Graphics Reference
In-Depth Information
asymmetry, etc. Although the work is still in its early stages, it shows that the
dipole model is not the only practical option for modeling multiple scattering
even in homogeneous materials.
Image-based approaches offer another possibility for representing the effects
of subsurface scattering. As is described in Chapter 5, image-based rendering
starts with an acquired image that already contains effects such as subsurface
scattering. However, an image-based approach does not provide a model for scat-
tering, because there are no parameters to control so there is no direct way to
adjust the scattering to achieve the desired effects. The recent paper “SubEdit: A
Representation for Editing Measured Heterogeneous Subsurface Scattering” by
Ying Song, Xin Tong, Fabio Pellacini, and Pieter Peers [Song et al. 09] suggests
one interesting way around this. The idea is to decouple the nonlocal scattering
effects from the local properties and allow them to be edited. The results seem
promising and may lead to a general image-based subsurface scattering model.
It is typical in computer graphics for the first incarnation of a new technique or
innovation to be aimed at something specific. Generalization comes in a second
stage, after the new technique is widely applied and its advantages and limitations
are better understood. It could be said that the progress of subsurface scattering
is now beginning this second stage.
