Method AdjustZBuffer

Common/Transforms/vtkPerspectiveTransform.cxx:234–244

------------------------------------------------------------------------------ Utility for adjusting the min/max range of the Z buffer. Usually the oldZMin, oldZMax are [-1,+1] as per Ortho and Frustum, and you are mapping the Z buffer to a new range.

// the oldZMin, oldZMax are [-1,+1] as per Ortho and Frustum, and
// you are mapping the Z buffer to a new range.
void vtkPerspectiveTransform::AdjustZBuffer(
  double oldZMin, double oldZMax, double newZMin, double newZMax)
{
  double matrix[4][4];
  vtkMatrix4x4::Identity(*matrix);

  matrix[2][2] = (newZMax - newZMin) / (oldZMax - oldZMin);
  matrix[2][3] = (newZMin * oldZMax - newZMax * oldZMin) / (oldZMax - oldZMin);

  this->Concatenate(*matrix);
}

//------------------------------------------------------------------------------
// The orthographic perspective maps [xmin,xmax], [ymin,ymax], [-znear,-zfar]