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

I'm sorry guys, I've corrected the first link (It seems I can't edit the message).
You can take a look at it, I've selected the best parts where we can see this effect.

Graham : Casting multiple low res shadows to approximate penumbra is very costly no ?

Not if it's done at low resolution then reprojected. Which is what it looks like to me.. There was some subtle pixelation in places even in the nasty gamespot live stream I watched.
Also it doesn't have to be a traditional shadow using polygonal rendered shadow maps. It could easily be an approximation of the skeleton using ellipsoids, etc.
 
It's difficult to analyse those indirect shadows with that footage alone, but it seems the characters don't cast them into themselves, SSAO does that though -but its hard to tell-
I couldn't spot a any part where there are such kind of shadow being cast from the environment into the characters, still they do have good ambient maps like Unchy3 had, and finally, from the small amount of dynamic geometry in the demo - the moving clothes in the closet, and the furniture on the desk where an enemy's head is smashed into - that didn't look like was casting those shadows either, aside from the SSAO again... Yet, there are instances where the same character casts shadows into different directions simultaneously.
I would bet they are done per character, like many UE games still do today, they are probably pretty low res as it is a little blocky as Graham pointed out. Then they blur the shit out of them, either in texture space or as they are projected into the scene, and they have some sort of distance attenuation, not unlike oldschool Max Payne 2 had. All of that is of course just my speculation, on how I think I would try to do that if wanted to achieve what was shown in the demo. If any of my guesses are true though, they must have some really cool offline tool to bake in the places and the directions these shadows appear with cohesive results.
 
Halo 4: Forge Dynamic Lighting.

So, Forge lighting.

Frankie (The Halo Franchise Director) says the system is called:
Single Probe Spherical Harmonic lighting System


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Here's what I noticed, speculated:

ikHPlO78Gt9aC.gif


The shadows are generated and rendered within a single frame after the player pressed the dpad to enter player mode, so they are most likely rendered each frame in real time like most games these days that have dynamic shadowing. The spherical harmonics took quite a few frames more to generate so they will probably be static when you're playing the maps outside of forge. (And will probably generate even slower as you add more and more forge pieces) That is, unless they need them dynamic and can amortize the cost across several frames... Probably unlikely...

My guess is that each forge piece has several invisible probes attached to them, inside and around them (depending on the size and shape of the piece) that sample the lighting around them. this is the part that needs to be precomputed every time you move something in forge an switch to player mode. This data is then used to light the forge pieces similar to how Diffusely-Convolved-Environment-Probes are used in Cryengine 3.

If this is done itteratively, you could start to get the appearance of Global illumination and approximated ambient light. You're not likely going to get any cool High frequency indirect shadowing or occlusion from this alone but at least the ambient lighting wont be so flat or dark.

Does this sound about right?
 

Wow, thanks for the link. Conker's allways been a technically interesting game.

Plus, this paper had the simplest explanation of LPVs I've read so far, although I think some of it may be incorrect now. I was diggin around in Cry3 SDK and found options for secondary occlusion.


I'm really want to draw your attention on their soft area shadows. I made a quick cut of the trailers :

http://www.timsoret.com/out/lastofus_lighting.mp4

How did they achieve this look ?

I can't think of an algorithm close to this. Usually in modern games this is just Direct Lighting + SSAO in the shadows, and that's why it feels very flat if you're in the shadows usually. As there is no more electricity in their story, it seems that Naughty Dog really pushed forward the indoor lighting to avoid the flat SSAO look and add some soft shadowing when there isn't sun.

Another look where you can see both direct & indirect shadows :

http://www.timsoret.com/out/lastofus/lastofus_both.gif

Video version of the gif :
http://www.timsoret.com/out/lastofus/lastofus_both.mp4

I noticed this as well and immediately thought, 'Ambient Occlusion Fields and Decals' like the ones used in Infamous 2. It's definitely cool to see this kinda stuff animating.
 
I'm really want to draw your attention on their soft area shadows. I made a quick cut of the trailers :

http://www.timsoret.com/out/lastofus_lighting.mp4

How did they achieve this look ?

I can't think of an algorithm close to this. Usually in modern games this is just Direct Lighting + SSAO in the shadows, and that's why it feels very flat if you're in the shadows usually. As there is no more electricity in their story, it seems that Naughty Dog really pushed forward the indoor lighting to avoid the flat SSAO look and add some soft shadowing when there isn't sun.

Another look where you can see both direct & indirect shadows :

http://www.timsoret.com/out/lastofus/lastofus_both.gif

Video version of the gif :
http://www.timsoret.com/out/lastofus/lastofus_both.mp4

The SSAO of Uncharted 2 was described at GDC2010. You can find the slides here http://www.slideshare.net/naughty_dog/lighting-shading-by-john-hable Start at page 174. What is shown in the slides has clear + shaped artifacts from the bilateral blur. Last of Us probably uses an improvement on the U2 technique.
 
Does implementation of online coop limits the amount of ram/resorces available for other things?
I know that there is this "predictability" thing when you can't make game cinematic/script heavy because you have players doing different things at the same time.
I suppose that there is also same limitation as in multiplayer but on lower scale when you must take into consideration how the other players affect the performance with their actions.
Is there something else and how much does it all impact available resources ?
 
Less than a local co-op with split-screen and large liberty of moving.
So probably you have to reserve some part for the online data not big in Ram volume, but need to be perform in syncro or you have got terrible lag and bad play experience. And for cinematic/script generally when one player active them all players got it despite they're far from the start zone. So not a big hit than solo play, and less if the solo have already AI co-op like in Gears, Halo Reach, etc… But you need more resource than a game with only one character.
 
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Hello,

just wondering:

What could be the reason that current console titles based on Source engine apparently are not running at 60 fps?

Shouldn't the hardware be capable enough to achieve that?
 
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It may be a consistency thing. They can run at 60fps most of the time but Valve chooses to run at 30fps all of the time.

Also, maybe they aren't really fast enough to do 60fps in those titles. Just because a low end gaming PC can do it doesn't automatically mean the consoles can. Low end gaming PC is still far more powerful than a console, especially in CPU power.
 
Not necessarily talking about current low end PCs.

But wouldn't PCs from around 2006, equipped with GPUs equivalent to RSX and Xenos, be capable enough to achieve it, at least at 720p?
 
Not necessarily talking about current low end PCs.

But wouldn't PCs from around 2006, equipped with GPUs equivalent to RSX and Xenos, be capable enough to achieve it, at least at 720p?

I don't think it's that the point. Use the same engine not means is exactly the same from Half life 2... some effect could be updated; Portal 2 on the ps3 use MLAA & motion blur, I can't tell about the rest but the motion blur, for example, it's very expensive in some case when extremely precise, I have in mind Tekken 6 at 576p to keep 60 fps.
 
Tessellated Isabella. :3

Should be interesting to see if they take advantage of environment destruction for dungeon exploration.

Wonder if they'll ship with Enlighten actually enabled. :p
 
Oh, great news! I really love that engine! Wonder how it will work with fantasy based art, or if Dragon Age 3 goes the realistic route...
 
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