproxMinLineWidth(
         getFontString(boundTextElement),
@@ -568,9 +586,10 @@ export const resizeSingleElement = (
     });
 
     mutateElement(element, resizedElement);
-    if (boundTextElement && boundTextFontSize != null) {
+    if (boundTextElement && boundTextFont != null) {
       mutateElement(boundTextElement, {
-        fontSize: boundTextFontSize,
+        fontSize: boundTextFont.fontSize,
+        baseline: boundTextFont.baseline,
       });
     }
     handleBindTextResize(element, transformHandleDirection);
@@ -677,6 +696,7 @@ const resizeMultipleElements = (
       y: number;
       points?: Point[];
       fontSize?: number;
+      baseline?: number;
     } = {
       width,
       height,
@@ -685,7 +705,7 @@ const resizeMultipleElements = (
       ...rescaledPoints,
     };
 
-    let boundTextUpdates: { fontSize: number } | null = null;
+    let boundTextUpdates: { fontSize: number; baseline: number } | null = null;
 
     const boundTextElement = getBoundTextElement(element.latest);
 
@@ -695,24 +715,29 @@ const resizeMultipleElements = (
         width,
         height,
       };
-      const fontSize = measureFontSizeFromWidth(
+      const metrics = measureFontSizeFromWidth(
         boundTextElement ?? (element.orig as ExcalidrawTextElement),
         boundTextElement
           ? getMaxContainerWidth(updatedElement)
           : updatedElement.width,
+        boundTextElement
+          ? getMaxContainerHeight(updatedElement)
+          : updatedElement.height,
       );
 
-      if (!fontSize) {
+      if (!metrics) {
         return;
       }
 
       if (isTextElement(element.orig)) {
-        update.fontSize = fontSize;
+        update.fontSize = metrics.size;
+        update.baseline = metrics.baseline;
       }
 
       if (boundTextElement) {
         boundTextUpdates = {
-          fontSize,
+          fontSize: metrics.size,
+          baseline: metrics.baseline,
         };
       }
     }

src/element/textElement.test.ts

@@ -332,6 +332,12 @@ describe("Test getDefaultLineHeight", () => {
     //@ts-ignore
     expect(getDefaultLineHeight()).toBe(1.25);
   });
+
+  it("should return line height using default font family for unknown font", () => {
+    const UNKNOWN_FONT = 5;
+    expect(getDefaultLineHeight(UNKNOWN_FONT)).toBe(1.25);
+  });
+
   it("should return correct line height", () => {
     expect(getDefaultLineHeight(FONT_FAMILY.Cascadia)).toBe(1.2);
   });

src/element/textElement.ts

@@ -14,6 +14,7 @@ import {
   DEFAULT_FONT_FAMILY,
   DEFAULT_FONT_SIZE,
   FONT_FAMILY,
+  isSafari,
   TEXT_ALIGN,
   VERTICAL_ALIGN,
 } from "../constants";
@@ -58,6 +59,7 @@ export const redrawTextBoundingBox = (
     text: textElement.text,
     width: textElement.width,
     height: textElement.height,
+    baseline: textElement.baseline,
   };
 
   boundTextUpdates.text = textElement.text;
@@ -78,6 +80,7 @@ export const redrawTextBoundingBox = (
 
   boundTextUpdates.width = metrics.width;
   boundTextUpdates.height = metrics.height;
+  boundTextUpdates.baseline = metrics.baseline;
 
   if (container) {
     if (isArrowElement(container)) {
@@ -183,6 +186,7 @@ export const handleBindTextResize = (
     const maxWidth = getMaxContainerWidth(container);
     const maxHeight = getMaxContainerHeight(container);
     let containerHeight = containerDims.height;
+    let nextBaseLine = textElement.baseline;
     if (transformHandleType !== "n" && transformHandleType !== "s") {
       if (text) {
         text = wrapText(
@@ -191,13 +195,14 @@ export const handleBindTextResize = (
           maxWidth,
         );
       }
-      const dimensions = measureText(
+      const metrics = measureText(
         text,
         getFontString(textElement),
         textElement.lineHeight,
       );
-      nextHeight = dimensions.height;
-      nextWidth = dimensions.width;
+      nextHeight = metrics.height;
+      nextWidth = metrics.width;
+      nextBaseLine = metrics.baseline;
     }
     // increase height in case text element height exceeds
     if (nextHeight > maxHeight) {
@@ -225,6 +230,7 @@ export const handleBindTextResize = (
       text,
       width: nextWidth,
       height: nextHeight,
+      baseline: nextBaseLine,
     });
 
     if (!isArrowElement(container)) {
@@ -285,8 +291,60 @@ export const measureText = (
   const fontSize = parseFloat(font);
   const height = getTextHeight(text, fontSize, lineHeight);
   const width = getTextWidth(text, font);
+  const { baseline } = getDOMMetrics(text, font, lineHeight);
+  return { width, height, baseline };
+};
 
