[Perf] RLottie: Add GPU-acceleration with ImageBitmap

src/lib/rlottie/RLottie.ts

@@ -16,8 +16,8 @@ interface Params {
   coords?: { x: number; y: number };
 }
 
-type Frames = ArrayBuffer[];
-type Chunks = (Frames | undefined)[];
+type Frame = ImageBitmap;
+type Chunks = (Frame[] | undefined)[];
 
 // TODO Consider removing chunks
 const CHUNK_SIZE = 1;
@@ -49,6 +49,8 @@ class RLottie {
 
   private imgSize!: number;
 
+  private imageData!: ImageData;
+
   private msPerFrame = 1000 / 60;
 
   private reduceFactor = 1;
@@ -263,6 +265,7 @@ class RLottie {
 
     if (!this.imgSize) {
       this.imgSize = imgSize;
+      this.imageData = new ImageData(imgSize, imgSize);
     }
 
     if (this.isRendererInited) {
@@ -299,6 +302,7 @@ class RLottie {
         this.tgsUrl,
         this.imgSize,
         this.params.isLowPriority,
+        this.customColor,
         this.onRendererInit.bind(this),
       ],
     });
@@ -407,26 +411,14 @@ class RLottie {
           return false;
         }
 
-        const arr = new Uint8ClampedArray(frame);
-        if (this.customColor) {
-          for (let i = 0; i < arr.length; i += 4) {
-            /* eslint-disable prefer-destructuring */
-            arr[i] = this.customColor[0];
-            arr[i + 1] = this.customColor[1];
-            arr[i + 2] = this.customColor[2];
-            /* eslint-enable prefer-destructuring */
-          }
-        }
-
-        const imageData = new ImageData(arr, this.imgSize, this.imgSize);
-
         this.containers.forEach((containerData) => {
           const {
             ctx, isLoaded, isPaused, coords: { x, y } = {}, onLoad,
           } = containerData;
 
           if (!isLoaded || !isPaused) {
-            ctx.putImageData(imageData, x || 0, y || 0);
+            ctx.clearRect(x || 0, y || 0, this.imgSize, this.imgSize);
+            ctx.drawImage(frame, x || 0, y || 0);
           }
 
           if (!isLoaded) {
@@ -511,6 +503,17 @@ class RLottie {
     return chunk[indexInChunk];
   }
 
+  private setFrame(frameIndex: number, frame: Frame) {
+    const chunkIndex = this.getChunkIndex(frameIndex);
+    const indexInChunk = this.getFrameIndexInChunk(frameIndex);
+    const chunk = this.chunks[chunkIndex];
+    if (!chunk) {
+      return;
+    }
+
+    chunk[indexInChunk] = frame;
+  }
+
   private getFrameIndexInChunk(frameIndex: number) {
     const chunkIndex = this.getChunkIndex(frameIndex);
     return frameIndex - chunkIndex * this.chunkSize;
@@ -557,7 +560,7 @@ class RLottie {
     }
   }
 
-  private onFrameLoad(frameIndex: number, arrayBuffer: ArrayBuffer) {
+  private onFrameLoad(frameIndex: number, imageBitmap: ImageBitmap) {
     const chunkIndex = this.getChunkIndex(frameIndex);
     const chunk = this.chunks[chunkIndex];
     // Frame can be skipped and chunk can be already cleaned up
@@ -565,7 +568,7 @@ class RLottie {
       return;
     }
 
-    chunk[this.getFrameIndexInChunk(frameIndex)] = arrayBuffer;
+    chunk[this.getFrameIndexInChunk(frameIndex)] = imageBitmap;
 
     if (this.isWaiting) {
       this.doPlay();

src/lib/rlottie/rlottie.worker.ts

@@ -33,6 +33,8 @@ const renderers = new Map<string, {
   imgSize: number;
   reduceFactor: number;
   handle: any;
+  imageData: ImageData;
+  customColor?: [number, number, number];
 }>();
 
 async function init(
@@ -40,6 +42,7 @@ async function init(
   tgsUrl: string,
   imgSize: number,
   isLowPriority: boolean,
+  customColor: [number, number, number] | undefined,
   onInit: CancellableCallback,
 ) {
   if (!rLottieApi) {
@@ -52,9 +55,14 @@ async function init(
   const framesCount = rLottieApi.loadFromData(handle, stringOnWasmHeap);
   rLottieApi.resize(handle, imgSize, imgSize);
 
