1. A system, comprising: a processor configured to: generate a first frame from a three-dimensional model of a scene in a first state; generate a second frame from the three-dimensional model of the scene in a second state; and encode the second frame at least partially as a difference determined from known geometries of the three-dimensional model of the scene and a virtual camera in the first state and the second state; and a memory coupled to the processor and configured to provide the processor with instructions.