title: What are good techniques for high performance full screen bit-blitting on iOS?
body: <p>Assume I want to program a <a href="http://www.youtube.com/watch?v=4s8MRcUwpB0" rel="noreferrer">Star Field</a> animation. Not by using OpenGL but by drawing directly to the screen buffer or to off-screen buffers that can be placed on screen.</p>
  
  <p>That Star Field demo running on the TRS-80 is of course just an example. Think video decoding or full-screen animations as other possibilities where rates of 20+ frames per second are needed.</p>
  
  <p>What are good techniques for doing this? I am interested in both official and private API implementations.</p>
  
  <p>If you can, please show some basic code.</p>