title: OpenGL ES2.0 glReadPixels() is very slow
body: <p>I am using glReadPixels to read the pixels from FBO to memory.</p>
  
  <p>Here is the code:</p>
  
  <pre><code>UINT8* data;
  glBindFramebuffer(GL_FRAMEBUFFER, FBOID);
  glReadPixels(0, 0, w, h, GL_RGB, GL_UNSIGNED_BYTE, data);
  </code></pre>
  
  <p>I found this operation is very very slow...  Is there any alternative in openGL ES2.0(Android)?</p>