Faster redraws

I am looking for a faster way to do simple screen exposes - I’ve got a complicated rendering that the user can manipulate in 3D so the whole thing is massively display listed, but for simple window expose events I thought it might be faster to save off the front buffer using glReadPixels() and writing it back after the expose. Is this going to give me any savings, or whould I be looking elsewhere for the solution?


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