*renamed* Lighting and shadows in games

[macabre]

I don't remember hearing any of those in the podcast (just shadows), and it's doubtful they will have them either.
Maybe some other "fake" HDR, but not selfshadowing

It`s in there @ 18:25

 

[ultragpu]

I don't remember hearing any of those in the podcast (just shadows), and it's doubtful they will have them either.
Maybe some other "fake" HDR, but not selfshadowing

18:25-18:36 "new lighting and shadowing, like self-shadowing, what else does it do? light scattering and all sorts of things that makes it look better"
ok i dont know if it's HDR but self-shadowing is definetly there.

 

[Cheezdoodles]

I don't remember hearing any of those in the podcast (just shadows), and it's doubtful they will have them either.
Maybe some other "fake" HDR, but not selfshadowing

Huh? Why shouldn't the game have selfshadowing? GTA4 has selfshadowing on every person in the game. So has most good graphical games... Resistance will have selfshadowing, as any other game with self respect these days...

 

[betan]

Huh? Why shouldn't the game have selfshadowing?

I don't think I said anything like that.
But looking at your example, one can argue self shadowing is overrated since people mistake it with some other cheaper tricks.

GTA4 has selfshadowing on every person in the game.

I don't think so.

So has most good graphical games... Resistance will have selfshadowing, as any other game with self respect these days...

Self shadowing means that a model receives the shadow it casts, like shadow of arm, ear, hair, etcetera.
As far as I can see most games (mostly) use normal and texture based shadowing to imitate it.

It`s in there @ 18:25

18:25-18:36 "new lighting and shadowing, like self-shadowing, what else does it do? light scattering and all sorts of things that makes it look better"
ok i dont know if it's HDR but self-shadowing is definetly there.

To be honest, I was talking about the previous podcast, didn't notice 2 weeks already had passed.
Yes it says scattered light and self shadowing.

 

[nAo]

Self-Shadows are not some super secret technique, in many cases it's actually easier to have self-shadowing geometry than to not have it.

 

[betan]

Self-Shadows are not some super secret technique, in many cases it's actually easier to have self-shadowing geometry than to not have it.

Is it cheaper though (maybe besides some piece of vram)?

In anycase, the games that do have selfshadowing tend to have frickery and jagged shadows as well.

Hopefully next Star Wars game will have properly filtered self shadows. (just fishing)

 

[Cheezdoodles]

I don't think I said anything like that.
But looking at your example, one can argue self shadowing is overrated since people mistake it with some other cheaper tricks.

Looking at your posts, it seems you dont know what self shadowing is.

Self-Shadowing is a computer graphics lighting effect, used in 3D rendering applications such as computer animation and video games. Self-shadowing allows non-static objects in the environment, such as characters and interactive objects (buckets, chairs, etc), to cast shadows on themselves and each other.

There is no "right" way to do selfshadowing, you can do it however you want. If its cheap trickery or by GI doesn't matter, its still self-shadowing as long as characters cast shadows on themselves and on each other. And most games these days have this, in some way or another..

 

[deepbrown]

Looking at your posts, it seems you dont know what self shadowing is.

Self-Shadowing is a computer graphics lighting effect, used in 3D rendering applications such as computer animation and video games. Self-shadowing allows non-static objects in the environment, such as characters and interactive objects (buckets, chairs, etc), to cast shadows on themselves and each other.

There is no "right" way to do selfshadowing, you can do it however you want. If its cheap trickery or by GI doesn't matter, its still self-shadowing as long as characters cast shadows on themselves and on each other. And most games these days have this, in some way or another..

Isn't it meant to be dynamic...and real-time? Rather than "canned"?

 

[Cheezdoodles]

Isn't it meant to be dynamic...and real-time? Rather than "canned"?

Um, isn't it rather obvious that for non-static objects to cast shadows in a game, on eachother and on the environment it needs to be renedered in realtime? You need to recalculate shadows every time the non-static object moves....

 

[_phil_]

static objects can have self shadowing too...

 

[Cheezdoodles]

Does UE III support AA at all?

Yes it does. But if i remember correctly UE III did not support tiling (or because of their shadow system, it led to huge penalties in combination of MSAA).

Mod Note: Copied from Frame Rate Analysis Thread

 

[Cheezdoodles]

static objects can have self shadowing too...

