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BiDirectional Path Tracing
 PROCEEDINGS OF THIRD INTERNATIONAL CONFERENCE ON COMPUTATIONAL GRAPHICS AND VISUALIZATION TECHNIQUES (COMPUGRAPHICS ’93
, 1993
"... In this paper we present a new Monte Carlo rendering algorithm that seamlessly integrates the ideas of ..."
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Cited by 125 (10 self)
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In this paper we present a new Monte Carlo rendering algorithm that seamlessly integrates the ideas of
Clustering for Glossy Global Illumination
 ACM TRANSACTIONS ON GRAPHICS
, 1997
"... We present a new clustering algorithm for global illumination in complex environments. The new algorithm extends previous work on clustering for radiosity to allow for nondiffuse (glossy) reflectors. We represent clusters as points with directional distributions of outgoing and incoming radiance and ..."
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Cited by 62 (4 self)
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We present a new clustering algorithm for global illumination in complex environments. The new algorithm extends previous work on clustering for radiosity to allow for nondiffuse (glossy) reflectors. We represent clusters as points with directional distributions of outgoing and incoming radiance and importance, and we derive an error bound for transfers between these clusters. The algorithm groups input surfaces into a hierarchy of clusters, and then permits clusters to interact only if the error bound is below an acceptable tolerance. We show that the algorithm is asymptotically more efficient than previous clustering algorithms even when restricted to ideally diffuse environments. Finally, we demonstrate the performance of our method on two complex glossy environments.
QuasiMonte Carlo Radiosity
, 1996
"... The problem of global illumination in computer graphics is described by a second kind Fredholm integral equation. Due to the complexity of this equation, Monte Carlo methods provide an interesting tool for approximating solutions to this transport equation. For the case of the radiosity equation, w ..."
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Cited by 39 (2 self)
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The problem of global illumination in computer graphics is described by a second kind Fredholm integral equation. Due to the complexity of this equation, Monte Carlo methods provide an interesting tool for approximating solutions to this transport equation. For the case of the radiosity equation, we present the deterministic method of quasirandom walks. This method very efficiently uses low discrepancy sequences for integrating the Neumann series and consistently outperforms stochastic techniques. The method of quasirandom walks also is applicable to transport problems in settings other than computer graphics.
An Integral Geometry Based Method for Fast FormFactor Computation
 Computer Graphics Forum (Eurographics
, 1993
"... Monte Carlo techniques have been widely used in rendering algorithms for local integration. For example, to compute the contribution of a patch to the luminance of another. In the present paper we propose an algorithm based on Integral geometry where Monte Carlo is applied globally. We give some res ..."
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Cited by 31 (16 self)
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Monte Carlo techniques have been widely used in rendering algorithms for local integration. For example, to compute the contribution of a patch to the luminance of another. In the present paper we propose an algorithm based on Integral geometry where Monte Carlo is applied globally. We give some results of the implementation to validate the proposition and we study the error of the technique, as well as its complexity. 1. INTRODUCTION Monte Carlo methods in radiative heat transfer, and thereafter in radiosity, can be classified in two: those that ignore the formfactor matrix and only need a final solution, and those which explicitly give the form factor matrix and solve a posteriori the equations system. [Shamsundar73], [Pattanaik92] and [Shirley90] fall into the first category, while [Weiner65] belongs to the second. The first category is more suitable for a quick solution, while the second allows the possibility of changing the problem's initial conditions of illumination. As [Sie...
Efficient glossy global illumination with interactive viewing
 In Graphics Interface 1999. Canadian HumanComputer Communications Society
, 1999
"... The ability to perform interactive walkthroughs of global illumination solutions including glossy effects is a challenging open problem. In this paper we overcome certain limitations of previous approaches. We first introduce a novel, memory and computeefficient representation of incoming illumina ..."
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Cited by 29 (8 self)
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The ability to perform interactive walkthroughs of global illumination solutions including glossy effects is a challenging open problem. In this paper we overcome certain limitations of previous approaches. We first introduce a novel, memory and computeefficient representation of incoming illumination, in the context of a hierarchical radiance clustering algorithm. We then represent outgoing radiance with an adaptive hierarchical basis, in a manner suitable for interactive display. Using appropriate refinement and display strategies, we achieve walkthroughs of glossy solutions at interactive rates for nontrivial scenes. In addition, our implementation has been developed to be portable and easily adaptable as an extension to existing, diffuseonly, hierarchical radiosity systems. We present results of the implementation of glossy global illumination in two independent global illumination systems.
The use of global random directions to compute radiosity. Global Monte Carlo techniques.
, 1996
"... Contents Acknowledgements 3 Foreword 9 1 Introduction 11 2 PreviousWork 14 2.1 The Radiosity equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 2.1.1 Rendering Equation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 2.1.2 Rendering Equation for diffuse ..."
