1) I'm creating a CAD like application. A single scene rendering might contains hundreds of thousands of lines and cannot be drawn in realtime when the paint event occurs. What I want to do is rendering to a static buffer, which I can blit/swap to the front buffer when a paint event occurs. The problem with SwapBuffers is that it seems to destroy the contents of the backbuffer, even in windowed mode. What is the best way to work this out?
2) I need some nice xor:ed rubberboxes (for object selection etc.). I can do this by setting GL.DrawBuffer to frontbuffer and GL.LogicOp to xor. However xor mode seems to work only in indexed color mode. Indexed color mode should be ok for me, if it wasnt for that hardware acceleration does not work if color depth is another than the physical screens. This makes indexed mode very slow. Any suggestions on how to use OpenGL to draw nice rubberlines/boxes using opengl?