US Patent 7315302 Composite rendering 3-D graphical objects

Methods and apparatus for 3-D image compositing. The compositing system can be used to render 3-D objects together to a scene, to combine together separately rendered 3-D objects in a scene including previously rendered objects, or to render some objects together while separately rendering and combining together other objects in a scene. The system correctly handles image processing effects including anti-alias, motion-blur and depth-of-field effects in all regions of the scene, including regions where the objects within the scene intersect. The resulting scenes have the same high image quality regardless of which image objects are rendered together and which are later combined or composited to the final image.