Scattering from Elliptical Hair Fibers Based on Microfacet Theory implemented in Mitsuba 2

⚠️ This repository is not maintained. For up-to-date version, please check the implementation in Blender, which includes improvements such as a near-field extension, reduced energy loss by accounting multiple scattering and a TRRT+ lobe, as well as a few simplified computation and bug fixes.

Overview

This code base includes the implementation of the SIGGRAPH 2022 poster Scattering from Elliptical Hair Fibers Based on Microfacet Theory in Mitsuba 2.

Instruction

• Clone the Mitsuba Renderer 2 repository.
• Copy the current folder to the repository.
• Add this line to src/bsdfs/CMakeLists.txt:

  add_plugin(roughhair            roughhair.cpp)

  Add to src/shapes/CMakeLists.txt:

  add_plugin(hair             hair.cpp)
  add_plugin(hairsegment      hairsegment.cpp)

  Then compile as instructed in the Mitsuba 2 Docs.

  Usage

  in the build folder, execute dist/mitsuba ../hair_scenes/xxx.xml

  Note

• In Mitsuba 2, $\omega_i$ denotes the camera ray and $\omega_o$ the light ray. Therefore, for elliptical cross-sections, these two components are swapped in roughhair.cpp.
• This repository is the same as https://github.com/RiverIntheSky/roughhair/tree/ellipse