Computer graphic rendering of 3 vases coated with colored metallic paint

Computer Graphic Rendering of Material Surfaces

Computer graphic rendering of painted samples in a light booth


One of the most general means to characterize the reflection properties of a surface is by use of the bi-directional reflection distribution function (BRDF), a function which defines the spectral and spatial reflection characteristic of a surface. The BRDF of a surface is the ratio of reflected radiance to incident irradiance at a particular wavelength:

\rho(\Theta_{i}; \Theta_{r}; \lambda) = \frac{dL_{r}(\Theta_{i}; \Theta_{r};\lambda)}{dE_{i}(\Theta_{i}; \lambda)}
where the subscripts i and r denote incident and reflected respectively, \Theta=(\theta,\phi) is the direction of light propagation, \lambda is the wavelength of light, L is radiance, and E is irradiance. The geometry used by the BRDF is shown below in Figure 1.

Figure 1: Light reflection geometry
Figure 1: Light reflection geometry


Measurement Science for Optical Reflectance and Scattering

Mathematical and Computational Sciences Division

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