-  return { width, height };
+export const getDOMMetrics = (
+  text: string,
+  font: FontString,
+  lineHeight: ExcalidrawTextElement["lineHeight"],
+  wrapInContainer?: boolean,
+) => {
+  const container = document.createElement("div");
+  container.style.position = "absolute";
+  container.style.whiteSpace = "pre";
+  container.style.font = font;
+  container.style.minHeight = "1em";
+  if (wrapInContainer) {
+    container.style.overflow = "hidden";
+    container.style.wordBreak = "break-word";
+    container.style.whiteSpace = "pre-wrap";
+  }
+
+  container.style.lineHeight = String(lineHeight);
+  const canvasHeight = getTextHeight(text, parseFloat(font), lineHeight);
+
+  container.innerText = text;
+
+  // Baseline is important for positioning text on canvas
+  document.body.appendChild(container);
+
+  const span = document.createElement("span");
+  span.style.display = "inline-block";
+  span.style.overflow = "hidden";
+  span.style.width = "1px";
+  span.style.height = "1px";
+  container.appendChild(span);
+  let baseline = span.offsetTop + span.offsetHeight;
+  const height = container.offsetHeight;
+
+  if (isSafari) {
+    // In Safari sometimes DOM height could be less than canvas height due to
+    // which text could go out of the bounding box hence shifting the baseline
+    // to make sure text is rendered correctly
+    if (canvasHeight > height) {
+      baseline += canvasHeight - height;
+    }
+    // In Safari sometimes DOM height could be more than canvas height due to
+    // which text could go out of the bounding box hence shifting the baseline
+    // to make sure text is rendered correctly
+    if (height > canvasHeight) {
+      baseline -= height - canvasHeight;
+    }
+  }
+  document.body.removeChild(container);
+  return { baseline, height };
 };
 
 /**
@@ -308,7 +366,9 @@ export const getLineHeightInPx = (
   fontSize: ExcalidrawTextElement["fontSize"],
   lineHeight: ExcalidrawTextElement["lineHeight"],
 ) => {
-  return fontSize * lineHeight;
+  const res = fontSize * lineHeight;
+
+  return res;
 };
 
 // FIXME rename to getApproxMinContainerHeight
@@ -887,7 +947,7 @@ const DEFAULT_LINE_HEIGHT = {
 };
 
 export const getDefaultLineHeight = (fontFamily: FontFamilyValues) => {
-  if (fontFamily) {
+  if (fontFamily in DEFAULT_LINE_HEIGHT) {
     return DEFAULT_LINE_HEIGHT[fontFamily];
   }
   return DEFAULT_LINE_HEIGHT[DEFAULT_FONT_FAMILY];

src/element/textWysiwyg.test.tsx

@@ -526,6 +526,44 @@ describe("textWysiwyg", () => {
       ]);
     });
 
