Hi,
I’m getting different results, actually bugs, between Full Acceleration and No Acceleration on my M$ win98 machine. For example, when I gluUnProject the results with no acceleration are correct but when I use full acceleration I get drastically wrong results.
This is what the feature is for. It’s obviously a bug in the hardware driver. When you dial down to no acceleration you effectively use a ‘safe’ software OpenGL implementation.
Simply enumerate the available pixel formats and choose one that is not accelerated.
I posted some code enabling you to just do that a while ago. Search the forums for posts from me (use the Exact Name search, it’s faster !) with the keyword “software”.