Inferred Lighting

Lecture by Scott Kircher and Alan Lawrence at SIGGRAPH 2009.

This paper presents a three phase pipeline for real-time rendering that provides fast dynamic light calculations while enabling greater material flexibility than deferred shading. This method, called inferred lighting, allows lighting calculations to occur at a significantly lower resolution than the final output and is compatible with hardware multisample antialiasing (MSAA). In addition, inferred lighting introduces a novel method of computing lighting and shadows for translucent objects (alpha polygons) that unifies the pipeline for processing lit alpha polygons with that of opaque polygons. The key to our method is a discontinuity sensitive filtering algorithm that enables material shaders to “infer” their lighting values from a light buffer sampled at a different resolution. This paper also discusses specific implementation issues of inferred lighting on DirectX 10, Xbox 360, and PlayStation 3 hardware.