We present an output-sensitive rendering algorithm for
accelerating walkthroughs of large, densely occluded
virtual environments using a multi-stage Image Based
Rendering Pipeline. In the first stage, objects within a
certain distance are rendered using the traditional
graphics pipeline, whereas the remaining scene is
rendered by a pixel-based approach using an Image
Cache, horizon estimation to avoid calculating sky
pixels, and finally, ray casting. The time complexity of
this approach does not depend on the total number of
primitives in the scene. We have measured speedups of
up to one order of magnitude.
Austrian Science Foundation under contract no. P-11392-MAT and
Ars Creat Game Development.
Contact: Michael Wimmer
||Ray casting is used to cover the pixels of the Far Field (beyond 100m).
Pixels above the horizon are culled early
||A view over much of the virtual city that was used for the walkthroughs
||A typical view from a walkthrough sequence in the city