@inproceedings{LierMartinekStammingeretal., author = {Lier, Alexander and Martinek, Magdalena and Stamminger, Marc and Selgrad, Kai}, title = {A High-Resolution Compression Scheme for Ray Tracing Subdivision Surfaces with Displacement}, series = {Proceedings of the ACM on Computer Graphics and Interactive Techniques}, volume = {1}, booktitle = {Proceedings of the ACM on Computer Graphics and Interactive Techniques}, number = {2}, publisher = {The Association for Computers in Mathematics and Science Teaching}, doi = {10.1145/3233308}, pages = {1 -- 17}, abstract = {Subdivision surfaces, especially with displacement, are one of the key modeling primitives used in high-quality rendering environments, such as, e.g., movie production. While their use easily maps to rasterization-based frameworks, they pose a significant challenge for ray tracing environments. This is due to the fact that incoherent access patterns require storing or caching fully tessellated and displaced meshes for efficient intersection computations. In this paper we use a two-tier hierarchy built on a scene's patches. It relies on compressed and quantized bounding volumes on the second tier to reduce the size of the BVH itself. Based on this acceleration structure, we propose a quantized, compact approximation for leaf nodes while being faithful to the underlying patch-geometry. We build on recent advances and present a system that shows competitive performance regarding run-time speed, which is close to full-resolution pre-tessellation methods as well as to previous compression approaches. Ultimately, we provide strong compression of up to a factor of 5: 1 compared to state-of-the-art methods while maintaining high geometrical fidelity surpassing similarly compact approximations and getting close to uncompressed geometry.}, language = {en} } @article{SelgradLierMartineketal., author = {Selgrad, Kai and Lier, Alexander and Martinek, Magdalena and Buchenau, Christoph and Guthe, Michael and Kranz, Franziska and Sch{\"a}fer, Henry and Stamminger, Marc}, title = {A Compressed Representation for Ray Tracing Parametric Surfaces}, series = {ACM Transactions on Graphics}, volume = {36}, journal = {ACM Transactions on Graphics}, number = {1}, publisher = {ACM}, address = {New York, NY, USA}, doi = {10.1145/2953877}, pages = {1 -- 13}, abstract = {Parametric surfaces are an essential modeling tool in computer aided design and movie production. Even though their use is well established in industry, generating ray-traced images adds significant cost in time and memory consumption. Ray tracing such surfaces is usually accomplished by subdividing the surfaces on-the-fly, or by conversion to a polygonal representation. However, on-the-fly subdivision is computationally very expensive, whereas polygonal meshes require large amounts of memory. This is a particular problem for parametric surfaces with displacement, where very fine tessellation is required to faithfully represent the shape. Hence, memory restrictions are the major challenge in production rendering. In this paper, we present a novel solution to this problem. We propose a compression scheme for a-priori Bounding Volume Hierarchies (BVHs) on parametric patches, that reduces the data required for the hierarchy by a factor of up to 48. We further propose an approximate evaluation method that does not require leaf geometry, yielding an overall reduction of memory consumption by a factor of 60 over regular BVHs on indexed face sets and by a factor of 16 over established state-of-the-art compression schemes. Alternatively, our compression can simply be applied to a standard BVH while keeping the leaf geometry, resulting in a compression rate of up to 2:1 over current methods. Although decompression generates additional costs during traversal, we can manage very complex scenes even on the memory restrictive GPU at competitive render times.}, language = {en} }