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Specifies the rendering engine to use for rendering. The available options are the 'REYES' based based algorithm and 'Path Tracer' for the ray tracing based algorithm. A discussion of the Pros and Cons of each is presented in the last section of this page.
Progressive Refinement
This option is only available when using the 'Path Tracer' Render Engine. When this toggle is turned on, the rendering rapidly shows a coarse image and then refines it progressively until completed. This option is effective only for images outputted directly to a window on screen (i.e. to the Maya Render View or to 3Delight i-Display). During batch rendering (i.e. when using Maya Batch) this option is ignored.
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