+    it("should compute the container height correctly and not throw error when height is updated while editing the text", async () => {
+      const diamond = API.createElement({
+        type: "diamond",
+        x: 10,
+        y: 20,
+        width: 90,
+        height: 75,
+      });
+      h.elements = [diamond];
+
+      expect(h.elements.length).toBe(1);
+      expect(h.elements[0].id).toBe(diamond.id);
+
+      API.setSelectedElements([diamond]);
+      Keyboard.keyPress(KEYS.ENTER);
+
+      const editor = document.querySelector(
+        ".excalidraw-textEditorContainer > textarea",
+      ) as HTMLTextAreaElement;
+
+      await new Promise((r) => setTimeout(r, 0));
+      const value = new Array(1000).fill("1").join("\n");
+
+      // Pasting large text to simulate height increase
+      expect(() =>
+        fireEvent.input(editor, { target: { value } }),
+      ).not.toThrow();
+
+      expect(diamond.height).toBe(50020);
+
+      // Clearing text to simulate height decrease
+      expect(() =>
+        fireEvent.input(editor, { target: { value: "" } }),
+      ).not.toThrow();
+
+      expect(diamond.height).toBe(70);
+    });
+
     it("should bind text to container when double clicked on center of transparent container", async () => {
       const rectangle = API.createElement({
         type: "rectangle",
@@ -1181,9 +1219,7 @@ describe("textWysiwyg", () => {
       expect(
         (h.elements[1] as ExcalidrawTextElementWithContainer).fontSize,
       ).toEqual(36);
-      expect(getOriginalContainerHeightFromCache(rectangle.id)).toBe(
-        96.39999999999999,
-      );
+      expect(getOriginalContainerHeightFromCache(rectangle.id)).toBe(97);
     });
 
     it("should update line height when font family updated", async () => {

src/element/textWysiwyg.tsx

@@ -11,7 +11,7 @@ import {
   isBoundToContainer,
   isTextElement,
 } from "./typeChecks";
-import { CLASSES, VERTICAL_ALIGN } from "../constants";
+import { CLASSES, isSafari, VERTICAL_ALIGN } from "../constants";
 import {
   ExcalidrawElement,
   ExcalidrawLinearElement,
@@ -34,6 +34,10 @@ import {
   wrapText,
   getMaxContainerHeight,
   getMaxContainerWidth,
+  computeContainerDimensionForBoundText,
+  getDOMMetrics,
+  splitIntoLines,
+  detectLineHeight,
 } from "./textElement";
 import {
   actionDecreaseFontSize,
@@ -208,11 +212,12 @@ export const textWysiwyg = ({
 
         // autogrow container height if text exceeds
         if (!isArrowElement(container) && textElementHeight > maxHeight) {
-          const diff = Math.min(
-            textElementHeight - maxHeight,
-            element.lineHeight,
+          const targetContainerHeight = computeContainerDimensionForBoundText(
+            textElementHeight,
+            container.type,
           );
-          mutateElement(container, { height: containerDims.height + diff });
+
+          mutateElement(container, { height: targetContainerHeight });
           return;
         } else if (
           // autoshrink container height until original container height
@@ -221,11 +226,11 @@ export const textWysiwyg = ({
           containerDims.height > originalContainerData.height &&
           textElementHeight < maxHeight
         ) {
-          const diff = Math.min(
-            maxHeight - textElementHeight,
-            element.lineHeight,
+          const targetContainerHeight = computeContainerDimensionForBoundText(
+            textElementHeight,
+            container.type,
           );
-          mutateElement(container, { height: containerDims.height - diff });
+          mutateElement(container, { height: targetContainerHeight });
         }
         // Start pushing text upward until a diff of 30px (padding)
         // is reached
@@ -269,25 +274,38 @@ export const textWysiwyg = ({
       } else {
         textElementWidth += 0.5;
       }
+      const { height: domHeight } = getDOMMetrics(
+        updatedTextElement.text,
+        getFontString(updatedTextElement),
+        updatedTextElement.lineHeight,
+      );
+
+      let lineHeight = element.lineHeight;
+      const fontSize = Math.floor(updatedTextElement.fontSize);
+
+      if (isSafari) {
+        //@ts-ignore
+        lineHeight =
+          updatedTextElement.height /
+          splitIntoLines(updatedTextElement.text).length /
+          fontSize;
+      }
+
       // Make sure text editor height doesn't go beyond viewport
       const editorMaxHeight =
         (appState.height - viewportY) / appState.zoom.value;
       Object.assign(editable.style, {
-        font: getFontString(updatedTextElement),
+        font: getFontString({
+          fontSize,
+          fontFamily: updatedTextElement.fontFamily,
+        }),
         // must be defined *after* font ¯\_(ツ)_/¯
-        lineHeight: element.lineHeight,
+        lineHeight,
         width: `${textElementWidth}px`,
         height: `${textElementHeight}px`,
         left: `${viewportX}px`,
         top: `${viewportY}px`,
-        transform: getTransform(
-          textElementWidth,
-          textElementHeight,
-          getTextElementAngle(updatedTextElement),
-          appState,
-          maxWidth,
-          editorMaxHeight,
-        ),
+        transform: `scale(${updatedTextElement.fontSize / fontSize})`,
         textAlign,
         verticalAlign,
         color: updatedTextElement.strokeColor,
@@ -295,6 +313,7 @@ export const textWysiwyg = ({
         filter: "var(--theme-filter)",
         maxHeight: `${editorMaxHeight}px`,
       });
+      editable.scrollTop = 0;
       // For some reason updating font attribute doesn't set font family
       // hence updating font family explicitly for test environment
       if (isTestEnv()) {

