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465
The rendering equation
 Computer Graphics
, 1986
"... ABSTRACT. We present an integral equation which generallzes a variety of known rendering algorithms. In the course of discussing a monte carlo solution we also present a new form of variance reduction, called Hierarchical sampling and give a number of elaborations shows that it may be an efficient n ..."
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Cited by 908 (0 self)
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ABSTRACT. We present an integral equation which generallzes a variety of known rendering algorithms. In the course of discussing a monte carlo solution we also present a new form of variance reduction, called Hierarchical sampling and give a number of elaborations shows that it may be an efficient new technique for a wide variety of monte carlo procedures. The resulting renderlng algorithm extends the range of optical phenomena which can be effectively simulated.
A Practical Model for Subsurface Light Transport
, 2001
"... This paper introduces a simple model for subsurface light transport in translucent materials. The model enables efficient simulation of effects that BRDF models cannot capture, such as color bleeding within materials and diffusion of light across shadow boundaries. The technique is efficient even fo ..."
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Cited by 339 (23 self)
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This paper introduces a simple model for subsurface light transport in translucent materials. The model enables efficient simulation of effects that BRDF models cannot capture, such as color bleeding within materials and diffusion of light across shadow boundaries. The technique is efficient even for anisotropic, highly scattering media that are expensive to simulate using existing methods. The model combines an exact solution for single scattering with a dipole point source diffusion approximation for multiple scattering. We also have designed a new, rapid imagebased measurement technique for determining the optical properties of translucent materials. We validate the model by comparing predicted and measured values and show how the technique can be used to recover the optical properties of a variety of materials, including milk, marble, and skin. Finally, we describe sampling techniques that allow the model to be used within a conventional ray tracer.
The radiance lighting simulation and rendering system
 In Proceedings of SIGGRAPH 94, ACM SIGGRAPH / ACM
, 1994
"... This paper describes a physicallybased rendering system tailored to the demands of lighting design and architecture. The simulation uses a lightbackwards raytracing method with extensions to efficiently solve the rendering equation under most conditions. This includes specular, diffuse and direct ..."
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Cited by 296 (8 self)
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This paper describes a physicallybased rendering system tailored to the demands of lighting design and architecture. The simulation uses a lightbackwards raytracing method with extensions to efficiently solve the rendering equation under most conditions. This includes specular, diffuse and directionaldiffuse reflection and transmission in any combination to any level in any environment, including complicated, curved geometries. The simulation blends deterministic and stochastic raytracing techniques to achieve the best balance between speed and accuracy in its local and global illumination methods. Some of the more interesting techniques are outlined, with references to more detailed descriptions elsewhere. Finally, examples are given of successful applications of this free software by others. CR Categories: I.3.3 [Computer Graphics]: Picture/image generation Display algorithms; I.3.7 [Computer Graphics]:
Optical models for direct volume rendering
 IEEE Transactions on Visualization and Computer Graphics
, 1995
"... ..."
Global Illumination using Photon Maps
, 1996
"... This paper presents a two pass global illumination method based on the concept of photon maps. It represents a significant improvement of a previously described approach both with respect to speed, accuracy and versatility. In the first pass two photon maps are created by emitting packets of energy ..."
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Cited by 275 (9 self)
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This paper presents a two pass global illumination method based on the concept of photon maps. It represents a significant improvement of a previously described approach both with respect to speed, accuracy and versatility. In the first pass two photon maps are created by emitting packets of energy (photons) from the light sources and storing these as they hit surfaces within the scene. We use one high resolution caustics photon map to render caustics that are visualized directly and one low resolution photon map that is used during the rendering step. The scene is rendered using a distribution ray tracing algorithm optimized by using the information in the photon maps. Shadow photons are used to render shadows more efficiently and the directional information in the photon map is used to generate optimized sampling directions and to limit the recursion in the distribution ray tracer by providing an estimate of the radiance on all surfaces with the exception of specular...
RENDERING FUR WITH THREE DIMENSIONAL TEXTURES
, 1989
"... We present a method for rendering scenes with fine detail via an object called a texel, a rendering primitive inspired by volume densities mixed with anisotropic lighting models. This technique solves a long outstanding problem in image synthesis: the rendering of furry surfaces. ..."
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Cited by 264 (0 self)
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We present a method for rendering scenes with fine detail via an object called a texel, a rendering primitive inspired by volume densities mixed with anisotropic lighting models. This technique solves a long outstanding problem in image synthesis: the rendering of furry surfaces.
