Occluded Light is an exploration of a photorealistic real-time rendering technique for rendering scattered lighting. And how this real-time technique can be used to create abstract imagery. The light scattering effect is not part of the rendering pipeline of the graphics card therefore shaders are used to program a different behavior into the graphics pipeline.
The steps involved in the rendering process include: Rendering the occluded geometry of the scene before the occluding geometry, store the result in a texture. The texture is then sent to the shader where it is sampled multiple times along the vector from the fragment to the light source and the scattering effect is computed.
To make the visuals more dynamic the effect was conveyed into an audio reactive piece using Quartz Composer. The result is an iTunes visualizer.
Download: Occluded Light Visualizer
Unpack the zip file into one of the following folders "~/Library/Compositions" or "/Library/Compositions". Right click on iTunes.app in your Applications folder and click "Get Info". In the window that appears, click "Open in 32-bit mode" at the bottom of the "General" pane.
Involvement: Design and program the visualizer and shaders.
Technologies: OpenGL / GLSL / Quartz Composer