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<DIV><FONT face=Arial size=2><FONT face="Times New Roman" size=3>Hi
everyone<BR><BR>I have a couple of png files (test201.png - test257.png) that
are slices<BR>from a vein system, the veins being white, the surroundings black.
I want to<BR>build a volume from these slices, using the following code (put
together<BR>from various examples):<BR><BR>vtkRenderer ren1 = new
vtkRenderer();<BR>vtkRenderWindow renWin = new
vtkRenderWindow();<BR>renWin.AddRenderer(ren1);<BR>vtkRenderWindowInteractor
iren = new
vtkRenderWindowInteractor();<BR>iren.SetRenderWindow(renWin);<BR><BR>vtkPNGReader
pngreader = new
vtkPNGReader();<BR>pngreader.SetFilePrefix("data/png/test2");<BR>pngreader.SetFilePattern("%s%.2d.png");<BR>pngreader.SetDataExtent(1,256,1,256,0,57);<BR>pngreader.SetFileNameSliceOffset(1);<BR>pngreader.SetDataSpacing(1,1,1);<BR>pngreader.SetDataByteOrderToLittleEndian();<BR>pngreader.UpdateWholeExtent();<BR><BR>vtkPiecewiseFunction
opacityTransferFunction = new
vtkPiecewiseFunction();<BR>opacityTransferFunction.AddPoint(0,
0.0);<BR>opacityTransferFunction.AddPoint(10,
0.259);<BR>opacityTransferFunction.AddPoint(50,
1.0);<BR><BR>vtkColorTransferFunction colorTransferFunction =
new<BR>vtkColorTransferFunction();<BR>colorTransferFunction.AddRGBPoint(0.0,
0.0, 0.0, 0.0);<BR>colorTransferFunction.AddRGBPoint(10.0, 0.259, 0.259,
0.3);<BR>colorTransferFunction.AddRGBPoint(255.0, 1.0, 1.0,
0.3);<BR><BR>vtkVolumeProperty volumeProperty = new
vtkVolumeProperty();<BR>volumeProperty.SetColor(colorTransferFunction);<BR>volumeProperty.SetScalarOpacity(opacityTransferFunction);<BR>volumeProperty.SetInterpolationTypeToLinear();<BR>volumeProperty.ShadeOff();<BR><BR>vtkVolumeRayCastCompositeFunction
compositeFunction =
new<BR>vtkVolumeRayCastCompositeFunction();<BR>vtkVolumeRayCastMapper
volumeMapper = new
vtkVolumeRayCastMapper();<BR>volumeMapper.SetVolumeRayCastFunction(compositeFunction);<BR>volumeMapper.SetInput(pngreader.GetOutput());<BR><BR>vtkVolume
volume = new
vtkVolume();<BR>volume.SetMapper(volumeMapper);<BR>volume.SetProperty(volumeProperty);<BR>ren1.AddVolume(volume);<BR>ren1.SetBackground(0.1,
0.2, 0.4);<BR>renWin.Render();<BR>iren.Initialize();<BR><BR>All I get from this
is a blue window with a few yellow dots. The window<BR>immediately vanishes
after half a second.<BR>What am I doing wrong?<BR><BR>Thanks in
advance</FONT><BR></FONT></DIV></BODY></HTML>