<P>
>>I have a more or less sphere-like surface and want to have a direct >>link on this surface from a given start- and endpoint on this surface.<BR>
<BR>
If your surface is generated from vtkSphereSource, you can find the points of sphere using:<BR>
<BR>
cs = vtk.vtkSphereSource()<BR>
cs.Update()<BR>
ps = cs.GetOutput()<BR>
points = ps.GetPoints()<BR>
<BR>
Then you can write a simple function which will calculate the distance between your point and points on the sphere. You can now identify the point nearest to your given point. Once you have the 2 points you can draw a line between them. <BR>
<BR>
If you yourself have created the surface you can always do the same logic easily.<BR>
<BR>
>>I hope you understand the problem and may give me some ideas how to >>show the shortest link on the surface between the to points.<BR>
</P>
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