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412
Multiresolution Modeling for Fast Rendering
 PROCEEDINGS OF GRAPHICS INTERFACE
, 1994
"... Three dimensional scenes are typically modeled using a single, fixed resolution model of each geometric object. Renderings of such a model are often either slow or crude, however: slow for distant objects, where the chosen detail level is excessive, and crude for nearby objects, where the detail lev ..."
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Cited by 114 (5 self)
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Three dimensional scenes are typically modeled using a single, fixed resolution model of each geometric object. Renderings of such a model are often either slow or crude, however: slow for distant objects, where the chosen detail level is excessive, and crude for nearby objects, where the detail level is insufficient. What is needed is a multiresolution model that represents objects at multiple levels of detail. With a multiresolution model, a rendering program can choose the level of detail appropriate for the object's screen size so that less time is wasted drawing insignificant detail. The principal challenge is the development of algorithms that take a detailed model as input and automatically simplify it, while preserving appearance. Multiresolution techniques can be used to speed many applications, including real time rendering for architectural and terrain simulators, and slower, higher quality rendering for entertainment and radiosity. This paper surveys existing multiresolutio...
Combining Hierarchical Radiosity and Discontinuity Meshing
, 1993
"... We introduce a new approach for the computation of viewindependent solutions to the diffuse global illumination problem in polyhedral environments. The approach combines ideas from hierarchical radiosity and discontinuity meshing to yield solutions that are accurate both numerically and visually. Fi ..."
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Cited by 110 (9 self)
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We introduce a new approach for the computation of viewindependent solutions to the diffuse global illumination problem in polyhedral environments. The approach combines ideas from hierarchical radiosity and discontinuity meshing to yield solutions that are accurate both numerically and visually. First, we describe a modified hierarchical radiosity algorithm that uses a discontinuitydriven subdivision strategy to achieve better numerical accuracy and faster convergence. Second, we present a new algorithm based on discontinuity meshing that uses the hierarchical solution to reconstruct an objectspace approximation to the radiance function that is visually accurate. Our results show significant improvements over both hierarchical radiosity and discontinuity meshing algorithms.
Lightcuts: a scalable approach to illumination
 ACM Transactions on Graphics (Proc. SIGGRAPH
, 2005
"... Lightcuts is a scalable framework for computing realistic illumination. It handles arbitrary geometry, nondiffuse materials, and illumination from a wide variety of sources including point lights, area lights, HDR environment maps, sun/sky models, and indirect illumination. At its core is a new alg ..."
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Cited by 109 (17 self)
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Lightcuts is a scalable framework for computing realistic illumination. It handles arbitrary geometry, nondiffuse materials, and illumination from a wide variety of sources including point lights, area lights, HDR environment maps, sun/sky models, and indirect illumination. At its core is a new algorithm for accurately approximating illumination from many point lights with a strongly sublinear cost. We show how a group of lights can be cheaply approximated while bounding the maximum approximation error. A binary light tree and perceptual metric are then used to adaptively partition the lights into groups to control the error vs. cost tradeoff. We also introduce reconstruction cuts that exploit spatial coherence to accelerate the generation of antialiased images with complex illumination. Results are demonstrated for five complex scenes and show that lightcuts can accurately approximate hundreds of thousands of point lights using only a few hundred shadow rays. Reconstruction cuts can reduce the number of shadow rays to tens.
ImageBased Rendering of Diffuse, Specular and Glossy Surfaces from a Single Image
, 2001
"... In this paper, we present a new method to recover an approximation of the bidirectional reflectance distribution function (BRDF) of the surfaces present in a real scene. This is done from a single photograph and a 3D geometric model of the scene. The result is a full model of the reflectance propert ..."
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Cited by 106 (1 self)
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In this paper, we present a new method to recover an approximation of the bidirectional reflectance distribution function (BRDF) of the surfaces present in a real scene. This is done from a single photograph and a 3D geometric model of the scene. The result is a full model of the reflectance properties of all surfaces, which can be rendered under novel illumination conditions with, for example, viewpoint modification and the addition of new synthetic objects. Our technique produces a reflectance model using a small number of parameters. These parameters nevertheless approximate the BRDF and allow the recovery of the photometric properties of diffuse, specular, isotropic or anisotropic textured objects. The input data are a geometric model of the scene including the light source positions and the camera properties, and a single image captured using this camera. Our algorithm generates a new synthetic image using classic rendering techniques, and a lambertian hypothesis about the reflectance model of the surfaces. Then, it iteratively compares the original image to the new one, and chooses a more complex reflectance model if the difference between the two images is greater than a userdefined threshold.
The Irradiance Volume
, 1996
"... This thesis presents a volumetric representation for the global illumination within a space based on the radiometric quantity irradiance. We call this representation the irradiance volume. Although irradiance is traditionally computed only for surfaces, its de nition can be naturally extended to all ..."
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Cited by 98 (8 self)
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This thesis presents a volumetric representation for the global illumination within a space based on the radiometric quantity irradiance. We call this representation the irradiance volume. Although irradiance is traditionally computed only for surfaces, its de nition can be naturally extended to all points and directions in space. The irradiance volume supports the reconstruction of believable approximations to the illumination in situations that overwhelm traditional global illumination algorithms. Atheoretical basis for the irradiance volume is discussed and the methods and issues involved with building the volume are described. The irradiance volume method is tested within several situations in which the use of traditional global illumination methods is impractical, and is shown to provide good performance.
Discontinuity Meshing for Radiosity
 Third Eurographics Workshop on Rendering
, 1992
"... The radiosity method is the most popular algorithm for simulating interreflection of light between diffuse surfaces. Most existing radiosity algorithms employ simple meshes and piecewise constant approximations, thereby constraining the radiosity function to be constant across each polygonal element ..."
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Cited by 96 (2 self)
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The radiosity method is the most popular algorithm for simulating interreflection of light between diffuse surfaces. Most existing radiosity algorithms employ simple meshes and piecewise constant approximations, thereby constraining the radiosity function to be constant across each polygonal element. Much more accurate simulations are possible if linear, quadratic, or higher degree approximations are used. In order to realize the potential accuracy of higherdegree approximations, however, it is necessary for the radiosity mesh to resolve discontinuities such as shadow edges in the radiosity function. A discontinuity meshing algorithm is presented that places mesh boundaries directly along discontinuities. Such algorithms offer the potential of faster, more accurate simulations. Results are shown for threedimensional scenes. Keywords: global illumination, diffuse interreflection, adaptive mesh, shadow. 1 Introduction One of the most challenging tasks of image synthesis in computer ...
Efficient Light Propagation for Multiple Anisotropic Volume Scattering
 In Proceedings of the 5th Eurographics Workshop on Rendering
, 1994
"... Realistic rendering of participating media like clouds requires multiple anisotropic light scattering. This paper presents a propagation approximation for light scattered into M direction bins, which reduces the "ray effect" problem in the traditional "discrete ordinates" method. ..."
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Cited by 80 (8 self)
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Realistic rendering of participating media like clouds requires multiple anisotropic light scattering. This paper presents a propagation approximation for light scattered into M direction bins, which reduces the "ray effect" problem in the traditional "discrete ordinates" method. For a regular grid volume of n 3 elements, it takes O(M n 3 log n + M 2 n 3 ) time and O(M n 3 + M 2 ) space. This document is reprinted from the proceedings of the Fifth Eurographics Workshop on Rendering, Darmstadt, Germany, June 13  15, 1994 1. Introduction To render realistic images of clouds, one must take into account absorption and multiple scattering of incoming illumination. In addition, to produce the bright edges surrounding a cloud when the sun is behind it, one must account for the anisotropic, mainly forward, scattering of light from the water droplets. In 1984, Jim Kajiya and Brian Von Herzen [Kaj84] proposed two methods for rendering clouds. The first was the twopass "slab" me...
Interactive Update Of Global Illumination Using A LineSpace Hierarchy
, 1997
"... Interactively manipulating the geometry of complex, globally illuminated scenes has to date proven an elusive goal. Previous attempts have failed to provide interactive updates of global illumination and have not been able to offer welladapted algorithms controlling the frame rate. The need for suc ..."
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Cited by 77 (10 self)
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Interactively manipulating the geometry of complex, globally illuminated scenes has to date proven an elusive goal. Previous attempts have failed to provide interactive updates of global illumination and have not been able to offer welladapted algorithms controlling the frame rate. The need for such interactive updates of global illumination is becoming increasingly important as the field of application of radiosity algorithms widens. To address this need, we present a novel algorithm which provides interactive update rates of global illumination for complex scenes with moving objects. In the context of clustering for hierarchical radiosity, we introduce the idea of an implicit linespace hierarchy. This hierarchy is realized by augmenting the links between hierarchical elements (clusters or surfaces) with shafts, representing the set of lines passing through the two linked elements. We show how linespace traversal allows rapid identification of modified links, and simultaneous clean...
Fast Computation of Shadow Boundaries Using Spatial Coherence and Backprojections
, 1994
"... This paper describes a fast, practical algorithm to compute the shadow boundariesin a polyhedral scene illuminated by a polygonal light source. The shadow boundaries divide the faces of the scene into regions such that the structure or "aspect" of the visible area of the light source is co ..."
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Cited by 76 (5 self)
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This paper describes a fast, practical algorithm to compute the shadow boundariesin a polyhedral scene illuminated by a polygonal light source. The shadow boundaries divide the faces of the scene into regions such that the structure or "aspect" of the visible area of the light source is constant within each region. The paper also describes a fast, practical algorithm to compute the structure of the visible light source in each region. Both algorithms exploit spatial coherence and are the most efficient yet developed. Given the structure of the visible light source in a region, queries of the form "What specific areas of the light source are visible?" can be answered almost instantly from any point in the region. This speeds up by several orders of magnitude the accurate computation of first level diffuse reflections due to an area light source. Furthermore, the shadow boundaries form a good initial decomposition of the scene for global illumination computations. CR category: I.3.7 [Co...
Interactive Global Illumination in Dynamic Scenes
 ACM Trans. Graphics
, 2002
"... In this paper, we present a system for interactive computation of global illumination in dynamic scenes. Our system uses a novel scheme for caching the results of a high quality pixelbased renderer such as a bidirectional path tracer. The Shading Cache is an objectspace hierarchical subdivision mes ..."
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Cited by 76 (8 self)
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In this paper, we present a system for interactive computation of global illumination in dynamic scenes. Our system uses a novel scheme for caching the results of a high quality pixelbased renderer such as a bidirectional path tracer. The Shading Cache is an objectspace hierarchical subdivision mesh with lazily computed shading values at its vertices. A high frame rate display is generated from the Shading Cache using hardwarebased interpolation and texture mapping. An image space sampling scheme refines the Shading Cache in regions that have the most interpolation error or those that are most likely to be affected by object or camera motion. Our system handles dynamic scenes and moving light sources efficiently, providing useful feedback within a few seconds and high quality images within a few tens of seconds, without the need for any precomputation. Our approach allows us to significantly outperform other interactive systems based on caching raytracing samples, especially in dynamic scenes. Based on our results, we believe that the Shading Cache will be an invaluable tool in lighting design and modelling while rendering.