We present a system allowing real-time image based lighting based on HDR panoramic images. The system performs time-consuming diffuse light calculations in a pre- processing step, which is key to attaining interactivity. The real-time subsystem processes an image based lighting model in software, which would be simple to implement in hardware. Rendering is handled by OpenGL, but could be substituted for another graphics API. Applications for the technique presented are discussed, and includes methods for realistic outdoor lighting. The system architecture is outlined, describing the algorithms used.
