Real-Time Volumetric Tests Using Layered Depth Images

Abstract

This paper presents a new approach for performing efficiently 3D point-in-volume tests for solid and arbitrary complex shapes. It classifies a 3D point as inside or outside of a solid specified by 3D polygonal geometry. Our technique implements a basic functionality that offers a wide range of applications such as clipping, collision detection, interactive rendering of multiple 3D lenses as well as rendering using multiple styles. It is based on an extension of layered depth images (LDI) in combination with shader programs. An LDI contains layers of unique depth complexity and is represented by a 3D volume texture. The test algorithm transforms a 3D point into an LDI texture space and, then, performs ray marching through the depth layers to determine its classification. We show how to apply real-time volumetric tests to implement 3D clipping and rendering using multiple styles. In addition, we discuss limitations and possible improvements.