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Cited by 28 (16 self)
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Contents Acknowledgements 3 Foreword 9 1 Introduction 11 2 PreviousWork 14 2.1 The Radiosity equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 2.1.1 Rendering Equation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 2.1.2 Rendering Equation for diffuse surfaces . . . . . . . . . . . . . . . . . . . . 16 2.1.3 The Radiosity system of equations . . . . . . . . . . . . . . . . . . . . . . . 17 2.1.4 Two forms of the Form Factor integral . . . . . . . . . . . . . . . . . . . . . 18 2.1.5 The Form Factor integral as a contour integral . . . . . . . . . . . . . . . . 18 2.1.6 Differential area to area Form Factor . . . . . . . . . . . . . . . . . . . . . . 19 2.2 Computing the Form Factor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 2.2.1 Deterministic numerical solutions . . . . . . . . . . . . . . . . . . . . . . . . 22 2.3 Monte Carlo evaluation of the Form Factor integral . . . . . . . . . . . . . . . . .
Using the Modified Phong Reflectance Model for Physically Based Rendering
, 1994
"... This text discusses a few aspects of reflectance models in physically based rendering: ffl The first section presents the definition of the bidirectional reflection distribution function (brdf) of a surface and its physical properties. ffl On a more practical level, the next section discusses mode ..."
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Cited by 25 (0 self)
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This text discusses a few aspects of reflectance models in physically based rendering: ffl The first section presents the definition of the bidirectional reflection distribution function (brdf) of a surface and its physical properties. ffl On a more practical level, the next section discusses models to represent brdfs and their desired properties in general for Monte Carlo algorithms. ffl The third section goes into details about a specific reflectance model, the modified Phong brdf, with its definition, its properties and its use. We show how this model can be correctly integrated in importance sampling schemes for physically based Monte Carlo rendering algorithms. ffl The fourth section is devoted to alternative parameter spaces in which reflectance models can be sampled, either deterministically or stochastically. ffl The last section discusses an important implementational issue, more specifically the problem of verifying the implementation of a reflectance model. Keywords : ...
Importance Driven Construction of Photon Maps
 In Rendering Techniques ’98 (Proceedings of the 9th Eurographics Workshop on Rendering
, 1998
"... . Particle tracing allows physically correct simulation of all kinds of light interaction in a scene, but can be a computationally expensive task. Use of visual importance is a powerful technique to improve the efficiency of global illumination calculations. We describe a three pass solution for glo ..."
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Cited by 22 (0 self)
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. Particle tracing allows physically correct simulation of all kinds of light interaction in a scene, but can be a computationally expensive task. Use of visual importance is a powerful technique to improve the efficiency of global illumination calculations. We describe a three pass solution for global illumination calculation extending the two pass approach proposed by Jensen. In the first pass particle tracing of importance is performed to create a global data structure, called importance map. Based on this data structure importance driven photon tracing is used in the second pass to construct a photon map containing information about the global illumination in the scene. In the last pass the image is rendered by distributed ray tracing using the photon map. The photon tracing process, improved by the use of importance information, creates photon maps with an up to 8times higher photon density in important regions of the scene. This allows a better use of memory and computation time...
The potential equation and importance in illumination computations
 Computer Graphics Forum
, 1993
"... An equation adjoint tothe luminance equation for describing the global illumination can be formulated using the notion of a surface potential to illuminate the region of interest. This adjoint equation which we shall call as the potential equation, is fundamental to the adjoint radiosity equation us ..."
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Cited by 18 (2 self)
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An equation adjoint tothe luminance equation for describing the global illumination can be formulated using the notion of a surface potential to illuminate the region of interest. This adjoint equation which we shall call as the potential equation, is fundamental to the adjoint radiosity equation used to devise the importance driven radiosity algorithm. In this paper we rst brie y derive the adjoint system of integral equations and then show that the adjoint linear equations used in the above algorithm are basically discrete formulations of the same. We also show that the importance entity of the linear equations is basically the potential function integrated over a patch. Further we prove that the linear operators in the two equations are indeed transposes of each other. 1.
Efficient Importance Sampling Techniques for the Photon Map
, 2000
"... In global illumination computations the photon map is a powerful tool for approximating the irradiance, which is stored independent from scene geometry. By presenting a new algorithm, which uses novel importance sampling techniques, we improve the memory footprint of the photon map, simplify the cau ..."
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Cited by 18 (4 self)
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In global illumination computations the photon map is a powerful tool for approximating the irradiance, which is stored independent from scene geometry. By presenting a new algorithm, which uses novel importance sampling techniques, we improve the memory footprint of the photon map, simplify the caustic generation, and allow for a much faster sampling of direct illumination in complicated models as they arise in a production environment.