RobinTrace

RobinTrace is a sequential raytracing API for optical design. It is implemented in C++.

Development roadmap

We follow a roughly bottom-up development approach. The approximate current roadmap is the following.

• ✅ RobinTrace (core): Done. API and features will continue to evolve.
• ✅ rbt-samplings: Done. New samplings and features will be added as the need arises.
• ⚙️ Render: 90% done. 3D rendering of optical parts and ray results.
• 💭 High-level optical systems class: In definition. This is the description of optical systems in a format familiar to optical designers. This includes interfaces to save and load optical system files.
• 💭 Ray-aiming: In definition. This allows defining optical systems with an aperture stop at an arbitrary optical part. Different kinds of solutions exist, we are still in the process of fleshing out how the API will look.
• 💭 Optical systems interface with optimization engines. Devise the tools for defining a callable interface with inputs and objectives.
• Milestone 1: RobinTrace is able to robustly optimize any kind of simple optical system.
• 💭 Freeform optical parts: adding freeform surfaces to the core engine. We delay this addition because of the potential complexity it introduces.
• 💭 Differential raytracing: Add "automatic" differentiation to raytracing, probably with autodiff. This has applications in using optimization engines which make use of derivatives data. This also can help with ray-aiming.
• 💭 Performance overhaul and multithreading/GPU work. The idea is to take advantage of multi-core CPU and GPU. The parallelization will probably happen at the optimization engine interface. Opportunities to use GPU are not identified at this time.

Documentation

Please refer to the Doxygen documentation (in progress).

In addition, the submodule poaky has its own LaTeX documentation. It documents mainly the mathematical formulation of the operations and the corresponding rationale. The API is documented in the doxygen documentation. The report can be compiled from the LaTeX files in latex-poaky. A compiled version is edited at Poaky documentation PDF.

Build

RobinTrace is configured with cmake. By default, only the library is built. You can enable executable targets by setting the corresponding options.

Switch to a /build directory at the root of the project folder. Run:

cmake -Drobintrace_build_example=ON
      -Drobintrace_build_tests=ON
      -Drobintrace_build_coverage=ON
      -Drobintrace_build_benchmark=ON
      ..

This will download the dependencies and prepare the build targets. The build targets are the following:

• robintrace_example: Example file for robintrace usage.
• robintrace_test: Test suite.
• robintrace_benchmark: Benchmark suite.
• robintrace_coverage_report: Code coverage report of the test suite. The report may be consulted at build/robintrace_coverage_report/index.html.

Dependencies

We use the following libraries:

• Eigen3.

They are downloaded automatically (from online repositories) through CMake when configuring.

In addition, only for tests:

• Catch2
• Boost

Licensing

The software is licensed under MIT, the documentation under CC-BY.