feat: Animation and interactive scene support added

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

packages/excalidraw/components/App.tsx

@@ -1805,6 +1805,7 @@ class App extends React.Component<AppProps, AppState> {
                           />
                         )}
                         <InteractiveCanvas
+                          app={this}
                           containerRef={this.excalidrawContainerRef}
                           canvas={this.interactiveCanvas}
                           elementsMap={elementsMap}

packages/excalidraw/components/canvases/InteractiveCanvas.tsx

@@ -5,6 +5,15 @@ import {
   isShallowEqual,
   sceneCoordsToViewportCoords,
 } from "@excalidraw/common";
+import { AnimationController } from "@excalidraw/excalidraw/renderer/animation";
+
+import type {
+  InteractiveCanvasRenderConfig,
+  InteractiveSceneRenderAnimationState,
+  InteractiveSceneRenderConfig,
+  RenderableElementsMap,
+  RenderInteractiveSceneCallback,
+} from "@excalidraw/excalidraw/scene/types";
 
 import type {
   NonDeletedExcalidrawElement,
@@ -12,15 +21,14 @@ import type {
 } from "@excalidraw/element/types";
 
 import { t } from "../../i18n";
-import { isRenderThrottlingEnabled } from "../../reactUtils";
 import { renderInteractiveScene } from "../../renderer/interactiveScene";
 
 import type {
-  InteractiveCanvasRenderConfig,
-  RenderableElementsMap,
-  RenderInteractiveSceneCallback,
-} from "../../scene/types";
-import type { AppState, Device, InteractiveCanvasAppState } from "../../types";
+  AppClassProperties,
+  AppState,
+  Device,
+  InteractiveCanvasAppState,
+} from "../../types";
 import type { DOMAttributes } from "react";
 
 type InteractiveCanvasProps = {
@@ -36,6 +44,7 @@ type InteractiveCanvasProps = {
   appState: InteractiveCanvasAppState;
   renderScrollbars: boolean;
   device: Device;
+  app: AppClassProperties;
   renderInteractiveSceneCallback: (
     data: RenderInteractiveSceneCallback,
   ) => void;
@@ -70,8 +79,11 @@ type InteractiveCanvasProps = {
   >;
 };
 
+export const INTERACTIVE_SCENE_ANIMATION_KEY = "animateInteractiveScene";
+
 const InteractiveCanvas = (props: InteractiveCanvasProps) => {
   const isComponentMounted = useRef(false);
+  const rendererParams = useRef(null as InteractiveSceneRenderConfig | null);
 
   useEffect(() => {
     if (!isComponentMounted.current) {
@@ -128,29 +140,61 @@ const InteractiveCanvas = (props: InteractiveCanvasProps) => {
         )) ||
       "#6965db";
 
-    renderInteractiveScene(
-      {
-        canvas: props.canvas,
-        elementsMap: props.elementsMap,
-        visibleElements: props.visibleElements,
-        selectedElements: props.selectedElements,
-        allElementsMap: props.allElementsMap,
-        scale: window.devicePixelRatio,
-        appState: props.appState,
-        renderConfig: {
-          remotePointerViewportCoords,
-          remotePointerButton,
-          remoteSelectedElementIds,
-          remotePointerUsernames,
-          remotePointerUserStates,
-          selectionColor,
-          renderScrollbars: props.renderScrollbars,
-        },
-        device: props.device,
-        callback: props.renderInteractiveSceneCallback,
+    rendererParams.current = {
+      app: props.app,
+      canvas: props.canvas,
+      elementsMap: props.elementsMap,
+      visibleElements: props.visibleElements,
+      selectedElements: props.selectedElements,
+      allElementsMap: props.allElementsMap,
+      scale: window.devicePixelRatio,
+      appState: props.appState,
+      renderConfig: {
+        remotePointerViewportCoords,
+        remotePointerButton,
+        remoteSelectedElementIds,
+        remotePointerUsernames,
+        remotePointerUserStates,
+        selectionColor,
+        renderScrollbars: props.renderScrollbars,
       },
-      isRenderThrottlingEnabled(),
-    );
+      device: props.device,
+      callback: props.renderInteractiveSceneCallback,
+      animationState: {
+        bindingHighlight: undefined,
+      },
+      deltaTime: 0,
+    };
+
+    if (!AnimationController.running(INTERACTIVE_SCENE_ANIMATION_KEY)) {
+      AnimationController.start<InteractiveSceneRenderAnimationState>(
+        INTERACTIVE_SCENE_ANIMATION_KEY,
+        ({ deltaTime, state }) => {
+          const nextAnimationState = renderInteractiveScene(
+            {
+              ...rendererParams.current!,
+              deltaTime,
+              animationState: state,
+            },
+            false,
+          ).animationState;
+
+          if (nextAnimationState) {
+            for (const key in nextAnimationState) {
+              if (
+                nextAnimationState[
+                  key as keyof InteractiveSceneRenderAnimationState
+                ] !== undefined
+              ) {
+                return nextAnimationState;
+              }
+            }
+          }
+
+          return undefined;
+        },
+      );
+    }
   });
 
