[vtkusers] Colorscale Problem

[WolfgangZillig]

Hello,

I want to generate some grapfics from results from a finite element 
calculation. It works quite well but when I tried to generate a scalebar 
(out of a manually entered grid) I got some strange results. I want to 
have the color rangeing from red over yellow to blue. I've defined this 
range by:

	min=0.50
	max=0.80
	avg=(min+max)/2.0

	aTriangleMapper.SetInput(aTriangleGrid)
	colorTransferFunction = vtk.vtkColorTransferFunction()
	colorTransferFunction.AddRGBPoint(min, 0.0, 0.0, 1.0)
	colorTransferFunction.AddRGBPoint(avg, 1.0, 1.0, 0.0)
	colorTransferFunction.AddRGBPoint(max, 1.0, 0.0, 0.0)
	aTriangleMapper.SetLookupTable(colorTransferFunction)


It looks for me that this range can not be drawn in one element of my 
grid. In the output from my calculations this is not a problem as there 
is not a that huge difference over one single element but in the mesh of 
my scalbar I got strange results. See included pictures.

So my question is: is this a limitation of vtk or do I do something wrong?

Kind regards
Wolfgang Zillig


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