Method GetColorsFromPointData

Web/WebGLExporter/vtkWebGLPolyData.cxx:695–783

}

void vtkWebGLPolyData::GetColorsFromPointData(
  unsigned char* color, vtkPointData* pointdata, vtkPolyData* polydata, vtkActor* actor)
{
  vtkDataSetAttributes* attr = (vtkDataSetAttributes*)pointdata;

  int colorSize = attr->GetNormals()->GetDataSize() * 4 / 3;

  vtkDataArray* array;
  if (actor->GetMapper()->GetArrayAccessMode() == VTK_GET_ARRAY_BY_ID)
    array = pointdata->GetArray(actor->GetMapper()->GetArrayId());
  else
    array = pointdata->GetArray(actor->GetMapper()->GetArrayName());

  if (array && actor->GetMapper()->GetScalarVisibility() &&
    actor->GetMapper()->GetArrayName() != nullptr && actor->GetMapper()->GetArrayName()[0] != '\0')
  {
    vtkScalarsToColors* table = actor->GetMapper()->GetLookupTable();
    int colorComponent = table->GetVectorComponent(),
        numberOfComponents = array->GetNumberOfComponents();
    int mode = table->GetVectorMode();
    double mag = 0, rgb[3];
    double alpha = 1.0;

    if (numberOfComponents == 1 && mode == vtkScalarsToColors::MAGNITUDE)
    {
      mode = vtkScalarsToColors::COMPONENT;
      colorComponent = 0;
    }
    for (int i = 0; i < colorSize / 4; i++)
    {
      switch (mode)
      {
        case vtkScalarsToColors::MAGNITUDE:
          mag = 0;
          for (int w = 0; w < numberOfComponents; w++)
            mag += array->GetComponent(i, w) * array->GetComponent(i, w);
          mag = sqrt(mag);
          table->GetColor(mag, &rgb[0]);
          alpha = table->GetOpacity(mag);
          break;
        case vtkScalarsToColors::COMPONENT:
          mag = array->GetComponent(i, colorComponent);
          table->GetColor(mag, &rgb[0]);
          alpha = table->GetOpacity(mag);
          break;
        case vtkScalarsToColors::RGBCOLORS:
          array->GetTuple(i, &rgb[0]);
          alpha = actor->GetProperty()->GetOpacity();
          break;
      }
      color[i * 4 + 0] = (unsigned char)((int)(rgb[0] * 255));
      color[i * 4 + 1] = (unsigned char)((int)(rgb[1] * 255));
      color[i * 4 + 2] = (unsigned char)((int)(rgb[2] * 255));
      color[i * 4 + 3] = (unsigned char)((int)(alpha * 255));
    }
  }
  else
  {