https://github.com/raybellis/rrt

Ray's Ray Tracer
https://github.com/raybellis/rrt

Last synced: 3 days ago
JSON representation

Ray's Ray Tracer

• Host: GitHub
• URL: https://github.com/raybellis/rrt
• Owner: raybellis
• License: gpl-3.0
• Created: 2015-02-03T07:41:03.000Z (almost 10 years ago)
• Default Branch: master
• Last Pushed: 2017-04-17T13:09:30.000Z (over 7 years ago)
• Last Synced: 2024-12-06T21:42:26.825Z (20 days ago)
• Language: C++
• Homepage: http://raybellis.github.io/RRT
• Size: 1.35 MB
• Stars: 0
• Watchers: 3
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

Awesome Lists containing this project

README

        
# RRT - Ray's Ray Tracer

RRT is a _stochastic_, _multithreaded_ ray tracer written in C++ that relies on casting a very high number of samples per pixel into the scene and then scatters diffuse rays in every direction.

The method is far from efficient and producing a noise-free image may take thousands of samples per pixel (and hours of CPU time) but it produces effects "for free" that many other ray tracers can only approximate, including:

- diffuse inter-reflection (colour bleeding)

- area lighting and soft shadow

- glossy surfaces

- depth-of-field

- caustics

The current implementation supports a limited number of 3D primitives:

- spheres (of course!)

- cubes

- infinite planes

- triangle

- triangle meshes (via Open Asset Import Library)

- compound (parent node for collections of the above)

Arbitrary homogenous transformations are supported to move and deform primitives, but as yet these transformations cannot be nested.  That is to say, a compound node cannot yet have a transformation that applies to all child nodes within it.

There is no scene description language - the user has to write a C++ program that makes call to the RRT APIs that create nodes, attach shaders to nodes, etc.   See the example programs in `scenes/` for more details.

The most powerful shader is `Shader::stochastic` that can take a `surface` object that is similar to those used in other ray tracers and will automatically cast a single diffuse ray, a specular reflected ray and a tranmitted ray, depending on the surface's properties.

For a surface that has purely diffuse lighting properties the `Shader::diffuse` shader can be used instead and is slightly more efficient than `Shader::stochastic` because it doesn't have to consider the surface properties to decide whether to cast any non-diffuse rays.

There are no "lights" in RRT.  Any object can have a `Shader::constant` shader attached to it that makes that object a fixed colour and indirectly causes it to "illuminate" any object that casts a ray in its direction.

## Compiling

RRT requires a C++11 compatible compiler, Boost, Open Asset Import Library, GD, libpng, libjpeg and libz.  The supplied Makefile is for Mac OS X with macports.

## Running

Two samples scenes are included so far, "snooker" and "cornell".

The demo programs will either start a new render, or if passed a `.rrt` file as parameter will use that as the starting render buffer state.  Every eight samples the current render buffer is rewritten to the `.rrt` file, as well as a 48-bpp PPM file.   The `netpbm` package can be used to convert  PPM files into PNG or JPEG, or many other formats.

## TODO

- More primitives

- Bounding volume / Spatial acceleration techniques

- Compound transformations

- Time-based transformations (motion blur!)

- ~~Ensure partial frames can't end up in the `.rrt` files~~