Here I am again…
It’s been a long time since I posted one of my problems… Well,let’s go…
I am working on a Computational Fluids Dynamics post-processor.
I am trying to visualize data on the grid by assigning one color per vertex and then render the quads. Of course I set the ShadeModel to GL_SMOOTH.
Everything works perfectly except for one thing that is totally OpenGL-Related.
When you draw a quad (or the two triangles that constitute this quad) with a different color for each vertex, you always have a problem on one of the diagonals (the one that joins the two triangles). What I mean is that you can actually SEE the diagonal !
It is not difficult to guess that this happens because of OpenGL interpolation method and I won’t blame it. The thing is, I would like to know if anyone has got an idea to prevent things like that from happening.
Well, the obvious idea is to tesselate so that the colors for each triangle are so close that you can not notice the artefact but when you already have 1/2million cells or more, you really want to avoid adding more things to display !
Hope someone has got an idea !