title: WebGL: Prevent color buffer from being cleared
body: <p>Even if I remove </p>
  
  <pre><code>gl.clearColor(c[0],c[1],c[2],1.0);
  gl.clear(gl.COLOR_BUFFER_BIT );
  </code></pre>
  
  <p>the screen still gets cleared at the beginning of the
  next draw cycle. Is there a way to prevent this.
  I´d like to achive some kind of overpaint effect.</p>