vtkRenderWindow renWin
renWin SetSize 300 300
vtkRenderer ren2
ren2 SetViewport 0.0 0.0 1.0 1.0
ren2 SetBackground 0.1 0.2 0.4
renWin AddRenderer ren2
renWin Render

vtkSLCReader negReader
negReader SetFileName "ThisDoesNotExist.slc"
vtkVolumeTextureMapper2D negMapper
negMapper SetInput \
[negReader GetOutput]

vtkPiecewiseFunction negOpacity
negOpacity AddPoint 0 0.0
negOpacity AddPoint 255 0.2
vtkColorTransferFunction negColor
negColor AddRGBPoint 64 1.0 0.0 0.0
negColor AddRGBPoint 128 0.0 0.0 1.0
negColor AddRGBPoint 196 0.0 1.0 0.0

vtkVolumeProperty negProperty
negProperty SetColor negColor
negProperty SetScalarOpacity \
negOpacity
vtkVolume negVolume
negVolume SetMapper negMapper
negVolume SetProperty negProperty
ren2 AddProp negVolume
ren2 ResetCamera
renWin Render