[vtkusers] VTK7 and PolygonOffset

[marcin.krotkiewski]

Hello,

I am wondering if there were any major changes between VTK6.3 and VTK7 
in how SetResolveCoincidentTopologyPolygonOffsetParameters in the 
OpenGL2 backend works.

I have been using OpenGL2 and polygon offset to display contour lines on 
3D surface meshes (digital elevation models). The parameters I use are 
(1, mesh_size), where mesh_size is some value related to the 'physical' 
distance between nodes in my surface meshes. In VTK7 that gives very 
wrong results. To get similar behavior I seem to have to use (2, 1), 
regardless of 'physical' distances between the mesh nodes.

Could anyone shed some light on that?

Thanks!

Marcin