Oluminde, It makes sense to provide an option in the "Settings" dialog to tweak/disable offsetting for resolving z-fighting. I've added a feature request to the bug tracker: http://paraview.org/Bug/view.php?id=9801
To fix this without recompiling, here's a crazy hack to overcome this issue in builtin mode (i.e. when not connected to server): Before loading any datasets * open python shell * Run the following commands: > import os > if os.name == "posix": > from libvtkRendering.so import vtkMapper > else: > from vtkRenderingPython import vtkMapper > vtkMapper.SetResolveCoincidentTopologyToOff() If connected to a server, you can run the same python commands as part of the python script for a programmable source or filter. Utkarsh On Fri, Oct 30, 2009 at 6:48 AM, Utkarsh Ayachit <[email protected]> wrote: > Ken, > > Offsetting the points/lines handles the cases when people try to > render two overlapping datasets: one as surface and other as > wireframe, and they don't necessarily want to show surface with edges > (say they want scalar coloring for both surface and the wireframe). I > believe Jean Favre has several such use cases. > > Utkarsh > > On Mon, Oct 26, 2009 at 1:18 PM, Moreland, Kenneth <[email protected]> wrote: >> 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
