Terrain modeling by example

Adding detail to terrains by hand or with paint tools is a long and tedious process. Adding detail with procedural methods is faster but makes it difficult to produce desired features. This work introduces a new technique of terrain synthesis that uses an existing terrain to help synthesize new terrain. To do this we extract the fine, high-resolution details from existing models and we use them to increase the realism of a synthesized terrain. Multiresolution analysis is used to extract and apply these fine details. We also explore applying the details with a multi-fractal based approach. We then describe both an automatic and an interactive method for describing the relationship between the synthesized and existing terrain. To assist in contrasting between terrains we use two coloring schemes and non-photorealistic rendering in addition to Gouraud shading. The terrains produced by our system are synthesized quickly, reflect the nature of the example terrain, are much more heterogeneous than procedural terrains, are superior to terrains created by texture transfer techniques, and retain the large-scale characteristics of the original terrain.