Matte VEX node

Implements a matte shader that occludes geometry behind the surface being rendered.

See also: Lighting Model, Parameter, Shadow Matte, Two Tone

This operator implements a matte shader that occludes geometry behind the surface being rendered. The output image, however, will have the alpha value specified.

The output color is always zero and no lighting is applied.

The operator is well suited to compositing tricks. When the matte shader is hit by shadow rays, the shadow amount determines how much of a shadow will be cast by the surface, meaning that both the opacity and alpha outputs will inherit the shadow amount. When the shader is not hit by shadow rays, only the alpha output will inherit the shadow, while the opacity is set to 1.

You will typically connect the color, opacity, and alpha outputs straight into the Cf, Of, and respectively Alpha inputs of the “Output Variables” operator.

It is also possible to disable fog on the surface. To do so, either use the VEX Matte SHOP in the Shaders module, or create a Parameter VOP, set its type to “Toggle (int)”, name its parameter “__nofog“ (with two underscores) and enable its ”Export Parameter“ option. You do not need to connect its output to any operator.