The Game Technology discussion thread *Read first post before posting*

[Shifty Geezer]

I take it your post is very offensive to me but hey what can I do?

I don't think he intended to offend. If you do drive, you could just say so!

Didn't the pic I posted have a camera outside the car?
Check this out for a realistic comparison

You're picture has the grandstand as black as the windows. The contrast is so high in that image it's impossible to see what's going on with the engine. Given the viewing angle, gradient of the rear window, and contrast, that picture is far from conclusive. You really want an image from lower down which would show transparency more effectively.

 

[marcus_rocks]

I don't think he intended to offend. If you do drive, you could just say so!

You're picture has the grandstand as black as the windows. The contrast is so high in that image it's impossible to see what's going on with the engine. Given the viewing angle, gradient of the rear window, and contrast, that picture is far from conclusive. You really want an image from lower down which would show transparency more effectively.

I do drive Shifty, I drive 50 miles a day. And I do see through other car's rear window and saw drivers using cellphones all the times.
The grandstand is in the shadow, it sure must be black. The pix he posted were taken during sunset, where visibility is low. I think we can't use those pix. Besides, it is not nice to post somebody's car's license plates online.

 

[joker454]

I would like to know the resolution you are referring to. I remember you said GT5P uses full-res for the smoke and dust and the reason for it was that there were not a lot of them. Is it different now or the same?

Did i really say that? I don't remember claiming that but if I did then I was wrong, I'd never expect GT5p to use full res for smoke or dust, or any PS3 game to do that for that matter. Full res is a bad idea for 30fps games, a very bad idea for 60fps games, an extremely bad idea for 60fps games like GT5p that might suddenly have a need to kick up lots of smoke or dust if a bunch of cars spin out, and a horrifically bad idea if it does all previously mentioned and must also render at 1280x1080.

Aside from launch titles, I don't know of any PS3 games that still uses full res for low detail transparencies. Certainly all the 1st and 2nd parties don't go full res, just look at Killzone, Uncharted, Infamous, Resistance, Ratchet, MGS4, etc... Some hide it better than others, it's probably hardest to spot in Killzone, and easiest to spot in Ratchet.

 

[Shifty Geezer]

The grandstand is in the shadow, it sure must be black.

Well that's kinda the problem. Inside the car is also in shadow, so it too should be black, no? The problem here, regards seeing clearly, is the specular reflection on the road and correctly exposed sky are creating too much contrast, and the tone-mapping of the HDR seems to be matching a camera's rather than compressing the dynamic range to favour the mid-range. Rotmm's photo's have similar contrast issues, an inherent problem in photographing cars with a big sky behind them. Images that show the "dark window" sundrome need to have less contrast.

I found the image on DF are definitely blacker than most cars. The Mini's are clearly tinted glass. Although again, this could be an issue of tone-mapping, underexposing the shadowed areas. Watching the third video, crashing, at DF has some better views, and the windows don't look too tinted there, with a clear view through two windows to the grass beyond etc. The interiors do look very dark, but the style of that vid and Forza 3 in general is heavy on the contrast. I don't know if that's a technical decision to hide low-quality assets or a purely artistic decision though. Knowing the hardware, and with what Joker is saying, I remain unconvinced that they are limiting transparency draw through the glass.

 

[marcus_rocks]

Well that's kinda the problem. Inside the car is also in shadow, so it too should be black, no? The problem here, regards seeing clearly, is the specular reflection on the road and correctly exposed sky are creating too much contrast, and the tone-mapping of the HDR seems to be matching a camera's rather than compressing the dynamic range to favour the mid-range. Rotmm's photo's have similar contrast issues, an inherent problem in photographing cars with a big sky behind them. Images that show the "dark window" sundrome need to have less contrast.

I found the image on DF are definitely blacker than most cars. The Mini's are clearly tinted glass. Although again, this could be an issue of tone-mapping, underexposing the shadowed areas. Watching the third video, crashing, at DF has some better views, and the windows don't look too tinted there, with a clear view through two windows to the grass beyond etc. The interiors do look very dark, but the style of that vid and Forza 3 in general is heavy on the contrast. I don't know if that's a technical decision to hide low-quality assets or a purely artistic decision though. Knowing the hardware, and with what Joker is saying, I remain unconvinced that they are limiting transparency draw through the glass.

