Method doRasterize

apps/managed_context_example/ManagedContextExample.tsx:141–180

()

  }

  private async doRasterize(): Promise<Asset> {
    const [componentWidth, componentHeight] = this.getComponentSize();
    const context = createManagedContext({
      embeddedPlatformViewRasterMethod: this.state.rasterMethod,
      deltaRasterization: true,
    });
    context.render(() => {
      <InnerComponent />;
    });

    await context.onAllAssetsLoaded();

    await context.layout(componentWidth, componentHeight, false);

    const { frame } = await context.draw();

    const scale = Device.getDisplayScale() / DOWNSCALE_RATIO[this.state.downscaleRatioIndex];
    const rasterWidth = Math.floor(scale * componentWidth);
    const rasterHeight = Math.floor(scale * componentHeight);

    const bytesPerPixel = 4;

    const bitmap = createBitmap({
      width: rasterWidth,
      height: rasterHeight,
      colorType: BitmapColorType.RGBA8888,
      alphaType: BitmapAlphaType.OPAQUE,
      rowBytes: rasterWidth * bytesPerPixel,
    });

    frame.rasterInto(bitmap, true);

    const buffer = bitmap.encode(ImageEncoding.PNG, 1.0);

    frame.dispose();
    bitmap.dispose();
    context.dispose();

    return makeAssetFromBytes(buffer);
  }
}

const styles = {};