Method EvaluateGradient

Common/DataModel/vtkPlanes.cxx:108–140

------------------------------------------------------------------------------ Evaluate planes gradient.

//------------------------------------------------------------------------------
// Evaluate planes gradient.
void vtkPlanes::EvaluateGradient(double x[3], double n[3])
{
  int numPlanes, i;
  double val, maxVal;
  double nTemp[3];
  double pTemp[3];

  if (!this->Points || !this->Normals)
  {
    vtkErrorMacro(<< "Please define points and/or normals!");
    return;
  }

  if ((numPlanes = this->Points->GetNumberOfPoints()) != this->Normals->GetNumberOfTuples())
  {
    vtkErrorMacro(<< "Number of normals/points inconsistent!");
    return;
  }

  for (maxVal = -VTK_DOUBLE_MAX, i = 0; i < numPlanes; i++)
  {
    this->Normals->GetTuple(i, nTemp);
    this->Points->GetPoint(i, pTemp);
    val = this->Plane->Evaluate(nTemp, pTemp, x);
    if (val > maxVal)
    {
      maxVal = val;
      n[0] = nTemp[0];
      n[1] = nTemp[1];
      n[2] = nTemp[2];
    }
  }
}

//------------------------------------------------------------------------------
void vtkPlanes::SetFrustumPlanes(double planes[24])