Utkarsh, After reading this question from Olumide, I noticed that ParaView now turns on ZShift for lines and points (vtkProcessModule.cxx, 198-199). I don't know why this is. This effect is turned off when drawing surface+edges (vtkOpenGLCoincidentTopologyResolutionPainter.cxx, 56-58) because it automatically switches to offsetting the polygons the polygons back (vtkOpenGLRepresentationPainter.cxx, 79-85). Should we remove those two lines from vtkProcessModule.cxx?
-Ken On 10/26/09 12:53 AM, "Olumide" <[email protected]> wrote: Hi - I use Paraview not for visualizing datasets, but for inspecting polygonal meshes and the operations I perform on them. My work involves computing various points and line segments on meshes, and I use VTK/Paraview to see if the points and line segments are where they ought to be (if not, I conclude that there's a bug in my code and then proceed to hunt it down). <Digression> Why I use VTK for this task: VTK is the the only publicly available 3d graphics file format I'm aware of that explicitly supports and points, lines, and meshes, and has a viewer for viewing these entities. Most other 3d graphics file formats either support surfaces alone or have no ready-made viewers. </Digression> Lately however, upon closer inspection, I've noticed that many of the points and line segments that I compute appear to hover above the mesh they are computed from and never quite touch it, and points never seem to lie on the line segments they are supposed to. For example, see: http://i17.photobucket.com/albums/b52/videohead/SurfaceError.png (note that the yellow line segment hover above the blue surface in the horizon) After much experimentation, debugging and consultation, I now suspect that this is caused by polygon offset in Paraview, designed to prevent z-fighting. I would therefore like to know: (i.) if my suspicion is correct i.e. Paraview implement polygon offset for preventing z-fighting in this case (ii.) if the above is true, how polygon offset can be disabled without recompiling the source Thanks, - Olumide _______________________________________________ Powered by www.kitware.com Visit other Kitware open-source projects at http://www.kitware.com/opensource/opensource.html Please keep messages on-topic and check the ParaView Wiki at: http://paraview.org/Wiki/ParaView Follow this link to subscribe/unsubscribe: http://www.paraview.org/mailman/listinfo/paraview **** Kenneth Moreland *** Sandia National Laboratories *********** *** *** *** email: [email protected] ** *** ** phone: (505) 844-8919 *** web: http://www.cs.unm.edu/~kmorel
_______________________________________________ Powered by www.kitware.com Visit other Kitware open-source projects at http://www.kitware.com/opensource/opensource.html Please keep messages on-topic and check the ParaView Wiki at: http://paraview.org/Wiki/ParaView Follow this link to subscribe/unsubscribe: http://www.paraview.org/mailman/listinfo/paraview
