title: Optimization using a lookup table:
body: <p>This guy: <a href="http://andrew-hoyer.com/experiments/cloth/" rel="nofollow">http://andrew-hoyer.com/experiments/cloth/</a> made a javascript algorithm to simulate a cloth. He pointed out the code was too slow so he had to optimize square roots using the taylor series.</p>
  
  <ol>
  <li><p>Couldn't this be optimized instead by pre-calculing every possible value and using a lookup table to get it?</p></li>
  <li><p>Is this often used? For instance, on 3d games, do they actually perform the calculations or they already have a lookup table for every sin, cos, tg, sqrt and similar functions?</p></li>
  <li><p>Why isn't this pre-programmed into processors? </p></li>
  </ol>