## Using the Modified Phong Reflectance Model for Physically Based Rendering (1994)

Citations: | 25 - 0 self |

### BibTeX

@TECHREPORT{Lafortune94usingthe,

author = {Eric P. Lafortune and Yves D. Willems},

title = {Using the Modified Phong Reflectance Model for Physically Based Rendering},

institution = {},

year = {1994}

}

### Years of Citing Articles

### OpenURL

### Abstract

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 : ...

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Citation Context ...tion [15]. 3 3 The modified Phong reflectance model 3.1 Definition In 1975 Phong introduced a shading model which returns a colour for a point on a surface in the presence of some point light sources =-=[16]-=-. While the model does not have a physical basis and cannot be used as a brdf as it is, a physically plausible brdf which is very similar to the shading model is commonly used in rendering algorithms ... |

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Citation Context ...o reflect or absorb an incoming ray at a surface depend on it [14, 9, 10, 11, 12, 13]. Another application is the use of an ambient term times the brdf as a control variate for the rendering equation =-=[15]-=-. 3 3 The modified Phong reflectance model 3.1 Definition In 1975 Phong introduced a shading model which returns a colour for a point on a surface in the presence of some point light sources [16]. Whi... |