They are two different things. The car front is facing the sun (look at the shadow of the car), thus sunlight must go through the windshield. no? The grandstand is not facing the direct sunlight thus in the shadow.

Did i really say that? I don't remember claiming that but if I did then I was wrong, I'd never expect GT5p to use full res for smoke or dust, or any PS3 game to do that for that matter. Full res is a bad idea for 30fps games, a very bad idea for 60fps games, an extremely bad idea for 60fps games like GT5p that might suddenly have a need to kick up lots of smoke or dust if a bunch of cars spin out, and a horrifically bad idea if it does all previously mentioned and must also render at 1280x1080.

Would you tell me the resolution of the smoke and dust? From my personal observation, I would tell that Killzone 2, U2 uses lower res for smoke effects but not GT5P. The experience I had when I first played the demo was this: really? I can almost see individual particles when the car drove in the sand. That just wowed me and I would stand by the fact the GT5P uses full-res for the smoke effects until proven otherwise.

 

[Silent_Buddha]

Oh, I'm sure Naughty Dog are (and SSAO is probably one of the good uses they have for them, heh) but I was talking more in regards to your average third party developer here, who one would expect not to be on quite the same level as Naughty Dog or Guerilla games when it comes to making good use of the SPUs. What are the restrictions on that 6th core then? Would reserving 6ms in a 30fps title (i.e. around ~20% of resources) for SSAO be too much? If so, then yeah that changes things and it definitely makes that performance figure become less attractive. Now, if only developers had full access to the proper 8 SPU chip.............

The thing about 3rd party devs however, is that they are extremely unlikely to leverage a process on one console or the other if it means porting their game will be difficult or result in drastically differnt visuals. There are some exceptions of course.

Regards,
SB

 

[MazingerDUDE]

Aside from launch titles, I don't know of any PS3 games that still uses full res for low detail transparencies.

Ninja Gaiden Sigma 1 & 2 use full res alpha, and they are both 60 fps games

From what I've seen in demo, FF13 also uses full res transparencies.

 

[Rotmm]

The pix he posted were taken during sunset, where visibility is low. I think we can't use those pix. Besides, it is not nice to post somebody's car's license plates online.

The pix I posted were taken between 1:30 and 2pm. And yes, the sun is fairly low at this time of year, but certainly not "sunset". However, if you look at the length of the shadow on the cars in my pix, and the one in the DF grab you posted, then it's clear that the virtual shadow shows the sun is even lower on that track.

Oh, and if you really do drive 50 miles a day then you'd more than understand that your ability to see if the driver in front of you is on the phone is very much dependent on the tinting of his rear window, the angle that the glass is slanted at, the angle of the sun, cloud cover and even the fact that you are looking at a even plane and are not (as in the pic you posted) floating 6ft above the car looking down into it.

And just in case you were in any doubt and still hold onto the idea that "[Forza 3] uses lower resolution buffer for the transparent objects and it uses dark colors to hide the details of the car's interior" then I have a small adjustement which shows that the engine is rendering (and not hiding) the inside of the car. Unfortunately, the original image has been heavily jpeg compressed, and also note there are reflections on the window to contend with, but:

Original (500%)

Adjusted (500%)

Hope this helps.

 

[Arwin]

Is it possible that use of HDR in Forza 3 is what is causing issues with overdraw/transparency?

Also, I feel that the cockpit and maybe the full car interior is not rendered using HDR. At least I haven't yet seen anything in Forza 3 like the bright sunlight that can strike the interior of a car in GT5 Prologue, and I think it is one of the reasons why the interior in Forza 3's cockpits look so bland.

 

[Alucardx23]

I have Forza 3 and the reason the windows are blacker than normal is because of the lower detail model for the car interior that is used during the race, you can use the photo mode and move the camera to see the difference when the car is in the track and when it is in the car selection screen. I guess they just want to hide the low res textures used during the race, but yes compared to GT5 Prologue, the Forza 3 cars take a bigger hit in detail when they are in the race.

