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214
Pipeline Rendering: Interaction And Realism Through HardwareBased MultiPass Rendering
, 1996
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A Beam Tracing Method for Interactive Architectural Acoustics
, 2003
"... A difficult challenge in geometrical acoustic modeling is computing propagation paths from sound sources to receivers fast enough for interactive applications. We paper describe a beam tracing method that enables interactive updates of propagation paths from a stationary source to a moving receiv ..."
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Cited by 60 (4 self)
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A difficult challenge in geometrical acoustic modeling is computing propagation paths from sound sources to receivers fast enough for interactive applications. We paper describe a beam tracing method that enables interactive updates of propagation paths from a stationary source to a moving receiver. During a precomputation phase, we trace convex polyhedral beams from the location of each sound source, constructing a "beam tree" representing the regions of space reachable by potential sequences of transmissions, diffractions, and specular reflections at surfaces of a 3D polygonal model. Then, during an interactive phase, we use the precomputed beam trees to generate propagation paths from the source(s) to any receiver location at interactive rates. The key features of our beam tracing method are: 1) it scales to support large architectural environments, 2) it models propagation due to wedge diffraction, 3) it finds all propagation paths up to a given termination criterion without exhaustive search or risk of undersampling, and 4) it updates propagation paths at interactive rates. We demonstrate use of this method for interactive acoustic design of architectural environments.
Radiance Interpolants for Accelerated BoundedError Ray Tracing
 ACM Transactions on Graphics
, 1999
"... this paper, we present a system that exploits objectspace, rayspace, imagespace and temporal coherence to accelerate ray tracing. Our system uses persurface interpolants to approximate radiance, while conservatively bounding error. The techniques we introduce in this paper should enhance both int ..."
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Cited by 58 (6 self)
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this paper, we present a system that exploits objectspace, rayspace, imagespace and temporal coherence to accelerate ray tracing. Our system uses persurface interpolants to approximate radiance, while conservatively bounding error. The techniques we introduce in this paper should enhance both interactive and batch ray tracers.
Ray differentials and multiresolution geometry caching for distribution ray tracing in complex scenes
 In Eurographics 2003
, 2003
"... When rendering only directly visible objects, ray tracing a few levels of specular reflection from large, lowcurvature surfaces, and ray tracing shadows from pointlike light sources, the accessed geometry is coherent and a geometry cache performs well. But in many other cases, the accessed geometry ..."
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Cited by 37 (6 self)
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When rendering only directly visible objects, ray tracing a few levels of specular reflection from large, lowcurvature surfaces, and ray tracing shadows from pointlike light sources, the accessed geometry is coherent and a geometry cache performs well. But in many other cases, the accessed geometry is incoherent and a standard geometry cache performs poorly: ray tracing of specular reflection from highly curved surfaces, tracing rays that are many reflection levels deep, and distribution ray tracing for wide glossy reflection, global illumination, wide soft shadows, and ambient occlusion. Fortunately, less geometric accuracy is necessary in the incoherent cases. This observation can be formalized by looking at the ray differentials for different types of scattering: coherent rays have small differentials, while incoherent rays have large differentials. We utilize this observation to obtain efficient multiresolution caching of geometry and textures (including displacement maps) for classic and distribution ray tracing in complex scenes. We use an existing multiresolution caching scheme (originally developed for scanline rendering) for textures and displacement maps, and introduce a multiresolution geometry caching scheme for tessellated surfaces. The multiresolution geometry caching scheme makes it possible to efficiently render scenes that, if fully tessellated, would use 100 times more memory than the geometry cache size. 1.
A comprehensive theory of volumetric radiance estimation using photon points and beams
 ACM Transactions on Graphics
, 2011
"... We present two contributions to the area of volumetric rendering. We develop a novel, comprehensive theory of volumetric radiance estimation that leads to several new insights and includes all previously published estimates as special cases. This theory allows for estimating inscattered radiance at ..."
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Cited by 33 (13 self)
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We present two contributions to the area of volumetric rendering. We develop a novel, comprehensive theory of volumetric radiance estimation that leads to several new insights and includes all previously published estimates as special cases. This theory allows for estimating inscattered radiance at a point, or accumulated radiance along a camera ray, with the standard photon particle representation used in previous work. Furthermore, we generalize these operations to include a more compact, and more expressive intermediate representation of lighting in participating media, which we call “photon beams. ” The combination of these representations and their respective query operations results in a collection of nine distinct volumetric radiance estimates. Our second contribution is a more efficient rendering method for participating media based on photon beams. Even when shooting and storing less photons and using less computation time, our method significantly reduces both bias (blur) and variance in volumetric radiance estimation. This enables us to render sharp lighting details (e.g. volume caustics) using just tens of thousands of photon beams, instead of the millions to billions of photon points required with previous methods.
Adaptive Splatting for Specular to Diffuse Light Transport
 Proceedings of the 5th Eurographics Workshop on Rendering
, 1994
"... We present an extension to existing techniques to provide for more accurate resolution of specular to diffuse transfer within a global illumination framework. In particular this new model is adaptive with a view to capturing high frequency phenomena such as caustic curves in sharp detail and yet all ..."
