Thank you, Kornel, I appreciate your insights. We have progressed a fair bit since my post above to see that you are right on the money. We've had OpenGL-based code working for about a week now. We haven't had to put any driver-specific decisions in the code yet, though I'll keep in mind what you have said about prompting the user to update to driver versions that work. I noticed over on the Microsoft forum the advice given again and again (not to mention the Photoshop Windows forum) is to UPDATE YOUR VIDEO DRIVERS. Wow, what a state of flux in this realm! You'd think it would be more consistent, given that some form of OpenGL has been around for quite a long while. So far I'm having quite good luck running OpenGL in a separate thread from the UI, mostly by being VERY careful to keep the GDI from doing anything at all to the window, which is a picture control at its heart. Today we finished our color space management logic, so we're displaying the proper colors no matter what profiles the user is using and has set for the monitor. That was fun. The clear advantage of having the power of GPU acceleration is certainly worth the pain of going down this road as far as I can see. My ATI card really blasts through thousands of OpenGL commands in an eyeblink, especially using display lists! My window updates on changes of the controls are organically smooth now. It is kind of a shame, though, that the environment isn't more consistent from machine to machine. Finding the right "fudge factors" to get things to come out on exactly the right pixels is more than trivial. You wouldn't think just drawing a 1 pixel border around something should be challenging. One specific question for you, if you're willing: Have you any experience running OpenGL in an off-screen buffer? I'm wondering if cordoning it off from the actual display and managing the bits at the interface through normal GDI BitBlt operations would help open up additional possibilities to do the multi-buffering and flicker reduction that I have been doing in the past during dialog resizing... -Noel
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