 

[assurdum]

GT5p does not have an abundance of transparencies, it has very few actually, totally typical of a PS3 game. See through rear windows are very little transparency, and their dust particles are the typical no detail low res stuff all PS3 games do (see the new Ratchet demo of R&C for another example of obvious low res transparency buffers). The rest of the game is all very overdraw predictable.

The cost of msaa is on a per primitive basis, and GT5p has the typical stripped down 60fps console environment that would make 4xmsaa doable. The cars in GT5p look great, but everything else just screams 60fps compromise.

Low buffer and very little transparency in gt5p? Reading & watching DF analyzes not seems so...imho.

 

[AlNom]

Low buffer and very little transparency in gt5p? Reading & watching DF analyzes not seems so...imho.

The article is relating the two games. In the grand scheme, it's not that much.

 

[assurdum]

The article is relating the two games. In the grand scheme, it's not that much.

He talking of transparencies differences however.
P.S.
However games with full res buffers on the ps3 exists. Rare but exists (ngs & ngs 2 yet posted). Cryengine 3 too seems use these. Burnout use too or not? (my question, I haven't noticed).

 

[joker454]

Would you tell me the resolution of the smoke and dust? From my personal observation, I would tell that Killzone 2, U2 uses lower res for smoke effects but not GT5P. The experience I had when I first played the demo was this: really? I can almost see individual particles when the car drove in the sand. That just wowed me and I would stand by the fact the GT5P uses full-res for the smoke effects until proven otherwise.

I'll check it again once GT5 comes out, I don't have GT5p handy. It's easy to miss low res buffers though, for some stuff it's just really hard to tell. I'd be shocked if any studio still did smoke at full res on PS3, that's a mistake. 1/2, 1/4, 1/8 and 1/16 are all better options. It's possible GT5p does a mix, like kick up full rez opaque particle bits mixed with reduced res transparent dust. It's all about deception in the end, whatever works to meet performance goals.

Ninja Gaiden Sigma 1 & 2 use full res alpha, and they are both 60 fps games

From what I've seen in demo, FF13 also uses full res transparencies.

Then they are leaving performance on the table. The first thing an outside PS3 tech analyst would tell them is to drop the res. Too much full res transparency would stand out like a sore thumb on a gpad performance grab.

 

[assurdum]

Then they are leaving performance on the table. The first thing an outside PS3 tech analyst would tell them is to drop the res. Too much full res transparency would stand out like a sore thumb on a gpad performance grab.

I don't understand this scepticism... nothing of personal, big respect, but when we talking of 360 & tiling or others limits, it is 'pretty easy to avoid the problem', 'just depending of the developer', etc etc & ok, me too I think so. When we talking of the ps3 and its limits follow a lot of 'no way', 'impossible', 'not exists'. I think could exist different way to avoid the gap of the bandwith...said 'absolutely no' because theoritically the bandwith is everything for high buffers, it is right for the 'theory'. But in the development you could to find so different ways, even something we can to define theoritically impossible imho.

 

[MazingerDUDE]

Then they are leaving performance on the table. The first thing an outside PS3 tech analyst would tell them is to drop the res. Too much full res transparency would stand out like a sore thumb on a gpad performance grab.

Indeed, when there are like 3 simultaneous explosions, the game will freeze for about 10 frames or so. It's not game breaking, though it would cause some serious problems in games with some constant explosions like shooters. However I do feel that the low res transparencies are kinda over used since I see them so often even in the scenes with nothing much going on. I wish they'd at least filter them like they did in KZ2, seeing huge jaggies caused by low res alpha is rather unpleasant.

 

[ihamoitc2005]

GT5p does not have an abundance of transparencies, it has very few actually,

My friend, it has much more transparency than Forza 3.

See through rear windows are very little transparency

I can see very well through the rear window.

and their dust particles are the typical no detail low res stuff all PS3 games do

I am sorry to disagree again. I feel the particles are much better than most games. Very crisp.

Real Drift Video:
http://www.youtube.com/watch?v=HYdqnlqpRWs&feature=related

GT5 Prologue Drift Video (You can see great smoke and also transparency):
http://www.youtube.com/watch?v=Xw3ECmudAlI

Forza 3 Drift Video:
http://www.youtube.com/watch?v=cF03QdhKr5o

The rest of the game is all very overdraw predictable.

