What is the deal with shadows?

[kelco]

What is the deal with rendering shadows in game? I think its high time something was done about the absolute slaughter to my fps that this particular setting causes. I was kidding about buying a shadow accelerator, but a 20fps hit is kind of insane to me. Guild Wars 2 on ultra runs fantastically when theyre off, even on low it taxes my 570 pretty hard. Diablo3 is the same way, as is WoW.


/rant

 

[-Slacker-]

What are you running them on?

 

[Arkaign]

Yeah shadows is one of the first things I scale back if a game isn't running fast enough for my tastes. It's a setting that usually is not much difference to look at unless you're at a dead stop and just staring intently at minor details.

 

[Absolution75]

For every shadow in the game, you need to re-render the scene to a depth buffer texture to calculate what pixels the light hits.

If you have 5 lights, the scene will get rendered 5 times, then there's a ton of blurring and texture sampling that is done to get nice results. Shadows are just slow.

It'd be nice if there was an easier/more efficient way....

 

[lopri]

Also add indirect lights for photorealism.

 

[hawtdawg]

I think someone just needs to figure out a better way to do them

 

[Elixer]

There are different ways to do them, but most engines aren't written in a way that would be easy to change.
Shadows are very complex to do correctly, and if you want perfect, you get into ray tracing which is very CPU intensive, and really, really slow.

The only sane way to do them right now in action games, is do multiple passes, so you need a fast GPU to do that quickly.

 

[Yuriman]

What is the deal with rendering shadows in game? I think its high time something was done about the absolute slaughter to my fps that this particular setting causes. I was kidding about buying a shadow accelerator, but a 20fps hit is kind of insane to me. Guild Wars 2 on ultra runs fantastically when theyre off, even on low it taxes my 570 pretty hard. Diablo3 is the same way, as is WoW.


/rant

Turn off supersampling. I can run the game maxed on a pair of HD4870's with supersampling off.

 

[futurefields]

even on low it taxes my 570 pretty hard. Diablo3 is the same way, as is WoW.


/rant

that's weird, I pull about 80-100 fps average with everything maxed diablo 3 with a 1gb 6850 @ 1080p

 

[BD231]

that's weird, I pull about 80-100 fps average with everything maxed diablo 3 with a 1gb 6850 @ 1080p

When there's not 50 demons on the screen spamming their range attacks as well as three other players doing the same of course ...

 

[futurefields]

When there's not 50 demons on the screen spamming their range attacks as well as three other players doing the same of course ...

It doesn't seem to make much difference really on my end, I am able to maintain 60fps vsync always.

 

[kelco]

It doesn't seem to make much difference really on my end, I am able to maintain 60fps vsync always.

I'd need to see a fraps of that... Not saying I don't beleive you, but I havent seen Diablo3 run perfect on anyone's machine.

 

[Gryz]

I think someone just needs to figure out a better way to do them

I think it has more priority to improve the speed of light first.
66 milliseconds Round Trip Time (ping) across the Atlantic Ocean is just too much.
Light was that slow decades ago. I just can't believe nobody came up yet with a way to improve the speed.

 

[futurefields]

I'd need to see a fraps of that... Not saying I don't beleive you, but I havent seen Diablo3 run perfect on anyone's machine.

turn vsync on if you havent already

vsync off is a horrorshow

 

[toyota]

depends on the game but to me its usually the cpu not the gpu where any trouble handling shadows pops up. for example the shadows in GTA4 are one of the biggest framerate killers and its nearly all cpu related. the dynamic shadows in the first Borderlands would cause issues in some spots and that too was pretty much all cpu related.