Method SetRGBAPixelData

Rendering/WebGPU/vtkWebGPURenderWindow.cxx:1524–1612

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int vtkWebGPURenderWindow::SetRGBAPixelData(
  int x, int y, int x2, int y2, float* data, int front, int blend /*=0*/, int right /*=0*/)
{
  vtkWebGPUCheckUnconfiguredWithReturn(this, 0);
  auto device = this->WGPUConfiguration->GetDevice();
  if (device == nullptr)
  {
    vtkErrorMacro(<< "Cannot set RGBA pixel data because WebGPU device is not ready!");
    return 0;
  }
  (void)front;
  (void)blend;
  (void)right;
  const int nComp = 4;
  int width = (x2 - x) + 1;
  int height = (y2 - y) + 1;
  int bytesPerRow = vtkWebGPUConfiguration::Align(width * nComp, 256);
  int size = bytesPerRow * height;

  const std::string label = "StagingRGBAPixelData-" + this->GetObjectDescription();
  wgpu::BufferDescriptor desc;
  desc.mappedAtCreation = true;
  desc.label = label.c_str();
  desc.size = size;
  desc.usage = wgpu::BufferUsage::CopySrc;

  this->StagingPixelData.Buffer = this->WGPUConfiguration->CreateBuffer(desc);
  if (this->StagingPixelData.Buffer == nullptr)
  {
    vtkErrorMacro(<< "Failed to create buffer for staging pixel data using device "
                  << device.Get());
    return 0;
  }
  auto mapped =
    reinterpret_cast<unsigned char*>(this->StagingPixelData.Buffer.GetMappedRange(0, size));
  if (mapped == nullptr)
  {
    vtkErrorMacro(<< "Failed to map staging pixel data!");
    return 0;
  }
  unsigned long dstIdx = 0;
  unsigned long srcIdx = 0;
  const unsigned long nPad = bytesPerRow - width * nComp;
  int componentMap[4] = {};
  if (this->ColorAttachment.Format == wgpu::TextureFormat::BGRA8Unorm)
  {
    componentMap[0] = 2;
    componentMap[1] = 1;
    componentMap[2] = 0;
    componentMap[3] = 3;
  }
  else if (this->ColorAttachment.Format == wgpu::TextureFormat::RGBA8Unorm)
  {
    componentMap[0] = 0;
    componentMap[1] = 1;
    componentMap[2] = 2;
    componentMap[3] = 3;
  }