Colored Spec Maps.

Incomitatum

I taught myself how to texture. I know, I know, it shows. That was some time ago, back in the heyday of Bryce, and Poser (did they move on, or did I?)...

Recently my colleagues and I are stumped. We see lots of professionals using Colored Spec maps...

I have not been able to find a resource about the theory behind this. Why is skin blue... etc?

I know what specmaps are good for. I find it odd, that we don't use Gloss Maps as well. The brightness of a pixel will determine the specularity across a surface.

What about color? Does the brightnes of a pixel still matter (I would assume)?

Does the color affect the specular Color?

Do most artists still make a traditional, grey-scale, map, and then add color over it?

Do more and more games support this in their shaders?

In Max, you would have to drop this in the specular color, -as well- to achieve this effect, correct?

Your experience on this matter would be appreciated. Links to tutorials and theory are always welcomed too.

Thank you all for your patience,

-Andrew B. Chason

Hito

specular intensity map affects how much the pixel picks up the color of the light you have in the scene.

gloss map affects how big of an area picks up the color of the light you have in the scene, provided you have specular settings initially, by a map or an overall setting.

specular color mixes with color the light, and the size and intensity is affected by specular intensity map and the gloss map combined; as well as the colors themselves. Analogus colors adds up; complimentry colors cancell out. the inset has the same map in diffuse channel at 50%; though the result is the same with or without the diffuse channel.

The teal cancelled out the red specular;
the orange cancelled out the blue;
the blue mixed with the yellow for green;
the red mixed with the yellow for orange;
the orange mixed with the green for the light yellow green

Computers use additive colors so things don't work quite the same as mixing pigments.

Incomitatum

So, your -one- spec map, made for the industry needs to be on -both- Color, and Level. Right?

Paint in the level first, and the add a color overlay?

Why blue for skin? Are there other standards that follow from that question. Red for Cats, Yellow for toothbrushes (I am being a little silly, but I don't know all the rules)?

-Andrew

MoP

If you read upwards in this forum, there's a sticky thread with a LOT of posts and useful information on this subject, definitely read it, it will answer all your questions!

http://boards.polycount.net/showflat.php?Cat=0&Board=3&Number=81058&page=0&fpart=1

CheeseOnToast

Try this little experiment Incomitatum. In photoshop, take the layer that has your flesh tones in it, and duplicate it. Now hit ctrl+I to invert it. Notice it turns a bluish colour? Using the opposite colour of your diffuse map will produce grey/white specular highlights, without adding more colour saturation. Set this layer mode to "colour dodge", and you will find that the flesh area turns pure white.

Another experiment : paint a red dot, then duplicate the layer as before. Set the layer mode to colour dodge again. See how saturated it becomes? Play around with the hue and brightness sliders to see what happens. The closer the dodged layer gets to being turquoise, the less saturated the dot will become. This is just an approximation of how spec works in-game, but it's a pretty good starting point, I've found.