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The RIX_BXDFPLUGINCREATE() macro defines the CreateRixBxdfFactory() method, which is called by the renderer to create an instance of the bxdf plugin. Generally, the implementation of this method should simply return a new allocated copy of your bxdf factory class. Similarly, the RIX_BXDFPLUGINDESTROY() macro defines the DestroyRixBxdfFactory()  method  function called by the renderer to delete an instance of the bxdf plugin; a typical implementation of this method function is to delete the passed in bxdf pointer:

    RIX_BXDFPLUGINCREATE
    {
        return new MyBxdfFactory();
    }
    RIX_BXDFPLUGINDESTROY
    {
        delete ((MyBxdfFactory*)bxdf);
    }

RixBxdfFactory::BeginScatter()

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