High-quality shadows with improved paraboloid mapping

Abstract

This paper introduces a novel approach in the rendering of high-quality shadows in real-time. The contemporary approach to shadow rendering in real-time is shadow maps algorithm. The standard shadow maps suffer from discretization and aliasing due to the limited resolution of the shadow texture. Moreover, omnidirectional lights need additional treatment to work correctly (e.g. with dual-paraboloid shadow maps). We propose a new technique that significantly reduces the aliasing problem and works correctly for various kinds of light sources. Our technique adapts the light's field-of-view to the visible part of the scene and thus stores only the relevant part of the scene to the full resolution of the shadow map. It produces high-quality shadows which are not constrained by position or type of the light sources and also works in fully dynamic scenes. This paper describes the new approach, presents some results, and discusses the potential, features and future of the approach. © 2011 Springer-Verlag.