src/element/types.ts

@@ -131,6 +131,7 @@ export type ExcalidrawTextElement = _ExcalidrawElementBase &
     fontSize: number;
     fontFamily: FontFamilyValues;
     text: string;
+    baseline: number;
     textAlign: TextAlign;
     verticalAlign: VerticalAlign;
     containerId: ExcalidrawGenericElement["id"] | null;

src/global.d.ts

@@ -18,6 +18,8 @@ interface Window {
   EXCALIDRAW_EXPORT_SOURCE: string;
   EXCALIDRAW_THROTTLE_RENDER: boolean | undefined;
   gtag: Function;
+  _paq: any[];
+  _mtm: any[];
 }
 
 interface CanvasRenderingContext2D {

src/packages/excalidraw/CHANGELOG.md

@@ -15,6 +15,8 @@ Please add the latest change on the top under the correct section.
 
 ### Features
 
+- [`ExcalidrawAPI.scrolToContent`](https://docs.excalidraw.com/docs/@excalidraw/excalidraw/api/props/ref#scrolltocontent) has new opts object allowing you to fit viewport to content, and animate the scrolling. [#6319](https://github.com/excalidraw/excalidraw/pull/6319)
+
 - Expose `useI18n()` hook return an object containing `t()` i18n helper and current `langCode`. You can use this in components you render as `<Excalidraw>` children to render any of our i18n locale strings. [#6224](https://github.com/excalidraw/excalidraw/pull/6224)
 
 - [`restoreElements`](https://docs.excalidraw.com/docs/@excalidraw/excalidraw/api/utils/restore#restoreelements) API now takes an optional parameter `opts` which currently supports the below attributes

src/renderer/renderElement.ts

@@ -200,7 +200,6 @@ const drawImagePlaceholder = (
     size,
   );
 };
-
 const drawElementOnCanvas = (
   element: NonDeletedExcalidrawElement,
   rc: RoughCanvas,
@@ -273,7 +272,10 @@ const drawElementOnCanvas = (
         }
         context.canvas.setAttribute("dir", rtl ? "rtl" : "ltr");
         context.save();
-        context.font = getFontString(element);
+        context.font = getFontString({
+          ...element,
+          fontSize: Math.floor(element.fontSize),
+        });
         context.fillStyle = element.strokeColor;
         context.textAlign = element.textAlign as CanvasTextAlign;
 
@@ -286,18 +288,16 @@ const drawElementOnCanvas = (
             : element.textAlign === "right"
             ? element.width
             : 0;
-        context.textBaseline = "bottom";
-
         const lineHeightPx = getLineHeightInPx(
           element.fontSize,
           element.lineHeight,
         );
-
+        const verticalOffset = element.height - element.baseline;
         for (let index = 0; index < lines.length; index++) {
           context.fillText(
             lines[index],
             horizontalOffset,
-            (index + 1) * lineHeightPx,
+            (index + 1) * lineHeightPx - verticalOffset,
           );
         }
         context.restore();

src/tests/data/__snapshots__/restore.test.ts.snap

@@ -282,6 +282,7 @@ exports[`restoreElements should restore text element correctly passing value for
 Object {
   "angle": 0,
   "backgroundColor": "transparent",
+  "baseline": 0,
   "boundElements": Array [],
   "containerId": null,
   "fillStyle": "hachure",
@@ -321,6 +322,7 @@ exports[`restoreElements should restore text element correctly with unknown font
 Object {
   "angle": 0,
   "backgroundColor": "transparent",
+  "baseline": 0,
   "boundElements": Array [],
   "containerId": null,
   "fillStyle": "hachure",

