Application crash with Intel video cards

In the OpenCascade version 5.2 our application works well and no crashes are happen.
In the OpenCascade version 6.3 our application crashes only when working with Intel video cards (NVIDEA works well).
It is happen when TopAbs_FACE is selected by:
The crash is happen on the OpenGL level in draw_array function of OpenGl_PrimitiveArray.c file of TKOpenGL.DLL when the following function is called:
OpenCascade original sample AISSelect is not crashed, but the selection does not work correctly.
Anybody knows how to solve the problem?
Any recomendations are very wellcomed.

Paul Jimenez's picture

It's known that OpenCASCADE has issues with incomplete/mediocre/buggy implementations of OpenGL, most likely due to OpenCASCADE itself. Some people have already pointed to different pieces of code that are not correct, still they work most of the time because the OpenGL implementation surely ignores them. I've experimented with both Intel and SiS, and their OpenGL implementation sucks. What you can try instead, although it's not very fast (software emulation), is to use Mesa3D's DLLs instead of the system's OpenGL ones. Just put the 3 main DLLs along with your TKOpenGL.DLL to override the system's implementation when that DLL is loaded. See if at least that way it works.

You may want to search the forums for OCCPATCH. You should find many posts discussing different issues and solutions.