Finally after the wide acceptance of FBO in most hardware i decided to switch my aging shadow map generation code using FBO (i was using p-buffers earlier which was nothing short of being a pain in the neck). Everything worked fine for spot lights and i saw a great performance improvement. However for omni lights (i use cube maps for omni lights) 4 of the faces of the cube map gave proper shadow map whereas the last 2 (in my case pos z and neg z) came out all black. I was using one FBO and attaching the sides of the cube to different color attachments. I rendered to different faces by setting the draw buffer using glDrawBuffer(...) call. If i use 6 different FBO's the result is correct so there is nothing wrong with my shadow mapping code (it has been tested thoroughly anyways). What i was able to deduce, after performing further tests was that my current hardware (GFX 5700 Ultra, 78.01) doesn't support more than 4 color attachments in FBOs and that's the reason why the last 2 attachments of the cube always came out all black. Is this a limitation of the hardware or a driver issue? Secondly is there any glGet...(...) call via which i can determine the number of color attachments that a particular hardware can support for one FBO?
Thanks in advance.