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Generally, there is one shading plugin instance of a RixLightFilter per bound RiLightFilter (RIB) request. This instance may be active in multiple threads simultaneously.

The RIX_LIGHTFILTERPLUGINCREATE macro defines the CreateRixLightFilter() function, which is called by the renderer to create an instance of the light filter plugin. Generally, the implementation of this method should simply return a new allocated copy of your light filter class. Similarly, the RIX_LIGHTFILTERPLUGINDESTROY macro defines the DestroyRixLightFilter() function called by the renderer to delete an instance of the light filter plugin; a typical implementation of this method is to delete the passed in light filter pointer:

    RIX_LIGHTFILTERPLUGINCREATE
    {
        return new MyLightFiler();
    }
    RIX_LIGHTFILTERPLUGINDESTROY
    {
        delete ((MyLightFilter*)bxdf);
    }

RixLightFilter::Filter()

Filter is where the work is done.

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