Real‐Time Rendering and Editing of Vector‐based Terrains

TLDR

The paper proposes a method to populate very large terrains with highly detailed features such as roads, rivers, lakes, and fields. The approach uses vector-based linear and areal feature descriptions with shaders to define appearance, footprint, and associated objects, and employs a view‑dependent quadtree refinement with GPU caching and multi‑level‑of‑detail via adaptive refinement, procedural vector features, and a mipmap pyramid. The method enables interactive editing of features and real‑time exploration of the landscape at any altitude, achieving high performance while maintaining high visual quality.

Abstract

Abstract We present a method to populate very large terrains with very detailed features such as roads, rivers, lakes and fields. These features can be interactively edited, and the landscape can be explored in real time at any altitude from flight view to car view. We use vector descriptions of linear and areal features, with associated shaders to specify their appearance (terrain color and material), their footprint (effect on terrain shape), and their associated objects (bridges, hedges, etc.). In order to encompass both very large terrains and very fine details we rely on a view dependent quadtree refinement scheme. New quads are generated when needed and cached on the GPU. For each quad we produce on the GPU an appearance texture, a footprint texture, and some object meshes, based on the features vector description and their associated shaders. Adaptive refinement, procedural vector features and a mipmap pyramid provide three LOD mechanisms for small, medium and large scale quads. Our results and attached video show high performance with high visual quality.