src/tests/fitToContent.test.tsx

@@ -0,0 +1,189 @@
+import { render } from "./test-utils";
+import { API } from "./helpers/api";
+
+import ExcalidrawApp from "../excalidraw-app";
+
+const { h } = window;
+
+describe("fitToContent", () => {
+  it("should zoom to fit the selected element", async () => {
+    await render(<ExcalidrawApp />);
+
+    h.state.width = 10;
+    h.state.height = 10;
+
+    const rectElement = API.createElement({
+      width: 50,
+      height: 100,
+      x: 50,
+      y: 100,
+    });
+
+    expect(h.state.zoom.value).toBe(1);
+
+    h.app.scrollToContent(rectElement, { fitToContent: true });
+
+    // element is 10x taller than the viewport size,
+    // zoom should be at least 1/10
+    expect(h.state.zoom.value).toBeLessThanOrEqual(0.1);
+  });
+
+  it("should zoom to fit multiple elements", async () => {
+    await render(<ExcalidrawApp />);
+
+    const topLeft = API.createElement({
+      width: 20,
+      height: 20,
+      x: 0,
+      y: 0,
+    });
+
+    const bottomRight = API.createElement({
+      width: 20,
+      height: 20,
+      x: 80,
+      y: 80,
+    });
+
+    h.state.width = 10;
+    h.state.height = 10;
+
+    expect(h.state.zoom.value).toBe(1);
+
+    h.app.scrollToContent([topLeft, bottomRight], {
+      fitToContent: true,
+    });
+
+    // elements take 100x100, which is 10x bigger than the viewport size,
+    // zoom should be at least 1/10
+    expect(h.state.zoom.value).toBeLessThanOrEqual(0.1);
+  });
+
+  it("should scroll the viewport to the selected element", async () => {
+    await render(<ExcalidrawApp />);
+
+    h.state.width = 10;
+    h.state.height = 10;
+
+    const rectElement = API.createElement({
+      width: 100,
+      height: 100,
+      x: 100,
+      y: 100,
+    });
+
+    expect(h.state.zoom.value).toBe(1);
+    expect(h.state.scrollX).toBe(0);
+    expect(h.state.scrollY).toBe(0);
+
+    h.app.scrollToContent(rectElement);
+
+    // zoom level should stay the same
+    expect(h.state.zoom.value).toBe(1);
+
+    // state should reflect some scrolling
+    expect(h.state.scrollX).not.toBe(0);
+    expect(h.state.scrollY).not.toBe(0);
+  });
+});
+
+const waitForNextAnimationFrame = () => {
+  return new Promise((resolve) => {
+    requestAnimationFrame(() => {
+      requestAnimationFrame(resolve);
+    });
+  });
+};
+
+describe("fitToContent animated", () => {
+  beforeEach(() => {
+    jest.spyOn(window, "requestAnimationFrame");
+  });
+
+  afterEach(() => {
+    jest.restoreAllMocks();
+  });
+
+  it("should ease scroll the viewport to the selected element", async () => {
+    await render(<ExcalidrawApp />);
+
+    h.state.width = 10;
+    h.state.height = 10;
+
+    const rectElement = API.createElement({
+      width: 100,
+      height: 100,
+      x: -100,
+      y: -100,
+    });
+
+    h.app.scrollToContent(rectElement, { animate: true });
+
+    expect(window.requestAnimationFrame).toHaveBeenCalled();
+
+    // Since this is an animation, we expect values to change through time.
+    // We'll verify that the scroll values change at 50ms and 100ms
+    expect(h.state.scrollX).toBe(0);
+    expect(h.state.scrollY).toBe(0);
+
+    await waitForNextAnimationFrame();
+
+    const prevScrollX = h.state.scrollX;
+    const prevScrollY = h.state.scrollY;
+
+    expect(h.state.scrollX).not.toBe(0);
+    expect(h.state.scrollY).not.toBe(0);
+
+    await waitForNextAnimationFrame();
+
+    expect(h.state.scrollX).not.toBe(prevScrollX);
+    expect(h.state.scrollY).not.toBe(prevScrollY);
+  });
+
+  it("should animate the scroll but not the zoom", async () => {
+    await render(<ExcalidrawApp />);
+
+    h.state.width = 50;
+    h.state.height = 50;
+
+    const rectElement = API.createElement({
+      width: 100,
+      height: 100,
+      x: 100,
+      y: 100,
+    });
+
+    expect(h.state.scrollX).toBe(0);
+    expect(h.state.scrollY).toBe(0);
+
+    h.app.scrollToContent(rectElement, { animate: true, fitToContent: true });
+
+    expect(window.requestAnimationFrame).toHaveBeenCalled();
+
+    // Since this is an animation, we expect values to change through time.
+    // We'll verify that the zoom/scroll values change in each animation frame
+
+    // zoom is not animated, it should be set to its final value, which in our
+    // case zooms out to 50% so that th element is fully visible (it's 2x large
+    // as the canvas)
+    expect(h.state.zoom.value).toBeLessThanOrEqual(0.5);
+
+    // FIXME I think this should be [-100, -100] so we may have a bug in our zoom
+    // hadnling, alas
+    expect(h.state.scrollX).toBe(25);
+    expect(h.state.scrollY).toBe(25);
+
+    await waitForNextAnimationFrame();
+
+    const prevScrollX = h.state.scrollX;
+    const prevScrollY = h.state.scrollY;
+
+    expect(h.state.scrollX).not.toBe(0);
+    expect(h.state.scrollY).not.toBe(0);
+
+    await waitForNextAnimationFrame();
+
+    expect(h.state.scrollX).not.toBe(prevScrollX);
+    expect(h.state.scrollY).not.toBe(prevScrollY);
+  });
+});