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Cited by 29 (2 self)
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We present an extension to existing techniques to provide for more accurate resolution of specular to diffuse transfer within a global illumination framework. In particular this new model is adaptive with a view to capturing high frequency phenomena such as caustic curves in sharp detail and yet allowing for low frequency detail without compromising noise levels and aliasing artefacts. A 2pass raytracing algorithm is used, with an adaptive lightpass followed by a standard eyepass. During the lightpass, rays are traced from the light sources (essentially sampling the wavefront radiating from the sources), each carrying a fraction of the total power per wavelength of the source. The interactions of these rays with diffuse surfaces are recorded in ‘illuminationmaps’, as first proposed by Arvo [Arvo86]. The key to reconstructing the intensity gradients due to this lightpass lies in the construction of the illumination maps. We record the power carried by the ray as a ‘splat ’ of energy flux, deposited on the surface using a gaussian distribution kernel. The kernel of the splat is adaptively scaled according to an estimation of the wavefront divergence or convergence, thus resolving sharp intensity gradients in regions of high wavefront convergence and smooth gradients in areas of divergence. The 2nd pass eyetrace modulates the surface’s radiance according to the power stored in the illumination map in order to include the specular to diffuse light modelled during the first pass. 2.
A Realtime Beam Tracer with Application to Exact Soft Shadows
 EUROGRAPHICS SYMPOSIUM ON RENDERING (2007) JAN KAUTZ AND SUMANTA PATTANAIK (EDITORS)
, 2007
"... Efficiently calculating accurate soft shadows cast by area light sources remains a difficult problem. Ray tracing based approaches are subject to noise or banding, and most other accurate methods either scale poorly with scene geometry or place restrictions on geometry and/or light source size and s ..."
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Cited by 29 (5 self)
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Efficiently calculating accurate soft shadows cast by area light sources remains a difficult problem. Ray tracing based approaches are subject to noise or banding, and most other accurate methods either scale poorly with scene geometry or place restrictions on geometry and/or light source size and shape. Beam tracing is one solution which has historically been considered too slow and complicated for most practical rendering applications. Beam tracing’s performance has been hindered by complex geometry intersection tests, and a lack of good acceleration structures with efficient algorithms to traverse them. We introduce fast new algorithms for beam tracing, specifically for beam–triangle intersection and beam–kdtree traversal. The result is a beam tracer capable of calculating precise primary visibility and point light shadows in realtime. Moreover, beam tracing provides full area elements instead of point samples, which allows us to maintain coherence through to secondary effects and utilize the GPU for high quality antialiasing and shading with minimal extra cost. More importantly, our analysis shows that beam tracing is particularly well suited to soft shadows from area lights, and we generate essentially exact noisefree soft shadows for complex scenes in seconds rather than minutes or hours.
Geometric and Arithmetic Culling Methods for Entire Ray Packets
, 2006
"... Recent interactive ray tracing performance has been mainly derived from the use of ray packets. Larger ray packets allow for significant amortization of both computations and memory accesses; however, the majority of primitives are still intersected by each ray in a packet. This paper discusses seve ..."
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Cited by 23 (9 self)
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Recent interactive ray tracing performance has been mainly derived from the use of ray packets. Larger ray packets allow for significant amortization of both computations and memory accesses; however, the majority of primitives are still intersected by each ray in a packet. This paper discusses several methods to cull entire ray packets against common primitives (box, triangle, and sphere) that allows an arbitrary number of rays to be tested by a single test. This provides cheap “all miss ” or “all hit ” tests and may substantially improve the performance of an interactive ray tracer. The paper surveys current methods, provides details on three particular approaches using interval arithmetic, bounding planes, and corner rays, describes how the respective bounding primitives can be easily and efficiently constructed, and points out the relation among the different fundamental concepts.
Towards Interactive Photorealistic Rendering of Indoor Scenes: A Hybrid Approach
, 1999
"... . Photorealistic rendering methods produce accurate solutions to the rendering equation but are computationally expensive and typically noninteractive. Some researchers have used graphics hardware to obtain photorealistic effects but not at interactive frame rates. We describe a technique to achieve ..."
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Cited by 23 (1 self)
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. Photorealistic rendering methods produce accurate solutions to the rendering equation but are computationally expensive and typically noninteractive. Some researchers have used graphics hardware to obtain photorealistic effects but not at interactive frame rates. We describe a technique to achieve near photorealism of simple indoor scenes at interactive rates using both CPUs and graphics hardware in parallel. This allows the user the ability to interactively move objects and lights in the scene. Our goal is to introduce as many global illumination effects as possible while maintaining a high frame rate. We describe methods to generate soft shadows, approximate onebounce indirect lighting, and specular reflection and refraction effects. 1 Introduction and previous work Research in photorealistic rendering has concentrated on numerically solving the rendering equation[9]. Ray tracers[22] use Monte Carlo methods while radiosity systems[6] use finite element methods. These give accurat...
Path Differentials and Applications
 In Rendering Techniques 2001: 12th Eurographics Workshop on Rendering
, 2001
"... Photorealistic rendering algorithms such as Monte Carlo ray tracing sample individual paths to compute images. Noise and aliasing artefacts are usually reduced by supersampling. Knowledge about the neighborhood of the path, such as an estimated footprint, can be used to reduce these artefacts wi ..."
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Cited by 21 (0 self)
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Photorealistic rendering algorithms such as Monte Carlo ray tracing sample individual paths to compute images. Noise and aliasing artefacts are usually reduced by supersampling. Knowledge about the neighborhood of the path, such as an estimated footprint, can be used to reduce these artefacts without having to trace additional paths. The recently introduced ray differentials estimate such a footprint for classical ray tracing, by computing ray derivatives with respect to the image plane. The footprint proves to be useful for filtering textures locally on surfaces. In this paper, we generalize the use of these derivatives to arbitrary path sampling, including general reflection and refraction functions.