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- Have multiple rendering quality levels. It is usual to have a render pass with settings for a draft render and another one for high quality renders.
- Split rendering of different objects in the scene (such as foreground and background objects) in different passes. In this case, a render pass is equivalent to the rendering of a layer which might be composited in a compositing software later in the pipeline.
- Have a one or more passes setup to generate some texture maps (or shadow maps) and the following pass use these maps in the final image.