+  const imageData = new ImageData(imgSize, imgSize);
+
   const { reduceFactor, msPerFrame, reducedFramesCount } = calcParams(json, isLowPriority, framesCount);
 
-  renderers.set(key, { imgSize, reduceFactor, handle });
+  renderers.set(key, {
+    imgSize, reduceFactor, handle, imageData, customColor,
+  });
+
   onInit(reduceFactor, msPerFrame, reducedFramesCount);
 }
 
@@ -74,6 +82,7 @@ async function changeData(
   const framesCount = rLottieApi.loadFromData(handle, stringOnWasmHeap);
 
   const { reduceFactor, msPerFrame, reducedFramesCount } = calcParams(json, isLowPriority, framesCount);
+
   onInit(reduceFactor, msPerFrame, reducedFramesCount);
 }
 
@@ -110,7 +119,9 @@ async function renderFrames(
     await rLottieApiPromise;
   }
 
-  const { imgSize, reduceFactor, handle } = renderers.get(key)!;
+  const {
+    imgSize, reduceFactor, handle, imageData, customColor,
+  } = renderers.get(key)!;
 
   for (let i = fromIndex; i <= toIndex; i++) {
     const realIndex = i * reduceFactor;
@@ -118,8 +129,26 @@ async function renderFrames(
     rLottieApi.render(handle, realIndex);
     const bufferPointer = rLottieApi.buffer(handle);
     const data = Module.HEAPU8.subarray(bufferPointer, bufferPointer + (imgSize * imgSize * 4));
-    const arrayBuffer = new Uint8ClampedArray(data).buffer;
-    onProgress(i, arrayBuffer);
+
+    if (customColor) {
+      const arr = new Uint8ClampedArray(data);
+      applyColor(arr, customColor);
+      imageData.data.set(arr);
+    } else {
+      imageData.data.set(data);
+    }
+
+    const imageBitmap = await createImageBitmap(imageData);
+
+    onProgress(i, imageBitmap);
+  }
+}
+
+function applyColor(arr: Uint8ClampedArray, color: [number, number, number]) {
+  for (let i = 0; i < arr.length; i += 4) {
+    arr[i] = color[0];
+    arr[i + 1] = color[1];
+    arr[i + 2] = color[2];
   }
 }
 

src/util/createWorkerInterface.ts

@@ -25,7 +25,7 @@ export default function createInterface(api: Record<string, Function>) {
                 type: 'methodCallback',
                 messageId,
                 callbackArgs,
-              }, lastArg instanceof ArrayBuffer ? [lastArg] : undefined);
+              }, isTransferable(lastArg) ? [lastArg] : undefined);
             };
 
             callbackState.set(messageId, callback);
@@ -78,6 +78,10 @@ export default function createInterface(api: Record<string, Function>) {
   };
 }
 
+function isTransferable(obj: any) {
+  return obj instanceof ArrayBuffer || obj instanceof ImageBitmap;
+}
+
 function handleErrors() {
   self.onerror = (e) => {
     // eslint-disable-next-line no-console
@@ -92,9 +96,9 @@ function handleErrors() {
   });
 }
 
-function sendToOrigin(data: WorkerMessageData, arrayBuffers?: ArrayBuffer[]) {
-  if (arrayBuffers) {
-    postMessage(data, arrayBuffers);
+function sendToOrigin(data: WorkerMessageData, transferables?: Transferable[]) {
+  if (transferables) {
+    postMessage(data, transferables);
   } else {
     postMessage(data);
   }