texture blending mode for envmaps?

Can anyone tell me what the Mix texture blending mode does?

Actually that whole Map To window is a bit confusing. I’ve been playing with my chrome wheels all day long and the more I play with these settings, the more senseless they become.

While “Add” will add color values from one texture to another and “Sub” will subtract color values from one texture to another, I guess that Mix “fades” two textures into one, perhaps by doing the mean of the color values of the two (or more!) textures.

Refering to the official online documentation should help, though, but I was lazy enough to check it before answering here :wink:

If you want to color your EnvMap texture (or raytraced reflections!), you have to set a color for the base material and press the Cmir button IIRC. Handy for copper and or gold materials if you don’t want mirror-like reflections (untainted by the base color).

Hope this helps,

Say you had a grey (0.5,0.5,0.5) material, and a dark green (0.0,0.5,0.0) texture.
Then the different options with a Col slider value of 1.0:
Add will result in (0.5,1.0,0.5)
Sub will result in (0.5,0.0,0.5)
Mix will result in (0.0,0.5,0.0)
Mul will result in (0.0,0.25,0.0)

Mix is the most common for “painted on” textures - with Col on full it just replaces the colour, with lower Col it mixes in between.
Add is the most common for faked lights (eg a projector) - with Col on full it adds the colours the way lights add up, with lower Col the “light” has less effect.
Mul is also common for faked lights if the object is coloured - shining a yellow (1,1,0) light on a cyan (0,1,1) object should make it look green (0,1,0)
Sub is the most common for faked shadows - some things like particle systems don’t cast shadows so you have to fake it with negative faked-light textures.


The docs are old, and Mix isn’t even listed. What’s in there isn’t really well explained, beyond what’s obvious.

On my system, Cmir doesn’t seem to do anything. But perhaps it only works with Raytracing. It would be nice to know for sure. The docs ought to say this, but they don’t.

I’ve got Col working pretty well now with Mix or Add for my chrome effect. Playing around with it seems to work, but it’s a time-consuming way to learn. :expressionless: