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This documentation is intended to instruct developers in the authoring of custom projections. Developers should also consult the RixProjection.h header file for complete details. The source code for the PxrOrthographic and PxrPerspective projection plugins may be found in the plugins/projection/simple subdirectory of the PixarRenderMan-Examples package.

A projection plugin is used to model camera and lens behavior. These plugins are responsible for taking stratified random samples as input from the renderer and turning these into primary camera rays.

RixProjectionFactory

RixProjectionFactory is  is a subclass of RixShadingPlugin, and therefore shares the same initialization, synchronization, and parameter table logic as other shading plugins. Projections do not support lightweight instances, and therefore CreateInstanceData() should not be overridden as any created instance data will not be returned to the factory.

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