If your data are triangles in a .stl file or .vtk file you can load it and measure distances by use of a tool found here: http://www.lab3d.odont.ku.dk/landmarker/ Tron -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://www.vtk.org/pipermail/vtkusers/attachments/20080310/75db35b8/attachment.htm>