This dataset contains six examples in our paper, 
Downsampling Scattering Parameters for Rendering Anisotropic Media.

Our code is based on Mitsuba 0.5.0. After building Mitsuba, 
you can start rendering by 'mitsuba twill_homo.xml' for example.

There are several different types of volumes for heterogeneous medium.
-- density: 1-channel float32 volume, representing densities.
-- albedo: 3-channel float32 volume, representing (r, g, b) colors.
-- segment: 1-channel float32 volume, representing voxel clustering indices 
   (0..num_voxel_clusters).

For SGGX phase functions,
-- cdf_{0..num_sggx_lobes-1}: 1-channel float32 volume, representing cumulative probability
   for each lobe.
-- s1_{0..num_sggx_lobes-1}: 3-channel float32 volume, representing (Sxx, Syy, Szz).
-- s2_{0..num_sggx_lobes-1}: 3-channel float32 volume, representing (Sxy, Sxz, Syz).
The SGGX matrix is written as
[Sxx  Sxy  Sxz;
 Sxy  Syy  Syz;
 Sxz  Syz  Szz]

If you have any questions, feel free to contact Lifan Wu (winmad.wlf@gmail.com).
