Method deviceCopyFromGPU

web/src/webgpu.ts:1002–1032

(
    from: GPUPointer,
    fromOffset: number,
    to: Pointer,
    nbytes: number
  )

  }

  private deviceCopyFromGPU(
    from: GPUPointer,
    fromOffset: number,
    to: Pointer,
    nbytes: number
  ): void {
    // Flush batched compute passes before the readback copy.
    this.flushCommands();
    const gpuTemp = this.getOrCreateReadStagingBuffer(nbytes);

    const copyEncoder = this.device.createCommandEncoder();
    copyEncoder.copyBufferToBuffer(
      this.gpuBufferFromPtr(from),
      fromOffset,
      gpuTemp,
      0,
      nbytes
    );
    const copyCommands = copyEncoder.finish();
    this.device.queue.submit([copyCommands]);

    const readPromise = gpuTemp.mapAsync(GPUMapMode.READ).then(() => {
      const data = gpuTemp.getMappedRange(0, nbytes);
      this.memory.storeRawBytes(to, new Uint8Array(data));
      this.recycleReadStagingBuffer(gpuTemp);
    });
    // Chain with any existing pending read so sync() awaits all of them.
    this.pendingGPUToCPUCopy = this.pendingGPUToCPUCopy
      ? this.pendingGPUToCPUCopy.then(() => readPromise)
      : readPromise;
  }

  private deviceCopyWithinGPU(
    from: GPUPointer,