Fog color depht variation

I find myself wanting more controll over fog and back side color depht variation on the standard material.
A cool map maybe to use in this situation would be a thickness/depht map you could plug into either slot?

Some way to controll hue/saturation shift depending on the thickness of the object would be very nice.

-Tom

After doing some research, It might be that What we need is a way to control the rgb depht contribution in the translucency section.
After what I can see at least the cycles renderer for blender have an extra rgb slot in the depth section for translucency

The fog color in VRayMtl is already a way to control the depth for the red/green/blue channels separately.

Best regards,
Vlado

You are right off course, I am just having a hard time wrapping my head around it I guess.
I am starting to understand though.. After 15 years of vray…In my defence, all this bruteforce glossy refraction stuff have been to slow to render for a while.

-Tom