Ray Tracing

This program implements the core algorithm of sequential ray-tracing. Instead of using ray transfer matrix (a.k.a. ABCD matrix), this program uses differential geometry, which can cope with any parameterizable surfaces.

Installation and build

The following install procedures only tested on Ubuntu Linux

Clone this repo with --recurse-submodules
Download BOOST library
Add cmake parameter -DBOOST_ROOT=/your/boost/library
Download and add Eigen library
Install plplot: sudo apt-get install libplplot-dev pkg-config --cflags --libs plplot-c++
Install yaml-cpp:
- Download yaml-cpp
- Make a ./build directory
- Run cmake ..
- Run make and then sudo make install. or sudo apt-get install libyaml-cpp-dev

Dependencies

This software builds with googletest and eigen, please make sure you add --recurse-submodules when cloning the repo, i.e.,

git clone https://github.com/kanhua/cpp-raytracing.git --recurse-submodules

This software requires the following external libraries

Boost

Download Boost and set -DBOOST_ROOT=/your/boost/library when running cmake.

plplot

Use apt-get: sudo apt-get install libplplot-dev then check if the package exists by: pkg-config --cflags --libs plplot-c++ or pkg-config --cflags --libs plplotd-c++

yaml-cpp

Use sudo apt-get install libyaml-cpp-dev

Alternatively:

Downlaod yaml-cpp
Make a ./build directory
Run cmake ..
Run make and then sudo make install.

Build

In the root folder of this repo:

mkdir build
cd build
cmake ..
make

Run the program

In build directory, run the command cpp-raytracing using the following usage

./cpp_raytracing [config_filename]

config_filename is a yaml file that sets the lenses and the rays parameters for the program to run.

For example, if the executable sits in build/ directory in project root folder, you can type:

./cpp_raytracing ../examples/single_biconvex_lens.yaml

Upon successful run, this program should generate a SVG file that plots the ray tracing results. You can try other example yaml files in examples/ folder.

Project structure

The entry class of the simulation is OpticalSystem, which consists of vectors of OpticalRays and AsphericSurfaces. AsphericSurfaces class manages the shape of the lens surfaces; OpticalRays records the paths of each light rays. The key algorithm of this program occurs in AsphericSurface::intersect(OpticalRay &ray, const_refractive_index_functor prev_n), which calculates the intersection between a ray and a lens surface, and then calculates the refracted path after that.

Then, the simulated data is plotted by PlPlot library via the wrapper PLStreamWrapper.