It doesn't look like ATI will be able to get HDR+AA to work in GRAW, because it uses multiple render targets.
The man who made HDR+AA a reality on ATI's Radeon X1000-series
cards in The Elder Scrolls IV: Oblivion
has surfaced from his secret nuclear bunker again. This time, he's come to chat about Ghost Recon: Advanced Warfighter
The latest addition to the Ghost Recon series makes use of High Dynamic Range (HDR) lighting and lots of special effects. It's also the first game to make full use of AGEIA's PhysX PPU, too.
One difference between the PC and Xbox 360 version is the lack of Anti Aliasing in the PC version - this makes the game less appealing to the eye, as there are many areas of the game where it could really benefit from some Anti Aliasing.
managed to catch up with Chuck while he was on the loose and asked the question that many have been wanting to know the answer to. Can he get HDR and AA to work in Ghost Recon: Advanced Warfighter
in the same way that he did with Oblivion
He starts "The rendering path in G.R.A.W. is very different from most games in that it appears to make extensive use of multiple render targets (MRTs)."
Multiple render targets essentially mean that its possible to render different pixel colour values to different surfaces when only using a single draw operation. A similar method was used in Splinter Cell: Pandora Tomorrow
, albeit with DirectX 8.1.
He goes on to mention that the DirectX 9 specification doesn't allow for multisampled Anti Aliasing in conjunction with multiple render targets, meaning that Anti Aliasing needs to be sampled on all surfaces - this would be incredibly costly. You can read his full answer here
Discuss in the forums.