Actually, again I must disagree. For example, in the picture with the ferris wheel, you can see in GT5 the color of the sky through each ferris wheel passenger box but in Forza 3 you cannot.

I feel both GT5 Prologue and Forza 3 are over-draw "unpredictable."

The cost of msaa is on a per primitive basis, and GT5p has the typical stripped down 60fps console environment that would make 4xmsaa doable. The cars in GT5p look great, but everything else just screams 60fps compromise.

No more than any other console game that I have seen my friend. That is the problem with hardware that cannot change for many years.

Still, the only parts that look bad are the trees. Everything else has enough detail. Lots of pedestrians and London is amazing with details and also let us not forget 16 cars.

I doubt Forza3 tinted the rear glass because of transparency limitations, they must be hitting some other limitation.

This game has very little or no transparencies. You must see the game to realize this. Even basic things like dust is a problem for this game.

maybe they are using the alpha channel for something other than alpha.

This will be my guess also. I have not seen another modern game with so little transparency. Maybe they are trying to squeeze blood from the stone.

In the end there might be a more obvious answer to all of this. PD has been making car games forever, they might just be better at it. For example I'd wager that PD's vehicle shaders are smarter (ie, less cycles) than Turn 10's.

When GT5 Prologue is released, PD only has only maybe 2 years experience on PC GPUs like Nvidia RSX. Before that they make games on super-multi-pass PS2 architecture which is a very different rendering concept.

So it is more sensible to say Forza 3 has much smarter shaders because they have been making directx type shader games for many more years than PD.

In the end though you can't get blood from a stone. Msaa and transparencies are two weak points on PS3 hardware that have to be designed around, and PD did just that.

A Digital Foundry frame-rate analysis of GT5 Prologue while driving circles on the sand will be very interesting to see.

GT5 is a beautiful game: http://www.youtube.com/watch?v=H54Y5SXpCC4&feature=related

 

[joker454]

I can see very well through the rear window.

I think you misunderstood, I meant the amount of overdraw from see through rear windows is very little in the grand scheme of things.

I feel both GT5 Prologue and Forza 3 are over-draw "unpredictable."

Aside from kicked up smoke and dust, they are two of the most predictable overdraw games out there.

No more than any other console game that I have seen my friend. That is the problem with hardware that cannot change for many years.

Not quite, it got solved in 2005 on console with the 360 It does not have the per primitive AA cost that PS3 does, that part is actually free on 360. Ok...strictly speaking it's not, as in if your lod system draws tons of tiny triangles that take up one pixel then there will be a cost. But realistically speaking, it's free. Now tiling on the other hand, not so free.

Still, the only parts that look bad are the trees. Everything else has enough detail. Lots of pedestrians and London is amazing with details and also let us not forget 16 cars.

Pedestrians are easy, been there done that. 16 cars is cool though. I'm curious why Forza stuck to 8, it had to be either vertex or cpu related, but I'm guessing they ran out of cpu.

This game has very little or no transparencies. You must see the game to realize this. Even basic things like dust is a problem for this game.

Both of them have very little transparency, it's one of the things that makes both games seem sterile to me and hence why I would have preferred that they both just went for 30fps. But that's just me, I know that's not a popular option

When GT5 Prologue is released, PD only has only maybe 2 years experience on PC GPUs like Nvidia RSX. Before that they make games on super-multi-pass PS2 architecture which is a very different rendering concept.

So it is more sensible to say Forza 3 has much smarter shaders because they have been making directx type shader games for many more years than PD.

Don't think of it in terms of hardware, DirectX or stuff like that, think of it in terms of the shaders themselves. How you light stuff takes skill beyond what the hardware and render engines offer, it takes years of experience to learn what works best, then you just apply it to the hardware dujour. PD simply has more experience.

 

[Alucardx23]

Originally Posted by joker454
Pedestrians are easy, been there done that. 16 cars is cool though. I'm curious why Forza stuck to 8, it had to be either vertex or cpu related, but I'm guessing they ran out of cpu.

