GradientMapping

Gradients can be used to enhance and control texture maps.

Vertical Gradient Baking

The Dota2 Character Art Guide describes how to bake a vertical gradient into the diffuse, to emphasize depth and create focus.

Baking a gradient map in 3ds Max, using a script. See MaxScript: Gradient Map Polycount Forum thread. Image by Juan 'monster' Martinez.

Baking a gradient map in Maya. Image by Adam 'afisher' Fisher.

Gradient Remapping

Gradient remapping is a method to replace the colors of a texture using 1D gradients, for more variation.

Using a gradient to remap the colors of a texture. See Tutorial - Gradient Mapping & UDK Polycount Forum thread. Image by Rasmus 'rasmus' Deguchi.

Using a gradient to remap the colors of a texture. See Gradient Mapping - An Awesome Way to Get Cheap Variation in Textures. Image by Ryan James Smith.

Gradient mapping in Unity using custom shaders. See Sketchbook:Eric Chadwick. Image by Eric Chadwick.

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