Overview
In the Displays group of attributes the user can specify what images (or Displays) will be rendered; each display can be set to output to a file or a screen window, use a specific Arbitrary Output Variable (AOV), or even contain a subset of the rendered scene. By default, there one display. However, it is possible to add several distinct displays that will all be rendered simultaneously (in a single render pass).
It is possible to add any number of displays, each set to output any AOV that are declared in the shaders.
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