Luminosity is a simple and elegant ray tracer written in Haskell.

Before compiling, get Luminosity's dependencies.

cabal install json --ghc-options=-DMAP_AS_DICT
cabal install blaze-builder

If you already have JSON, make sure to --reinstall with the MAP_AS_DICT option, otherwise Luminosity won't compile.

Use the build.sh script. This will produce a build folder and a luminosity executable.

• -t: Compile with -threaded for parallelism
• -p: Compile with profiling enabled
• -w: Compile with -Wall (warnings)

If you want to compile yourself, take a look at the end of build.sh to see the command it uses.

To render a scene, run the luminosity executable:

./luminosity Scene.json Image.tga

You can leave out the file extensions if you want. You can also leave out the second argument—in this case, the image would then be written to Scene.tga.

Rather than introducing some custom format, Luminosity uses JSON to describe a scene. JSON is easy to read and there are many existing validation tools.

To learn how to write scenes for Luminosity, check out the Sample scene and the Parse module.

Of special note, all colours and vectors are specified as 3-element arrays. Colour channels are floating-point (0.0–1.0, not 0–255). The width (and aspect ratio) of the camera is dependant on the resolution in the settings, while the height remains constant. Use ortho-scale to increase the size of an orthographic camera, and for perspective cameras, simply move it further back or adjust the focal-length.

For now, the image output format is TGA (Targa) for its simplicity. Soon, it will be PNG instead.

If you are rendering many images, I recommend using a tool such as ImageMagick's convert to convert them to PNG. This will save a lot of space, as the TGA files are not compressed.

• JSON scene input
• TGA image output
• sRGB conversion
• Orthographic and perspective projections
• Sphere and plane primitives
• Lambert diffuse reflection
• Ray traced reflection

• PNG image output
• Parallel rendering
• Faster rendering (optimized Vector)
• Anti-aliasing (supersampling)
• Exposure operator (rather than saturation)
• Blinn–Phong reflection
• Transparency and refraction
• Fresnel effect
• More Surfaces (Cubes, Cones, Cylinders, Metaballs)
• Directional light sources
• Depth of field
• Procedural and bitmap textures
• Bump mapping

Anyone is welcome to contribute! Please try to tackle one of the planned features listed above, and name your branch appropriately.

Copyright © 2012 Mitchell Kember.

Luminosity is available under the MIT license, see LICENSE for details.