Specularity in Doom 3

[STiFU]

I was wondering whether Doom 3 supports colored specular, since the newest version of crazybump does and it looks really neat on some textures. But I guess it doesn't since everyone has ever talked about greyscales.

 

Is there any game at all which supports colored specular?

[OrbWeaver]

Yes.

[demagogue]

I hope you mean "Yes, Doom 3 supports colored specular" ... as opposed to "Yes, there is at least one game out of all that supports it".

[OrbWeaver]

Yes, Doom 3 supports coloured specular. It tends to be fairly rarely used, however, probably because many people don't realise it exists.

[jdude]

Someone want to post a piccy so we can see what it looks like?

[Baddcog]

This teapot has the slightest bit of aqua/blue speculartiy and yellow spec on the gold part. You can see it right on the edge of the shadows.

The problem with spec in Doom3 is it is VERY bright and you almost have to use black to make it subtle. Same with colors, if I used the color of blue I wanted to see the teapot would be neon blue.

 

[OrbWeaver]

I think it's the light that's too bright in that shot, not the specular.

 

One problem with specular though is that the hardness ("glossiness") is fixed at quite a low level, suitable for giving things a slight sheen or "wet look", but not suitable for very shiny metal objects. In theory it is possible to vary the hardness using a glossmap, but when I tried this it could only be done using the diffuse map's alpha channel (which would interfere with alphatesting) rather than the specular map's.

[Baddcog]

You're right that the light in thta shot is bright, but that's not the prob with specular being overbright as you also mentioned.

 

I did alot of testing to get it where I wanted. If the color was too bright it really was like neon - in shadows.

[STiFU]

That's cool. I made an Ivytexture and it looks a lot better with colored specular, so yay, I can use it now!!

[Crispy]

In theory it is possible to vary the hardness using a glossmap, but when I tried this it could only be done using the diffuse map's alpha channel (which would interfere with alphatesting) rather than the specular map's.

Ah, interesting. If you kept the alpha channel under the alphatest value though, presumably that would work? Worth investigating for objects that don't use alphatest, anyway, like the teapot.

[OrbWeaver]

Ah, interesting. If you kept the alpha channel under the alphatest value though, presumably that would work? Worth investigating for objects that don't use alphatest, anyway, like the teapot.

 

Yes, I suppose that is possible -- set the alphatest value at 0.1, and use 0.1 - 1.0 to represent glossiness. It's a horrible hack, but possibly the only way if Doom 3 truly cannot read the alpha channel of a specular map (rather than me just not getting it right).