Method and apparatus for multi-phase rendering

Abstract

In a method for rendering an evolving three-dimensional scene description as a series of two-dimensional images (frames), the evolving scene description includes object geometries G and their associated shader procedures S. Each shader procedure S is factored into a static procedure S and a dynamic procedure S such that S(A,I)=S (S (A,R),I), where A denotes the appearance parameters required to shade objects, I denotes an instance of the control parameters, and R denotes a range of control parameters which include I. Similarly, the rendering procedure TSI (transform, sample, and interpolate) for object geometry is factored into a static procedure TSI and a dynamic procedure TSI such that TSI(G,I)=TSI (TSI (G,R),I). The factorization of both S and TSI is chosen to significantly reduce the overall rendering time for the evolving scene. Specifically, viewpoint independent or weakly viewpoint dependent computations S (A,R) and TSI (G,R) are computed in the static phase of rendering and stored either as independent data structures or as a single combined data structure called the internal representation. This internal representation is then processed by the dynamic phase of rendering to produce each frame. Since the required dynamic computations to produce a frame are significantly reduced and the required static computations run infrequently both as a result of a clever factorization and an efficient internal representation, the overall rendering time is reduced.