Real-time image-based lighting without pre-computation

High-fidelity real-time visualization of surfaces under high-dynamic-range (HDR) image-based illumination provides an invaluable resource for various computer graphics applications. Material design, lighting design, architectural previsualization, and gaming are just a few such applications.
We present filtered importance sampling, a technique for image-based lighting of glossy objects using BRDF importance sampling in conjunction with environment map filtering. Furthermore, we extend the algorithm with real-time shadow computation. Free from any pre-computation, the algorithm supports fully dynamic scenes and, above all, is simple to implement.