Stencil is one of the most useful tip when you want to control finely the way the shader changes from one texture to another, on the same object, and with the use of a single material index.

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And thanks to the Nodes editor, it is also possible to use stencils with materials, for ever more complex materials and textures setups, that may rely on stencil themselves!.


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For Blender: 2.50Alpha 2 and better