Method SetupDepthPass

Rendering/VolumeOpenGL2/vtkOpenGLGPUVolumeRayCastMapper.cxx:1995–2060

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//------------------------------------------------------------------------------
void vtkOpenGLGPUVolumeRayCastMapper::vtkInternal::SetupDepthPass(vtkRenderer* ren)
{
  if (this->Parent->ImageSampleDistance != 1.f)
  {
    this->WindowSize[0] /= this->Parent->ImageSampleDistance;
    this->WindowSize[1] /= this->Parent->ImageSampleDistance;
  }

  if ((this->LastDepthPassWindowSize[0] != this->WindowSize[0]) ||
    (this->LastDepthPassWindowSize[1] != this->WindowSize[1]))
  {
    this->LastDepthPassWindowSize[0] = this->WindowSize[0];
    this->LastDepthPassWindowSize[1] = this->WindowSize[1];
    this->ReleaseDepthPassGraphicsResources(ren->GetRenderWindow());
  }

  if (!this->DPFBO)
  {
    this->DPFBO = vtkOpenGLFramebufferObject::New();
  }

  vtkOpenGLRenderWindow* renWin = vtkOpenGLRenderWindow::SafeDownCast(ren->GetRenderWindow());
  this->DPFBO->SetContext(renWin);

  renWin->GetState()->PushFramebufferBindings();
  this->DPFBO->Bind();
  this->DPFBO->InitializeViewport(this->WindowSize[0], this->WindowSize[1]);

  if (!this->DPDepthBufferTextureObject || !this->DPColorTextureObject)
  {
    this->DPDepthBufferTextureObject = vtkTextureObject::New();
    this->DPDepthBufferTextureObject->SetContext(renWin);
    this->DPDepthBufferTextureObject->AllocateDepth(
      this->WindowSize[0], this->WindowSize[1], vtkTextureObject::Native);
    this->DPDepthBufferTextureObject->Activate();
    this->DPDepthBufferTextureObject->SetMinificationFilter(vtkTextureObject::Nearest);
    this->DPDepthBufferTextureObject->SetMagnificationFilter(vtkTextureObject::Nearest);
    this->DPDepthBufferTextureObject->SetAutoParameters(0);
    this->DPDepthBufferTextureObject->Bind();

    this->DPColorTextureObject = vtkTextureObject::New();

    this->DPColorTextureObject->SetContext(renWin);
    this->DPColorTextureObject->Create2D(
      this->WindowSize[0], this->WindowSize[1], 4, VTK_UNSIGNED_CHAR, false);
    this->DPColorTextureObject->Activate();
    this->DPColorTextureObject->SetMinificationFilter(vtkTextureObject::Nearest);
    this->DPColorTextureObject->SetMagnificationFilter(vtkTextureObject::Nearest);
    this->DPColorTextureObject->SetAutoParameters(0);

    this->DPFBO->AddDepthAttachment(this->DPDepthBufferTextureObject);

    this->DPFBO->AddColorAttachment(0U, this->DPColorTextureObject);
  }

  this->DPFBO->ActivateDrawBuffers(1);
  this->DPFBO->CheckFrameBufferStatus(GL_FRAMEBUFFER);