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RiBegin("launch:prman? -ctrl $ctrlin $ctrlout -dspy $dspyin $dspyout -xcpt $xcptin")
The Ri Control API The Ri Control API provides functions a client application will find useful when interacting with a detached prman process. These functions will not work if the launch string does not contain "-ctrl $ctrlin $ctrlout".
For off-line rendering, display drivers are loaded as dynamic libraries into the renderer's process. When writing an interactive application, it is often desireable to load a user-written display driver into the client application process and configure prman to ship pixels to the driver through a fast, low-latency interprocess communication channel. The "-dspy$dspyin $dspyout" option directs the rendering context to configure the detached prman to send pixels back to the client application. To load a display driver directly, an application should use DspyRegisterDriverTable described in Directin Direct-linked Display Driver Registration
Finally, an application may want error messages processed by the error handler installed in the application's process. The "-xcpt $xcptin" option directs the rendering context to send error messages from the detached process to the client process for delivery.
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The table below shows which commands may be specified inside a RiMotionBegin-RiMotionEnd block. If the Motion Blur capability is not supported by a particular implementation, only the transformations, geometry, and shading parameters from t0 are used to render each moving object.
Moving Commands
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