Accelerated path tracing in pure Ruby

README
Issues 2

Path tracer

Features

BVH acceleration
OBJ triangle mesh loading
Depth of field
Texture mapping
Antialiasing
Primitives
- Sphere
- Triangle
- Ground
Materials
- Lambertian
- Metal
- Diffuse light

Installation

rake install

Credits

Ray tracing book series by Peter Shirley [Book]
Ray tracing from ground up [Book]

0 Open More issues

Closed

Parallel processing

Using the parallel gem:

require 'parallel'

module PathTracer
  class Scene
    # ...

    def render(ns=1, file="output.ppm")
      puts "writing #{file}"

      # produce a 2d array of all pixels:
      pixels = ([email protected]).to_a.product(([email protected]).to_a)

      # use all CPU cores for the heavy lifting:
      data = Parallel.map(pixels) do |y,x|
        col = Vector[0, 0, 0]
        (1..ns).each do |s1|
          (1..ns).each do |s2|
            i = (x + (s1 - Random.rand) / ns) / @width.to_f
            j = (y + (s2 - Random.rand) / ns) / @height.to_f
            ray = @camera.ray(i, j)
            col += color(ray)
          end
        end

        percentage = (y * @width + x) * 100 / (@width * @height - 1)
        printf("\r[%-20s] %d%%", "=" * (percentage / 5), percentage)

        col /= (ns * ns).to_f
      end

      # Write the file as before...

Running on a 12 core linux box:

[nix-shell:~/src/path_tracer]$ time ruby -Ilib ./examples/cover.rb && convert cover.ppm cover.png
writing cover.ppm
[=================== ] 99%%
real	1m36.414s
user	17m6.289s
sys	0m3.612s

opened Aug 3, 2020 by emptyflask 2

Closed