title: Assign integer values to color in opengl es 2.0
body: <p>i need to set color by byte type or integer,  not float values. 
  How can i assign this type into <code>gl_FragColor</code>? 
  Dividing the value by 256 wont give me the wanted precision. 
  My main purpose is to know the specific value of each bit in the color buffer,  if i draw line only with specific color.
  for example i want that in the color buffer at the red value of pixel only 2 lsbits will be on,  what color value should i transfer to <code>gl_FragColor</code>? 
  If i had an option to write byte type values,  i would write the value 3 to red component
  Thanks</p>