HarmonyOS 鸿蒙Next 离屏渲染中canvas能嵌套canvas吗

可以使用：OffscreenCanvas
参考链接：https://developer.huawei.com/consumer/cn/doc/harmonyos-references-V5/ts-components-offscreencanvas-V5#offscreencanvas%E6%94%AF%E6%8C%81%E5%B9%B6%E5%8F%91%E7%BA%BF%E7%A8%8B%E7%BB%98%E5%88%B6

参考demo

import { MessageEvents, ThreadWorkerGlobalScope, worker } from '@kit.ArkTS'

const workerPort: ThreadWorkerGlobalScope = worker.workerPort;

workerPort.onmessage = (e: MessageEvents) => {
  if (e.data.myOffCanvas) {
    let offCanvas: OffscreenCanvas = e.data.myOffCanvas
    let offContext = offCanvas.getContext("2d")
    offContext.fillStyle = '#ffe91616'
    offContext.fillRect(0, 0, 100,50)
    let image = offCanvas.transferToImageBitmap()
    workerPort.postMessage({ myImage: image });
  }
}

import { MessageEvents, ThreadWorkerGlobalScope, worker } from '@kit.ArkTS';

@Entry
@Component
struct CanvasPage {
  private settings: RenderingContextSettings = new RenderingContextSettings(true);
  private context: CanvasRenderingContext2D = new CanvasRenderingContext2D(this.settings);
  private offCanvas: OffscreenCanvas = new OffscreenCanvas(200, 300)
  private myWorker = new worker.ThreadWorker('entry/ets/pages/work.ts');
  build() {
    Flex({ direction: FlexDirection.Row, alignItems: ItemAlign.Start, justifyContent: FlexAlign.Start }) {
      Stack() {
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .borderWidth(5)
          .borderColor('#057D02')
          .backgroundColor('#FFFFFF')
          .onReady(() => {
            let offContext = this.offCanvas.getContext("2d", this.settings)
            offContext.fillStyle = '#CDCDCD'
            offContext.fillRect(0, 0, this.offCanvas.width, 150)
            let image = this.offCanvas.transferToImageBitmap()
            this.context.setTransform(1, 0, 0, 1, 50, 200)
            this.context.transferFromImageBitmap(image)
          })
        Canvas(this.context)
          .width('100%')
          .height('100%')
          .borderWidth(5)
          .borderColor('#057D02')
          .backgroundColor('#FFFFFF')
          .onReady(() => {
            let offCanvas = new OffscreenCanvas(600, 800)
            this.myWorker.postMessage({ myOffCanvas: offCanvas });
            this.myWorker.onmessage = (e): void => {
              if (e.data.myImage) {
                let image: ImageBitmap = e.data.myImage
                this.context.transferFromImageBitmap(image)
              }
            }
          })

      }
    }.width('100%').height('100%')
  }
}

注意在entry下的build-json5 配置

"sourceOption": {
      "workers": [
        "./src/main/ets/pages/work.ets"
      ],
    }