Interactive Rendering with Coherent Ray Tracing
 Computer Graphics Forum
, 2001
"... For almost two decades researchers have argued that ray tracing will eventually become faster than the rasterization technique that completely dominates todays graphics hardware. However, this has not happened yet. Ray tracing is still exclusively being used for offline rendering of photorealistic ..."
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Cited by 251 (56 self)
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For almost two decades researchers have argued that ray tracing will eventually become faster than the rasterization technique that completely dominates todays graphics hardware. However, this has not happened yet. Ray tracing is still exclusively being used for offline rendering of photorealistic images and it is commonly believed that ray tracing is simply too costly to ever challenge rasterizationbased algorithms for interactive use. However, there is hardly any scientific analysis that supports either point of view. In particular there is no evidence of where the crossover point might be, at which ray tracing would eventually become faster, or if such a point does exist at all.
Metropolis Light Transport
 Computer Graphics (SIGGRAPH '97 Proceedings
, 1997
"... We present a new Monte Carlo method for solving the light transport problem, inspired by the Metropolis sampling method in computational physics. To render an image, we generate a sequence of light transport paths by randomly mutating a single current path (e.g. adding a new vertex to the path). Eac ..."
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Cited by 212 (1 self)
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We present a new Monte Carlo method for solving the light transport problem, inspired by the Metropolis sampling method in computational physics. To render an image, we generate a sequence of light transport paths by randomly mutating a single current path (e.g. adding a new vertex to the path). Each mutation is accepted or rejected with a carefully chosen probability, to ensure that paths are sampled according to the contribution they make to the ideal image. We then estimate this image by sampling many paths, and recording their locations on the image plane. Our algorithm is unbiased, handles general geometric and scattering models, uses little storage, and can be orders of magnitude more e#cient than previous unbiased approaches. It performs especially well on problems that are usually considered di#cult, e.g. those involving bright indirect light, small geometric holes, or glossy surfaces. Furthermore, it is competitive with previous unbiased algorithms even for relatively simple ...
Generating antialiased images at low sampling densities
 In SIGGRAPH ’87: Proceedings of the 14th annual conference on Computer graphics and interactive techniques, ACM
, 1987
"... Ray tracing produces point samples of an image from a 3D model. Constructing an antialiased digital picture from point samples is difficult without resorting to extremely high sampling densities. This paper describes a program that focuses on that problem. While it is impossible to totally eliminat ..."
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Cited by 187 (7 self)
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Ray tracing produces point samples of an image from a 3D model. Constructing an antialiased digital picture from point samples is difficult without resorting to extremely high sampling densities. This paper describes a program that focuses on that problem. While it is impossible to totally eliminate aliasing, it has been shown that nonuniform sampling yields aliasing that is less conspicuous to the observer. An algorithm is presented for fast generation of nonuniform sampling patterns that are optimal in some sense. Some regions of an image may require extra sampling to avoid strong aliasing. Deciding where to do extra sampling can be guided by knowledge of how the eye perceives noise as a function of contrast and color. Finally, to generate the digital picture, the image must be reconstructed from the samples and resampled at the display pixel rate. The nonuniformity of the samples complicates this process, and a new nonuniform reconstruction filter is presented which solves this problem efficiently. This paper was presented in SIGGRAPH 87.
Predicting reflectance functions from complex surfaces
, 1992
"... This thesis describes a physicallybased Monte Carlo technique for approximating bidirectional reflectance distribution functions (BRDFs) for a large class of geometries by directly simulating geometric optical scattering from surfaces. The method is more general than previous analytical models: it ..."
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Cited by 179 (6 self)
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This thesis describes a physicallybased Monte Carlo technique for approximating bidirectional reflectance distribution functions (BRDFs) for a large class of geometries by directly simulating geometric optical scattering from surfaces. The method is more general than previous analytical models: it removes most restrictions on surface microgeometry. Three main points are described: a new representation of the BRDF, a Monte Carlo technique to estimate the coefficients of the representation, and the means of creating a milliscale BRDF from microscale scattering events. The combination of these techniques allows the prediction of scattering from essentially arbitrary roughness geometries. The BRDF is concisely represented by a matrix of spherical harmonic coefficients; the matrix is directly estimated from a geometric optics simulation, enforcing exact reciprocity. Microscale scattering events are represented by direct simulation (e.g., specular reflection and transmission by individual textile fibers) or by a microscaleaveraged model (e.g., a waveopticsbased statistical BRDF) depend