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The ordinal position of a parameter in the parameter table is the integer paramId used to evaluate parameter inputs using the RixShadingContext::EvalParam method. Because these need to be kept in sync, it is recommended that you create a parameter enumeration to keep (a private enum type) to keep track of the order that your parameters were created in the table. The enumeration can be used later on when calling RixShadingContext::EvalParam  in the body of the shader. Following the three parameter table entries above:

enum paramId
{
    k_resultC=0, // output
    k_density,
    k_placementMatrix,
    k_numParams
};

Anchor
synchronization synchronization

Synchronization

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