               +-----+-------+------+--------------+
               | Red | Green | Blue |    Alpha     |
+--------------+-----+-------+------+--------------+
| buffer 0     |   diffuse (RGB)    | specular (R) |
+--------------+--------------------+--------------+
| buffer 1     |   normal (XYZ)     | specular (G) |
+--------------+--------------------+--------------+
| buffer 2     |   ambient (RGB)    | specular (B) |
+--------------+--------------------+--------------+
| depth buffer |      depth and stencil value      |
+--------------+-----------------------------------+