Terrain Modelling from Feature Primitives

• Published in: Computer graphics forum Vol. 34; no. 6; pp. 211 - 227
• Main Authors: Génevaux, Jean-David, Galin, Eric, Peytavie, Adrien, Guérin, Eric, Briquet, Cyril, Grosbellet, François, Benes, Bedrich
• Format: Journal Article
• Language: English
• Published: Oxford Blackwell Publishing Ltd 01.09.2015; Wiley
• Subjects: Analysis; and object representations; Computer Science; Elevation; geometric modelling; Graphics; I.3.5 Computational Geometry and Object Modeling Surface; I.3.5 Computational Geometry and Object Modeling Surface, and object representations; I.3.6 Methodology and Techniques Graphics data structures, Interaction techniques; I.3.6 Methodology and Techniques Graphics data structures; Image processing systems; Interaction techniques; Land; Landscape ecology; Leaves; Mathematical analysis; Mathematical models; Modeling and Simulation; Mountains; natural phenomena; Operators; procedural modelling; Studies; Terrain; terrain modelling; Topological manifolds; Trees; natural phenomena; procedural modeling; terrain modeling; geometric modelling
• ISSN: 0167-7055; 1467-8659
• DOI: 10.1111/cgf.12530

We introduce a compact hierarchical procedural model that combines feature‐based primitives to describe complex terrains with varying level of detail. Our model is inspired by skeletal implicit surfaces and defines the terrain elevation function by using a construction tree. Leaves represent terrain features and they are generic parametrized skeletal primitives, such as mountains, ridges, valleys, rivers, lakes or roads. Inner nodes combine the leaves and subtrees by carving, blending or warping operators. The elevation of the terrain at a given point is evaluated by traversing the tree and by combining the contributions of the primitives. The definition of the tree leaves and operators guarantees that the resulting elevation function is Lipschitz, which speeds up the sphere tracing used to render the terrain. Our model is compact and allows for the creation of large terrains with a high level o detail using a reduced set of primitives. We show the creation of different kinds of landscapes and demonstrate that our model allows to efficiently control the shape and distribution of landform features. We introduce a compact hierarchical procedural model that combines feature‐based primitives to describe complex terrains with varying level of detail. Our model is inspired by skeletal implicit surfaces and defines the terrain elevation function by using a construction tree. Leaves represent terrain features and they are generic parametrized skeletal primitives, such as mountains, ridges, valleys, rivers, lakes or roads. Inner nodes combine the leaves and subtrees by carving, blending or warping operators. The elevation of the terrain at a given point is evaluated by traversing the tree and by combining the contributions of the primitives. The definition of the tree leaves and operators guarantees that the resulting elevation function is Lipschitz, which speeds up the sphere tracing used to render the terrain. Our model is compact and allows for the creation of large terrains with a high level o detail using a reduced set of primitives.