A simple ray tracer and photon mapper that uses Phong's BRDF together with reflectant and refracting materials render 3D scenes using pure C++ without the need for extra libraries.
There are two live branches in this project.
- master -> The current branch, the render engine uses a photon mapping algorithm.
- ray_tracer -> The render engine uses a ray tracing algorithm.
The binary render is used as a showcase of some hardcoded scenes. It can handle the following 3D shapes:
- Spheres
- Planes
- Rectangles
- Triangles
- Boxes
- Triangle meshes (loaded from a cutdown version of .obj files)
- Menger Sponges (just for fun)
It can render Lambertian, mirror and refractive surfaces.
As of v 1.0 there is no support for bitmap textures but to give scenes some artistic sense you can use checker board patterns of any colors and use some experimental features that mess around with surface normals.
Added in this version, you can use tiled textures in .ppm format for axis aligned planes.
To use the basic binary included to render some samples just run from the project directory:
mkdir build
cd build
cmake ..
make
The example binary works as follows:
$ render -h
Usage: render [OPTION]...
If no options are specified, a default Cornell box with 100000 emitted photons and 500 nearest neighbours will be rendered and saved as cornell.ppm.
The resulting images are clamped by default. If they don't look quite right try --noclamp to divide all colors by the maximum or --gamma to use a 2.2 gamma correction.
Available options:
-h : Print this helpful text.
--res <WIDTHxHEIGHT> : Select a different resolution for the result image.
--clamp : Instead of dividing by the greatest color value in the image, all colors will be clamped.
--gamma : Instead of dividing by the greatest color value in the image, all colors will be gamma corrected and then clamped.
-p <INTEGER> : Emits INTEGER photons. The default value is 100,000.
-k <INTEGER> : When tracing rays search for the INTEGER nearest photons. The default value is 300.
-s [SCENE_NAME] : Selects the scene to render.
Available scenes:
caustic
chess_texture
cornell
cornell_media
diamond_sphere
direct_vs_indirect
dragon
experimental
glass_sphere
glass_sphere_2
indirect
infinite_mirror
media_0
media_1
media_caustic
menger_1
menger_2
menger_3
menger_4
menger_5
mirror_caustic
phong_spheres
quartz_sphere
rat_in_glass
room
specular_lobe_1
specular_lobe_2
specular_lobe_3
spheres
teapot
water_sphere
These are some of the results achieved using the example code.
This is the second project of a computer graphics course. As such, it could be used in similar environments. It's unlikely that this project will be mantained or improved in any way but it should remain as a way to satisfy some curious mind out there.
If you're using this repository as a reference for a class project keep in mind not to copy anything directly, teachers know about GitHub 😉.
This project was made by Santiago Gil Begué and Miguel Jorge Galindo Ramos.