Backface culling wireframe and point representations
This issue was created automatically from an original Mantis Issue. Further discussion may take place here.
I've had some code for backface culling triangles/triangle strips in wireframe and points representations that I've just updated for the recent changes to vtkOpenGLPolyDataMapper for doubles. It usefull for exporting vector graphics with vtkGL2PSExporter of a model with edge visibility. Its passed through the regression testing without a hitch (Common/PrintSelfCheck failed though).
Presently, VTK draws lines in wireframe mode. This code works by drawing triangles in wireframe mode and using glPolygonMode(GL_FRONT, GL_LINE) to switch the representation. The drawback is that its slower to render triangles than lines, so it may be quicker to render a model in wireframe with BackfaceCullingOff than with BackfaceCullingOn (it depends a lot on your graphics card)... It doesn't effect the performance of any surface representation or wireframe representation with BackfaceCullingOff.
The diffs for vtkOpenGLPolyDataMapper.cxx and and vtkOpenGLProperty.cxx are below. You can get the modified files here: http://www.bioengineering-research.com/vtk/vtkOpenGLProperty.cxx http://www.bioengineering-research.com/vtk/vtkOpenGLPolyDataMapper.cxx