When you say CPU what are you referring? Physics calculations? There are other games that have more than 8 cars on 360, Need for Speed Shift for example supports up to 16 cars all of them starting the race at the same time, but Need for Speed is 30fps so I guess is easier to have more cars, but my question is what does that have to do with the CPU.

 

[ihamoitc2005]

I think you misunderstood, I meant the amount of overdraw from see through rear windows is very little in the grand scheme of things.

I will be honest my friend. I feel you have not played this game yet. I will suggest it because it is a good purchase.

You can see great over-draw in this gameplay video. View through the rear window is very clear (even for enemy cars). You can see clearly full lighting and shadows for all interior surfaces with also reflection on the glass. In cockpit view, when you look out, on top of this you can even get too much smoke from the front car.

This game has much over-draw.

http://www.youtube.com/watch?v=HWqX5on9oNY&feature=related

Aside from kicked up smoke and dust, they are two of the most predictable overdraw games out there.

I must disagree respectfully on this. Xbox360 is supposed to have great over-draw but Forza 3 has very little over-draw. PS3 is supposed to have trouble with over-draw but GT5 has great transparency and smoke as you can see in the real-time 60fps gameplay video.

You can even see the interior lighting and shadows for the enemy car in the rear view mirror! Very surprising!

That is why I must continue to say they are two of the most unpredictable overdraw games out there.

Not quite, it got solved in 2005 on console with the 360 It does not have the per primitive AA cost that PS3 does, that part is actually free on 360. Ok...strictly speaking it's not, as in if your lod system draws tons of tiny triangles that take up one pixel then there will be a cost. But realistically speaking, it's free. Now tiling on the other hand, not so free.

I think this is a more complicated issue than that plus what is most important is net results. What we can see is that when seeing total effect of various parts of rendering system , at 720P, the 360 has significant primitive based AA cost, ie., once you have AA @ 720P, primitive cost is greater than 1:1 and with more AA, cost increase is exponentiallish.

Pedestrians are easy, been there done that.

We disagree too much my friend. lol I know your game has many pedestrians/spectators but Forza 3 has reduced pedestrians/spectators than Forza 2. Why cut back unless it is for performance?

16 cars is cool though. I'm curious why Forza stuck to 8, it had to be either vertex or cpu related, but I'm guessing they ran out of cpu.

Maybe both my friend. Else why have low LOD models for gameplay and high LOD models for photomode? If vertex is not an issue then why not use high LOD all the time and also render all interior objects with high detail and full lighting/shadow? Even the camera lens in Forza 3 is to have faster LOD transitions. There must be a reason but I do not know what exactly.

I don't think it is a memory issue since 360 has little bit more available memory than the PS3 yet GT5P can have double. I remember PD chief said GT4 has a very efficient method for story car data and they use this in GT HD. Maybe they use this system in GT5 Prologue, maybe not, but somehow they have double cars with (looks like) double detail.

I would have preferred that they both just went for 30fps. But that's just me, I know that's not a popular option

I am happy with 60fps my friend. GT5 Prologue is really amazing. Did you see the new Tokyo track? Even the trees are better.

Don't think of it in terms of hardware, DirectX or stuff like that, think of it in terms of the shaders themselves. How you light stuff takes skill beyond what the hardware and render engines offer, it takes years of experience to learn what works best, then you just apply it to the hardware dujour. PD simply has more experience.

I mentioned Directx because you mentioned PD maybe has more efficient shaders. This kind of shader that runs on RSX is very different concept than super-multi pass lighting of PS2 hardware. Forza 3 developers have been using this kind of shader and I am sure have developed many tricks to reduce shader cycles to get the effect they want.

So I feel PD has much more learning curve than Microsoft/Turn10 for this kind of system. Maybe this is also why some feel Japanese developers are behind the technology curves. Maybe they still think of PS2 style rendering with many polygon, layering and multiple passes but American developers who make PC games for many years are used to more complex shaders with few passes.

Plus, Digital Foundry writes that GT5 Prologue has more sophisticated (looking) shaders and more effects at 50% more resolution with 2xAA with much more over-draw situations (interior rendering, smoke, dust).

Maybe even stones have blood.