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    RIX_PATTERNCREATE
    {
        return new MyPattern();
    }
    RIX_PATTERNDESTROY
    {
        delete ((MyPattern*)pattern);
    }

Anchor
ComputeOutputParams ComputeOutputParams

Computing Pattern Output

ComputeOutputParams()   is the heart of a pattern plugin: it evaluates the input parameters, and computes the pattern output. It is called once per graph execution, and all outputs must be computed during this single invocation. The number and type of outputs should match the number and type of outputs declared in the parameter table. The domain of evaluation of this function is a shading context, which is of type RixShadingContext, defined in RixShading.h. 

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