Yeah, but the shadows wouldn't move unless the sun\ light moes..

But either way, my comment was an reply to deepbrowns question about realtime and what not, which is rather obvious that you need to render the shadows in realtime to get self-shadowing with non-static objects.

 

[AlNom]

Yes it does. But if i remember correctly UE III did not support tiling (or because of their shadow system, it led to huge penalties in combination of MSAA).

Hope these help:

http://forum.beyond3d.com/showpost.php?p=744476&postcount=64

The only reasonable excuses I've heard for lack of AA other than not enough time is the one Epic uses to justify it in the Unreal3 engine games. Basically their shadowing algorythm projects screen space pixels back into light space so they would have to do 2x or 4x the work for shadowing if AA was enabled, but that's true reguardless of the AA implementation.

http://forum.beyond3d.com/showpost.php?p=757471&postcount=43

There are many ways to do it...
But the traditional method is to resubmit the recieving polygons, and use the shadow map to determine if they are in shadow.

What unreal does is reverse transform the pixels in the frame buffer which has the advantage that it's cost is unrelated to the complexity of the recieving geometry, with the obvious disadvantage that if you have more samples effected cost goes up linearly with that. You also don't have to worry about which bits of geometry receive shadows in this model.

Whether it's a performance win depends on the likely complexity of the shadow recievers, and how effectively you can cull pixels and triangles in the first case.

It's an interesting approach, what I've seen of GOW, I'm a bit surprised Epic thinks it's a win performance wise, but without trying both methods it's a difficult call.

http://forum.beyond3d.com/showpost.php?p=821432&postcount=6

It's been covered before, do a search, basically they reverse project screen space pixels into shadow space. So the cost of the shadows is proportional to the number of pixels prior to the downsample. So 2xMSAA doubles the cost of shadow rendering.

It strikes me there are several ways they could try and address this, but I have to assume that they tried them.

But UE3 doesn;t specifically limit you to any particular shadow approach, the app could easilly provide a different solution.

On a side note, Army of Two must be one of the few UE3 games to have proper/consistent 2xMSAA; performance didn't seem so bad, but I haven't played the entire game. Just the demo.

 

[deepbrown]

Um, isn't it rather obvious that for non-static objects to cast shadows in a game, on eachother and on the environment it needs to be renedered in realtime? You need to recalculate shadows every time the non-static object moves....

Well then - it's not as common as you think. And it's certainly not always done well if it is done.

 

[Mintmaster]

Selfshadowing to one degree or another is present in all games i own on the X360 and PS3. It may vary from all characters casting shadows to just a few, but i cannot remember a game without any selfshadowing this generation.

Ratchet and Clank doesn't have it, nor do Source engine games. Those aren't piss-poor games.

There are lightmaps from enviroment, and then there are shadows from characters onto the environment. No self-shadowing, no shadowing from one dynamic object to another.

 

[Cheezdoodles]

I dont own those games, but either way, its not like selfshadowing is some misterious technique, plenty of games use it.

 

[DJ12]

I thought Ratchet did have it just not on everything.

It's been a while since I've played it.

 

[nAo]

Listen to me, even Xbox 1 shooters had self-shadowing. No, not static shadows coming off characters, SELF SHADOWING. Self shadowing is NO secret.

1) those are stencil shadows (which is a technique no one almost uses anymore), not shadow maps
2) they should have worried more about indirect lighting IMHO..those black shadows are fugly.

 

[Mintmaster]

Hope these help:

One thing you should note is that Heavenly Sword does shadows in the same way as UE3, but has AA enabled. There's a small discussion between me and him somewhere where he tells me about the artifacts in his approach, but there's a few questions of mine that he couldn't answer due to NDA.

KZ2's approach is a good way of keeping the cost increase well below the 2x/4x that ERP is alluding to. You split the shadow map samples between the pixel's subsamples.

What I'm really waiting for from 360 devs is the use of dynamic branching to jack up the sample count at shadow edges. The most robust way to do this is to use variance shadow mapping to identify the areas that may not be entirely shadowed or unshadowed.

 

[Neb]

1) those are stencil shadows (which is a technique no one almost uses anymore), not shadow maps
2) they should have worried more about indirect lighting IMHO..those black shadows are fugly.

But its still dynamic self-shadowing right or?