Hierarchical Image Caching for Accelerated
Walkthroughs of Complex Environments
We present a new method that utilizes path coherence to accelerate walkthroughs
of geometrically complex static scenes. As a preprocessing step, our method
constructs a BSP-tree that hierarchically partitions the geometric primitives
in the scene. In the course of a walkthrough, images of nodes at various
levels of the hierarchy are cached for reuse in subsequent frames. A cached
image is reused by texture-mapping it onto a single quadrilateral that is
drawn instead of the geometry contained in the corresponding node. Visual
artifacts are kept under control by using an error metric that quantifies
the discrepancy between the appearance of the geometry contained in a node
and the cached image. The new method is shown to achieve speedups of an
order of magnitude for walkthroughs of a complex outdoor scene, with little
or no loss in rendering quality.
| A top-down view of the island.
|| An artifact-free view created using hierarchical
|| A view created by drawing geometry.
|| A view of the BSP nodes.