Microfacet Distribution Function: To Change or Not to Change, That Is the Question

In computer graphics and multimedia, bidirectional reflectance distribution function (BRDF) is commonly used for modeling the reflection and refraction of light. In this study, one of the important components of the reflectance models, namely, the microfacet distribution function (MDF) has been considered. The analytical MDFs allow only approximating the real distribution of the surface. Modern graphic software gives the opportunity to select the MDF that fits the real reflection in the best way. The question arises: can we really replace one MDF with another in this situation? And if it is possible, how to convert parameters from one function to the other. The problem is topical, important and practical—for all users of graphic software. In this article, various examples of MDF have been discussed. After RMSE analysis the mathematical dependencies that allow for the exchange of one MDF with the other have been proposed. In this study, consequences of applying different MDFs have been also discussed and comparison of the visual effect has

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