RayTracer.jl

This package was written in the early days of Flux / Zygote. Both these packages have significantly improved over time. Unfortunately the current state of this package of has not been updated to reflect those improvements. It also seems that it might be better to gradually transition to AD systems like Diffractor (which will potentially have good support for mutations) / define the adjoints directly using ChainRules since Zygote will likely not be having these features (note there has not been an official announcement and the statement is based on some discussions in zulip forum)

A Ray Tracer written completely in Julia. This allows us to leverage the AD capablities provided by Zygote to differentiate through the Ray Tracer.

INSTALLATION

This package is registered. So open up a Julia 1.3+ repl and enter the pkg mode.

julia> ]
(v1.3) pkg> add RayTracer

To use the master branch (not recommended) do.

julia> ]
(v1.3) pkg> add RayTracer#master

TUTORIALS

Introductory Rendering Tutorial	Inverse Lighting Tutorial	Inverse Rendering with Optim.jl Tutorial

USAGE EXAMPLES

Follow the instructions below to run individual examples or use examples/script.sh to run all of them together.

First we need to get the versions of the packages used when these examples were written.

$ cd examples
$ julia --color=yes -e "using Pkg; Pkg.instantiate()"

Now we can run any of the file we need by julia --project=. --color=yes "/path/to/file"

Running Individual Examples

• teapot_rendering.jl -- We need to download the teapot.obj file.

wget https://raw.githubusercontent.com/McNopper/OpenGL/master/Binaries/teapot.obj

• performance_benchmarks.jl -- We need the mesh and texture for the yield sign board.

$ mkdir meshes
$ cd meshes
$ wget https://raw.githubusercontent.com/avik-pal/RayTracer.jl/master/test/meshes/sign_yield.obj
$ wget https://raw.githubusercontent.com/avik-pal/RayTracer.jl/master/test/meshes/sign_yield.mtl
$ cd ..

$ mkdir textures
$ cd textures
$ wget https://raw.githubusercontent.com/avik-pal/RayTracer.jl/master/test/textures/wood_osb.jpg
$ wget https://raw.githubusercontent.com/avik-pal/RayTracer.jl/master/test/textures/sign_yield.png
$ cd ..

This example requires a few arguments to be passes from command line. Chack them using

julia --project=. --color=yes "performance_benchmarks.jl" --help

• inverse_lighting.jl & optim_compatibility.jl -- We need to the tree.mtl and tree.obj files.

$ wget https://raw.githubusercontent.com/tejank10/Duckietown.jl/master/src/meshes/tree.obj 
$ wget https://raw.githubusercontent.com/tejank10/Duckietown.jl/master/src/meshes/tree.mtl

Additional Examples

Duckietown.jl uses RayTracer.jl for generating renders of a self-driving car environment. For more complex examples of RayTracer, checkout that project.

SUPPORTING AND CITING:

This software was developed as part of academic research. If you would like to help support it, please star the repository. If you use this software as part of your research, teaching, or other activities, we would be grateful if you could cite the following:

@article{Pal2020,
  doi = {10.21105/jcon.00037},
  url = {https://doi.org/10.21105/jcon.00037},
  year = {2020},
  publisher = {The Open Journal},
  volume = {1},
  number = {1},
  pages = {37},
  author = {Avik Pal},
  title = {RayTracer.jl: A Differentiable Renderer that supports Parameter Optimization for Scene Reconstruction},
  journal = {Proceedings of the JuliaCon Conferences}
}

CURRENT ROADMAP

These are not listed in any particular order

• [X] Add more types of common objects (use mesh rendering for this)
• [X] Add support for rendering arbitrary mesh
• [X] Inverse Rendering Examples
• [X] Texture Rendering
• [ ] Application in Machine Learning Models through Flux (work in progress)
• [ ] Major Overhaul using Flux3D.jl
• [ ] Exploit the latest improvements to Flux and Zygote