   return (

packages/excalidraw/renderer/animation.ts

@@ -0,0 +1,84 @@
+import { isRenderThrottlingEnabled } from "../reactUtils";
+
+export type Animation<R extends object> = (params: {
+  deltaTime: number;
+  state?: R;
+}) => R | null | undefined;
+
+export class AnimationController {
+  private static isRunning = false;
+  private static animations = new Map<
+    string,
+    {
+      animation: Animation<any>;
+      lastTime: number;
+      state: any;
+    }
+  >();
+
+  static start<R extends object>(key: string, animation: Animation<R>) {
+    const initialState = animation({
+      deltaTime: 0,
+      state: undefined,
+    });
+
+    if (initialState) {
+      AnimationController.animations.set(key, {
+        animation,
+        lastTime: 0,
+        state: initialState,
+      });
+
+      if (!AnimationController.isRunning) {
+        AnimationController.isRunning = true;
+
+        if (isRenderThrottlingEnabled()) {
+          requestAnimationFrame(AnimationController.tick);
+        } else {
+          setTimeout(AnimationController.tick, 0);
+        }
+      }
+    }
+  }
+
+  private static tick() {
+    if (AnimationController.animations.size > 0) {
+      for (const [key, animation] of AnimationController.animations) {
+        const now = performance.now();
+        const deltaTime =
+          animation.lastTime === 0 ? 0 : now - animation.lastTime;
+
+        const state = animation.animation({
+          deltaTime,
+          state: animation.state,
+        });
+
+        if (!state) {
+          AnimationController.animations.delete(key);
+
+          if (AnimationController.animations.size === 0) {
+            AnimationController.isRunning = false;
+            return;
+          }
+        } else {
+          animation.lastTime = now;
+          animation.state = state;
+        }
+      }
+
+      if (isRenderThrottlingEnabled()) {
+        requestAnimationFrame(AnimationController.tick);
+      } else {
+        setTimeout(AnimationController.tick, 0);
+      }
+    }
+  }
+
+  static running(key: string) {
+    return AnimationController.animations.has(key);
+  }
+
+  static cancel(key: string) {
+    AnimationController.animations.delete(key);
+  }
+}

packages/excalidraw/renderer/interactiveScene.ts

@@ -735,7 +735,14 @@ const _renderInteractiveScene = ({
   appState,
   renderConfig,
   device,
-}: InteractiveSceneRenderConfig) => {
+  animationState,
+  deltaTime,
+}: InteractiveSceneRenderConfig): {
+  scrollBars?: ReturnType<typeof getScrollBars>;
+  atLeastOneVisibleElement: boolean;
+  elementsMap: RenderableElementsMap;
+  animationState?: typeof animationState;
+} => {
   if (canvas === null) {
     return { atLeastOneVisibleElement: false, elementsMap };
   }
@@ -745,6 +752,8 @@ const _renderInteractiveScene = ({
     scale,
   );
 
+  const nextAnimationState = animationState;
+
   const context = bootstrapCanvas({
     canvas,
     scale,
@@ -1191,6 +1200,7 @@ const _renderInteractiveScene = ({
     scrollBars,
     atLeastOneVisibleElement: visibleElements.length > 0,
     elementsMap,
+    animationState: nextAnimationState,
   };
 };
 

packages/excalidraw/scene/types.ts

@@ -88,7 +88,12 @@ export type StaticSceneRenderConfig = {
   renderConfig: StaticCanvasRenderConfig;
 };
 
+export type InteractiveSceneRenderAnimationState = {
+  bindingHighlight: { runtime: number } | undefined;
+};
+
 export type InteractiveSceneRenderConfig = {
+  app: AppClassProperties;
   canvas: HTMLCanvasElement | null;
   elementsMap: RenderableElementsMap;
   visibleElements: readonly NonDeletedExcalidrawElement[];
@@ -99,6 +104,8 @@ export type InteractiveSceneRenderConfig = {
   renderConfig: InteractiveCanvasRenderConfig;
   device: Device;
   callback: (data: RenderInteractiveSceneCallback) => void;
+  animationState?: InteractiveSceneRenderAnimationState;
+  deltaTime: number;
 };
 
 export type NewElementSceneRenderConfig = {