COD4 lighting

[Belgarion]

Does anyone know how the COD4 engine renders? I checked the COD4 wiki page, but the info on the engine is fairly skimpy. Is it all real-time lighting or are there lightmaps involved? Just curious.

[e-freak]

AFAIK lightmaps and the system is fairly close to the source lighting (have to ask a friend of mine who did some research on the subject lately)

[Sentura]

yeah i'd reckon so as well since it is a heavily modified q3 engine

[Pongles]

actually, it's not strictly Q3. for COD4 they have written their own. however, it's likely that they followed in the same path as Q3.

[Frittz]

Definately Lightmaps. There is some realtime lighting but mainly in single player levels.

[Erratic]

The majority of the shadows in the environments looked like shadowmaps to me, considering they have a level of detail on them, making them dynamic. I don't recall seeing a lot of baked in lighting anywhere at all. But that's just my observation, there's a few guys from IW around here who could confirm this, no?

[Belgarion]

Yeah. People from IW, give me an answer!

[mjens]

I was looking at some shadows on multiplayer levels and I think these are shadowmaps (nice res., works with HDR). Also it's still old and good COD4Rad.exe (older Q3Rad).

[Belgarion]

I've been looking around, but I haven't found an *easy* to read explanation of how shadowmapping works. Anyone care to explain or link me?

[mjens]

http://en.wikipedia.org/wiki/Shadow_map

Easy explanation:

A guy from IW wrote some haxor code which makes some crazy counts. It checks where is the main light (sun) on the level and generates info about shadows form that light. Engine is rendering it with cool filters The rest of the lights are dynamic (the shadow is raytraced dynamicly) or some static included to radiocity count on level compilation stage. Not sure about it but it's seems easy

[Warby]

http://en.wikipedia.org/wiki/Shadow_map

Easy explanation:

A guy from IW wrote some haxor code which makes some crazy counts. It checks where is the main light (sun) on the level and generates info about shadows form that light. Engine is rendering it with cool filters The rest of the lights are dynamic (the shadow is raytraced dynamicly) or some static included to radiocity count on level compilation stage. Not sure about it but it's seems easy

that is only how it is APPLIED to the world the shadow map itself is all precalculated you can tell by the lack of flickering on the edges !

there is no dynamic ray tracing going on here or in any engine for the next at least 5 or probably 10 years ( yeah yeah ... i have seen that raytrace quake 3 and quake 4 video still wont happen any time soon )

all i am wondering is how they handle THE INSANE resolution of those shadows memory wise ... i guess they can store some bytes by making it all 1 bit color depth but would that really cut it ?!

[mjens]

Yep, raytraced shadows aren't used - too much 3DSMax and I call all dynamic shadows as raytraced :x

I asked few guys how it can be done and the only thing that is most possible is to save these to hi-res shadowmap from polys which are on shadow edges and store info about fully shadowed polys... I'll tell you more when I'll show that shadows to few more guys who can know what it is...