Bounded-Error Interactive Ray Tracing
نویسندگان
چکیده
Ray tracing, which computes radiance, is traditionally regarded as an off-line rendering algorithm that is too slow for interactive use. In this paper, we present an interactive system that uses 4D interpolants to approximate radiance, while providing guaranteed error bounds. Our system exploits the object-space, ray-space, image-space and temporal coherence in radiance to accelerate ray tracing. Our system explicitly decouples the two operations of the ray tracer — shading computation and visibility determination at each pixel, which we call pixel assignment. Rendering is accelerated by approximating the shading computation while guaranteeing correct pixel assignment. Without any pre-processing, the system lazily collects 4D radiance samples, which are quadrilinearly interpolated to approximate radiance. An error predicate conservatively guarantees that the relative error introduced by interpolation is bound by a user-specified . The user can change this parameter to trade off performance for quality. The predicate guarantees the error bound by detecting discontinuities and non-linearities in radiance. If error cannot be guaranteed for an interpolant, the system adaptively refines the interpolant. Pixel assignment is accelerated using a novel algorithm that reprojects 4D interpolants to new viewpoints as the user’s viewpoint changes. Using reprojection, a fast scan-line algorithm achieves high performance without sacrificing image quality. This lazy interpolant system with reprojection speeds up ray tracers substantially for smoothly varying viewpoints. In this paper, we present the design, implementation and results for our system. We expect our techniques to be useful for interactively rendering general scenes as well as for batch off-line rendering processes.
منابع مشابه
Accelerated Bounded-Error Ray Tracing Using Per-Surface Radiance Interpolants
Ray tracing, which computes radiance, is usually regarded as an off-line rendering algorithm that is too slow for interactive use. In this paper, we present a system that uses per-surface four-dimensional interpolants to approximate radiance, while providing guaranteed error bounds. Our system exploits object-space, ray-space, image-space and temporal coherence to accelerate ray tracing. Our sy...
متن کاملAdaptive Quantization Visibility Caching
Ray tracing has become a viable alternative to rasterization for interactive applications and also forms the basis of most global illumination methods. However, even today’s fastest ray-tracers offer only a tight budget of rays per pixel per frame. Rendering performance can be improved by increasing this budget, or by developing methods that use it more efficiently. In this paper we propose a g...
متن کاملRadiance Interpolants for Interactive Scene Editing and Ray Tracing by
Ray tracers are usually regarded as off-line rendering algorithms that are too slow for interactive use. This thesis introduces techniques to accelerate ray tracing and to support interactive editing of ray-traced scenes. These techniques should be useful in many applications, such as architectural walk-throughs, modeling, and games, and will enhance both interactive and batch rendering. This t...
متن کاملShell: Accelerating Ray Tracing on GPU
Ray tracing is a fundamental process in many areas including computer graphics and medical applications. Different hierarchical acceleration structures for ray tracing have been developed. Such ray tracing approaches executed on advanced many-core processors such as GPU, however, turns out to be memory bounded due to their frequent search operations in the hierarchical structures. This paper pr...
متن کاملBART: A Benchmark for Animated Ray Tracing
Due to the advent of ray tracing at interactive speeds and because there is an absence of a way to measure and compare performance and quality of ray traced scenes that are animated, we present an organized way to do this objectively and accurately in this proposal for BART: A Benchmark for Animated Ray Tracing. This is a suite of test scenes, placed in the public domain, designed to stress ray...
متن کامل