src/utils.ts

@@ -181,6 +181,79 @@ export const throttleRAF = <T extends any[]>(
   return ret;
 };
 
+/**
+ * Exponential ease-out method
+ *
+ * @param {number} k - The value to be tweened.
+ * @returns {number} The tweened value.
+ */
+function easeOut(k: number): number {
+  return 1 - Math.pow(1 - k, 4);
+}
+
+/**
+ * Compute new values based on the same ease function and trigger the
+ * callback through a requestAnimationFrame call
+ *
+ * use `opts` to define a duration and/or an easeFn
+ *
+ * for example:
+ * ```ts
+ * easeToValuesRAF([10, 20, 10], [0, 0, 0], (a, b, c) => setState(a,b, c))
+ * ```
+ *
+ * @param fromValues The initial values, must be numeric
+ * @param toValues The destination values, must also be numeric
+ * @param callback The callback receiving the values
+ * @param opts default to 250ms duration and the easeOut function
+ */
+export const easeToValuesRAF = (
+  fromValues: number[],
+  toValues: number[],
+  callback: (...values: number[]) => void,
+  opts?: { duration?: number; easeFn?: (value: number) => number },
+) => {
+  let canceled = false;
+  let frameId = 0;
+  let startTime: number;
+
+  const duration = opts?.duration || 250; // default animation to 0.25 seconds
+  const easeFn = opts?.easeFn || easeOut; // default the easeFn to easeOut
+
+  function step(timestamp: number) {
+    if (canceled) {
+      return;
+    }
+    if (startTime === undefined) {
+      startTime = timestamp;
+    }
+
+    const elapsed = timestamp - startTime;
+
+    if (elapsed < duration) {
+      // console.log(elapsed, duration, elapsed / duration);
+      const factor = easeFn(elapsed / duration);
+      const newValues = fromValues.map(
+        (fromValue, index) =>
+          (toValues[index] - fromValue) * factor + fromValue,
+      );
+
+      callback(...newValues);
+      frameId = window.requestAnimationFrame(step);
+    } else {
+      // ensure final values are reached at the end of the transition
+      callback(...toValues);
+    }
+  }
+
+  frameId = window.requestAnimationFrame(step);
+
+  return () => {
+    canceled = true;
+    window.cancelAnimationFrame(frameId);
+  };
+};
+
 // https://github.com/lodash/lodash/blob/es/chunk.js
 export const chunk = <T extends any>(
   array: readonly T[],
@@ -616,11 +689,7 @@ export const arrayToMapWithIndex = <T extends { id: string }>(
     return acc;
   }, new Map<string, [element: T, index: number]>());
 
-export const isTestEnv = () =>
-  typeof process !== "undefined" && process.env?.NODE_ENV === "test";
-
-export const isProdEnv = () =>
-  typeof process !== "undefined" && process.env?.NODE_ENV === "production";
+export const isTestEnv = () => process.env.NODE_ENV === "test";
 
 export const wrapEvent = <T extends Event>(name: EVENT, nativeEvent: T) => {
   return new CustomEvent(name, {