title: Difference between glBitmap and glTexImage2D
body: <p>I need to display image in openGL window.<br>
  Image changes every timer tick.<br>
  I've checked on google how, and as I can see it can be done using or <em>glBitmap</em> or <em>glTexImage2D</em> functions.<br>
  What is the difference between them?</p>