Iniquity auf [URL="http://www.forumplanet.com/planetelderscrolls/topic.asp?fid=16709&tid=1867260" schrieb:
Planetelderscrolls[/URL]]Here's some more information:
What AA you can use with HDR is actually determined by the program that's using it. Older, less-advanced games using HDR, from Far Cry to Splinter Cell 3 to Serious Sam 2 use a version of HDR called OpenEXR; the game developers didn't actually make it, they licensed it from Industrial Light & Magic, which as you're probably aware, makes CG and other effects for use in movies. (their first break, of course, being Star Wars)
OpenEXR is a rather easy to implement version, but it was designed for CG movies, not video games. As a result, it is incredibly rutheless when it comes to power drain, and it's incompatible with MSAA, (multi-sample-anti-aliasing) the AA method used in modern games. CG Movies use SSAA (super-sample-anti-aliasing) which more closely mimics real life, but hjas hardly any improvement for its cost; using x4 SSAA cuts your framerate by 75%, and x16 SSAA cuts it by 93.5%, and it increases from there. Since CG movies aren't done in real-time, this isn't a problem. (on average, each single FRAME from a movie takes a massive "render farm" of thousands of computers about 1-2 hours to draw)
However, since games have to be done in real-time; preferably, each frame has to be drawn using much less hardware, and be done in hopefuly, less than 33 milliseconds. (enough to yield 30fps) That's why MSAA is used instead of SSAA.
Normally, NO card can run MSAA and OpenEXR at the same time, though ATi made an exception with their X1k series; it was a work-around they implemented in their cards. With other cards, such as GeForce 6 and 7-series cards, you can only use SSAA, which is actually available at one setting: x4. This will cause a serious hit to your framerate, but it will be AA.
Fortunately, Oblivion isn't using OpenEXR. Rather, since OpenEXR wasn't first availible to developers until very early 2005, (and games like Splinter Cell 3 added it in at the last minute) and BethSoft had decided to use HDR since they started in 2002, they made their own HDR program, that's COMPLETELY different.
This is good; it's everything that OpenEXR isn't; whilt it's still something that hurts performance, it's a lighter hit than any other form of HDR known. Also, it can be used on cards that don't support SM 3.0, though the older, SM 2.0 version, (for Radeon 9, X, and GeForce FX 5 cards) does cause a bigger performance hit.
There's only one flaw that's known of, though; when using it, some forms of blending become prohibitively expensive to use. As a result, it seems that using HDR will disable these blending acts, such as alpha-blending. In Morrowind, this was used to make the edges of trees look smooth even if you weren't using AA. Losing this is really no big deal, since it doesn't work correctly in all programs aside from Morrowind. This is also what "transparency AA" is used to correct. Even if you can't correct it, it's still hardly noticable, particularly at distance, so it's nothing to worry about.
(Quote from Nottheking)
