Real-time Rendering of Stack-based Terrains

Abstract

Usually, terrain rendering relies on a 2D regular grid of height values, the so called height field. Height fields describe 2.5D surfaces and are not able to present complex 3D terrain features. In contrast, a 3D data representation quickly exceeds the available memory resources. To overcome this problem we apply material stacks. Material stacks combine the simplicity of 2D height fields and the extended modeling capabilities of 3D volumetric data. However, this approach requires expensive rendering and is difficult to realize in real-time. In this paper we present an innovative real-time rendering approach of terrains relying on material stacks. Our approach is based on two major steps: First, a LoD hierarchy for material-stacks is generated. Second, during rendering a multi-staged quadrangulation pipeline extracts terrain surface from the material stacks. As a result, we achieve real-time frame rates at high resolutions.