Digital Foundry Article Technical Discussion Archive [2011]

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Yeah, if you look at dem legs in this screenshot it looks like they mucked up the MSAA swizzle that happens in edram. A lot of edges in this shot are very messy when they shouldn't be. Wonder how that made it through QA.

Yeah that's pretty bad...it might be that whatever metric they use for determining edge pixels (for subsample resolve during the deferred pass) is busted on the legs. That combined with the pre-tonemap resolve makes for some pretty poor results.
 
Yeah, the small details in the background really are a problem with MLAA... but actually... I still find it better than only 2xAA or QAA.
MLAA is great for close & gross details more than 4xmsaa but msaa too has almost the same problems of shimmering with deferred & even jaggies too so.... honestly I can't see this marginal advantage of 4xmsaa in shift 2... by the way, forgive my ot but never understood why DF go so frequently down in the final comment about 'better version' or 'version to go', ... it isn't better leave the final conclusion to the readers especially when the differences are so ridicolous?
 
Epic fail in Firefox too; it shows the large image downscaled whenever I advance to the next, and the menu bar on the left side with the Eurogamer stuff is always on top of the image too. They really should fix it...

Yea, I always give up browsing through screenshot galleries on Eurogamer, for the DF face offf galleries they should just have them linked to the actual image files like they are in the artice itself.

They say it's fully deferred..would that be a cause? Also deferred rendering, 720p, 4xMSAA on 360...the first of it's kind?

Are we sure it's fully deferred? That's quite an achievement on 360 then. Especially with the huge 720p 4xMSAA framebuffer.
 
I think MLAA causing shimmering is a bit over exaggerated, every time a game use MLAA, ppl seems to say that it causes all the shimmering in the game. I think a lot of them are specular map aliasing even if those games use standard MSAA. Take Riddick for example, 360 version is using 4XMSAA if I remember correctly and the game has tons of shimmering and aliasing.
 
I think MLAA causing shimmering is a bit over exaggerated, every time a game use MLAA, ppl seems to say that it causes all the shimmering in the game. I think a lot of them are specular map aliasing even if those games use standard MSAA. Take Riddick for example, 360 version is using 4XMSAA if I remember correctly and the game has tons of shimmering and aliasing.
That was most ilkely shader aliasing and not something that MSAA can do anything about.
 
I think MLAA causing shimmering is a bit over exaggerated, every time a game use MLAA, ppl seems to say that it causes all the shimmering in the game. I think a lot of them are specular map aliasing even if those games use standard MSAA. Take Riddick for example, 360 version is using 4XMSAA if I remember correctly and the game has tons of shimmering and aliasing.

I concur. Probably the worst scenario of MLAA was kz3 from my memory, but imho seem more bad/strange implementation than other...
 
Do keep in mind they were shading double the samples in KZ2. I'd hardly say MLAA was poorly implemented in KZ3.
 
Do keep in mind they were shading double the samples in KZ2. I'd hardly say MLAA was poorly implemented in KZ3.
I'm not talking of poorly but bad implemented in different situations... (for example, the bizzare decision to use a dynamic/shaking move camera even when you don't move the character, MLAA not working in repetitive & slow shaking, at least use a TAA combined with it, or eliminate that setting? crysis 2 not shows this problem although TAA is a lot worse of MLAA in motion)
 
I'm not talking of poorly but bad implemented in different situations... (for example, the bizzare decision to use a dynamic/shaking move camera even when you don't move the character, MLAA not working in repetitive & slow shaking, at least use a TAA combined with it, or eliminate that setting? crysis 2 not shows this problem although TAA is a lot worse of MLAA in motion)

not sure what you mean but I have to say I want TAA to stay away from every game possible. Even playing C2 on higher res and frame rate on PC, it can be nasty at time.
 
not sure what you mean but I have to say I want TAA to stay away from every game possible. Even playing C2 on higher res and frame rate on PC, it can be nasty at time.

