title: Clearing the color buffer in OpenGL
body: <p>I am developing an iPhone app that uses OpenGL ES to draw the graphics onscreen. With each new frame i draw to the entire screen, which brings me to my question. Is it necessary to call glClear to clear the color buffer each frame or can i just overwrite it with the new data? The glClear function is currently 9.9% of the frametime so if i could get rid of it it would provide a nice boost. </p>
  
  <p>Forgive me if this is a very naive question as i am something of a noob on the topic. Thanks in advance.</p>