Surfel stripping

This paper presents an efficient combination of techniques for fast stripping and multiresolution rendering of Point-Based Surfaces (PBS) called Surfel Stripping. Surfel Strips are small triangle strips that interpolate the PBS. There are two major contributions. First, at loading time, we efficiently convert the PBS into triangle strips. This is done by first generating a set of overlapping small triangular meshes that interpolate the PBS, then removing redundant triangles and finally stripping the small triangular meshes by using a cache-friendly stripping method. All these operations are performed by using an octree data structure. Second, we reuse this data structure for providing a multiresolution interactive visualization of the surfel strips at rendering time. Since Surfel Stripping is local and very fast, it can be used in a lot of situations as an object-space alternative to the image-space surface splatting and thus be considered half way between point-based rendering and local polygonal generation. Rendering Surfel Strips is very efficient since it neither requires multi-pass rendering nor time-consuming vertex/fragment shaders compared to surface splatting. We show also how to exploit the locality of the surfel strips for maintaining compatibility with point-based modeling tools, such as local deformations of surfaces. We finally give some examples of well known visual enrichments developed for polygons, directly applied to PBS thanks to surfel strips.