Soul © Disney/Pixar

Integrators take the camera rays and return results to the renderer. For the main integrators these are estimates of the light energy (radiance) from the surfaces seen from the outside along the rays. These main integrators are responsible for computing the overall light transport, that is, light that travels from a light source through your scene from object to object (or through objects and volumes) to reach the camera. Interior integrators assist in specialized cases by handling the light within surfaces or volumes. We provide three main production quality integrators, though users can substitute their own.

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