   framebuffer size
  I have two quick questions:1. Is it necessary or at least better for a framebuffer to have dimensions in powers of 2 (eg 2048x1024 rather than 1280x800)?2. If the framebuffer isn't the same size as the screen, and if I plan to copy the framebuffer to the screen after doing some effects, how do I keep the proportions right, for example text drawn to the screen?   
  1. Generally, no. For render-to-texture effects, maybe (power of 2 textures are slightly faster to sample on some cards).-- Keep in mind though that with your example numbers you're doubling (2.048x) the amount of work the pixel shaders have to do, which probably far outweighs the slight performance benefit of having nicely sized textures.2. Setting the correct aspect ratio (for the screen) in your projection matrices.   ;  Thanks.   