MLAA has different limits: fine long edge, cross edges & slow camera motions... kz3 use a dynamic 'shake' view even when not move the controller & MLAA destroy everything in this situation... probably combined with TAA this limit could be masked better... or just eliminating this camera 'effect' setting, at least in the worst scenario....
 
Ah... fair enough. It does become tedious though to tell the artists what not to do because of the AA solution. :p In the end though, it's just a trade-off between RSX<->Cell. It's a bit unfair to say that the algorithm is poorly implemented (implying a difference in the coding) when it's really the game content isn't as well suited towards it.

In that sense, God of War 3 seems like the perfect candidate with distant & relatively stable camera views and little if any thin objects.

And take DLAA, for instance, which works well for Star Wars, but probably wouldn't look too good for games with very detailed texture work.
 
Ah... fair enough. It does become tedious though to tell the artists what not to do because of the AA solution. :p In the end though, it's just a trade-off between RSX<->Cell. It's a bit unfair to say that the algorithm is poorly implemented (implying a difference in the coding) when it's really the game content isn't as well suited towards it.

In that sense, God of War 3 seems like the perfect candidate with distant & relatively stable camera views and little if any thin objects.

And take DLAA, for instance, which works well for Star Wars, but probably wouldn't look too good for games with very detailed texture work.
I hope to not appears too much arrogant, but I have the big suspect that guerrilla not knowing the MLAA 'limits' when they have implemented or probably they have noticed that too late... for example, for the fences they have used a simple texture pop in in the long distance. My question is: how much cost 2xaa limited to some edges, I'm not talking of MSAA but single simple of AA, I don't know if I'm enough clear. Pretty interested to see MLAA+2xAA in some ps3 game, obviously cosidering its limits.
 
It may be that MLAA wasn't planned for from the start.

Introducing something like a new AA technique mid way through development could leave you with issues that it isn't possible to address within your budget and schedule, but because you have the CPU time to spare, and because the net result is a win (even with some issues) you go for it anyway.
 
DF twitter- "Tomorrow on Digital Foundry: the Making of Crysis 2 - extensive discussion with the technical architects of CryEngine 3."
 
The Making of Crysis 2

Edit: Really awesome stuff, great work grandmaster :)

"GPU side, when programmed properly, they are fairly similar. We just have to be conscious of the clear handicap on PS3 RSX in terms of vertex processing, but other than that, on fragment processing side they are relatively similar, both have their strengths but such differences become irrelevant in the long run, especially when compared to PC platforms,"

"The SPUs do indeed allow for easing the workload for the RSX. We decided not to go too crazy in this direction as it requires render targets and assets to reside in main memory. We are able to run skinning for example on SPUs as well, but we could not afford the additional memory required in the end.
It is possible to use the SPUs to support deferred shading, run post-process effects and do triangle culling. But again, it all requires main memory we did not have as our levels are fairly large compared to other games and our SPUs were in fact pretty loaded with particles, animations, physics, low-level rendering and culling already."


"The 1152x720 resolution on 360 simply allows you to maximize eDRAM usage on a deferred lighting engine without having to resort to tiled rendering.
On the PS3, due to the extremely limited system memory we resorted to downloading memory into video memory.
We bumped into severe video memory limitations, so it was a good compromise to save a big chunk of video memory for other usages. Plus, while on consoles we are CPU-bound during combat due to physics, AI, etc, on less intensive situations on the PS3 we are GPU-bound, so the additional quick 10 per cent performance gain was also very welcome."

GI:

"On consoles all milliseconds and memory counts, so at end of this project we made the tough decision to disable it for consoles. We still have a very simple and coarse GI approximation on consoles, where our art department fully controls the look, meaning we pay couple of milliseconds on areas where it is actually making a significant visual contribution."



So game is processing graphics mostly on RSX, and Cell is used for "standard CPU stuff" - and still, PS3 version is good, much better than most multiplatform releases. That's impressive :)
 
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He makes it sound like they didn't have time to do everything they wanted to do, which makes sense. I'd like the see what they can achieve in the future :smile:

Really nice interview, though. It's great that they're finally starting to open up a bit.
 
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