ialxn/rt

Multi-threaded Monte-Carlo geometric ray tracer

rt

A multi-threaded Monte-Carlo geometric ray tracer to calculate the spectrally resolved flux density distribution on targets. This is not about nicely rendering scenes like does POV-Ray. Details see the supplied (sparse) documentation and the examples given.

Installation

Requirements

gcc
libconfig
gsl
BLAS library
Geomview (or similar to visualize scene from OFF files)

Download zip and extract or clone repository. From the resulting folder run

$ xmkmf -a
$ make

Usage

$ rt -h

rt Version: v2.1-dirty  (2017-01-25) released by <Ivo Alxneit> [email protected]

Usage: rt
       --append, -a      append to output files. new seed must be given.
       --keep_closed, -k keep output files closed. [keep open].
       --Log, -L         log path of first n rays per source [0].
                         Raw format used.
       --log, -l         log path of first l rays per source [0].
                         OFF format used.
       --mode, -m        select run mode [0].
                         0: check and print input.
                         1: output geometry (OFF files).
                         2: run simulation.
       --threads, -t     number of threads to use [1]
       --Version, -V     Print version number
       --help, -h        Print this help message

Or with one of the provided tests.

Validate input:

$ rt < test_screen.cfg
seed = 1234;
P_factor = 0.0001;
sources = ( 
  {
    name = "s_1";
    type = "uniform point source";
    origin = [ 0.0, 0.0, 1.0 ];
    power = 10.0;
    spectrum = "lamp_spec_1.dat";
  }, 
  {
    name = "s_2";
    type = "uniform point source";
    origin = [ 0.0, 1.0, 1.0 ];
    power = 50.0;
    spectrum = "lamp_spec_1.dat";
  } );
targets = ( 
  {
    name = "screen1";
    type = "two-sided plane screen";
    point = [ 0.0, 0.5, 1.0 ];
    normal = [ 0.0, 1.0, 0.0 ];
    x = [ 1.0, 0.0, 0.0 ];
  }, 
  {
    name = "screen2";
    type = "one-sided plane screen";
    point = [ 0.0, 2.0, 1.0 ];
    normal = [ 0.0, -1.0, 0.0 ];
    x = [ 1.0, 0.0, 0.0 ];
  }, 
  {
    name = "screen3";
    type = "one-sided plane screen";
    point = [ 0.0, -1.0, 1.0 ];
    normal = [ 0.0, 1.0, 0.0 ];
    x = [ 1.0, 0.0, 0.0 ];
  }, 
  {
    name = "screen4";
    type = "one-sided plane screen";
    point = [ 0.0, 0.5, 0.0 ];
    normal = [ 0.0, 0.0, 1.0 ];
    x = [ 1.0, 0.0, 0.0 ];
  } );

Run it:

$ rt -m2 < test_screen.cfg
rt version v3.0 running ...
    2 sources initialized
    4 targets initialized
    using 1234 as seed for random number generator from config file
    one absorbed ray represents       0.0001 W
    using random number generator mt19937 from Gnu Scientific Library

        s_1 (uniform point source) started
            100000 rays to trace
            with total power of           10

        s_2 (uniform point source) started
            500000 rays to trace
            with total power of           50

  total number of rays traced: 600000
   total power of all sources:           60
    total number of rays lost: 600000
             total power lost:           60
total number of rays absorbed: 0
         total power absorbed:            0