Ray Tracing

This codes performs ray tracing and computes the points where the rays intersect a geometry described by a stl file.

Installation

The depends on boost, Kokkos, and ArborX. You can configure ray_tracing using:

cmake \
  -D CMAKE_CXX_COMPILER=${KOKKOS_INSTALL_DIR}/bin/nvcc_wrapper \ 
  -D CMAKE_CXX_EXTENSIONS=OFF \
  -D CMAKE_PREFIX_PATH="${KOKKOS_INSTALL_DIR};${ARBORX_INSTALL_DIR};${BOOST_INSTALL_DIR}" \
${RAY_TRACING_SOURCE_DIR}

nvcc_wrapper is only necessary when using nvcc.

Usage

The code expects the following options:

• -s: the name of the STL file that contains the geometry
• -r: prefix of the ray file. The file name is expected to be of the form: ray_prefix-i.txt with i a number starting at zero.
• -n: number of ray files.
• -o: prefix of the output files. The file name is of the form output_prefix-i.txt or output_prefix-i.vtk
• -t: type of the output: csv, numpy (the array can be loaded using loadtxt), or vtk.

The format of the ray file is the following:

Number of rays
Coordinates of the ray origin  Direction of the ray

In practice, a file with three rays starting in (0,0,0) and following the axes x, y, and z will look as follows

3
0. 0. 0. 1. 0. 0.
0. 0. 0. 0. 1. 0.
0. 0. 0. 0. 0. 1.