EcoBrush: Interactive Control of Visually Consistent Large‐Scale Ecosystems

• Published in: Computer graphics forum Vol. 36; no. 2; pp. 63 - 73
• Main Authors: Gain, J., Long, H., Cordonnier, G., Cani, M.‐P.
• Format: Journal Article
• Language: English
• Published: Oxford Blackwell Publishing Ltd 01.05.2017; Wiley
• Subjects: 1.3.7 [Computer Graphics]: Three‐dimensional graphics and realism; Brushes; Categories and Subject Descriptors (according to ACM CCS); Computer graphics; Computer Science; Computer simulation; Ecosystems; Flowers & plants; Graphics; Interactive control; Plants (botany); Rainfall; Simulation; Terrain; Virtual environments; Virtual reality
• ISSN: 0167-7055; 1467-8659; 1467-8659
• DOI: 10.1111/cgf.13107

One challenge in portraying large‐scale natural scenes in virtual environments is specifying the attributes of plants, such as species, size and placement, in a way that respects the features of natural ecosystems, while remaining computationally tractable and allowing user design. To address this, we combine ecosystem simulation with a distribution analysis of the resulting plant attributes to create biome‐specific databases, indexed by terrain conditions, such as temperature, rainfall, sunlight and slope. For a specific terrain, interpolated entries are drawn from this database and used to interactively synthesize a full ecosystem, while retaining the fidelity of the original simulations. A painting interface supplies users with semantic brushes for locally adjusting ecosystem age, plant density and variability, as well as optionally picking from a palette of precomputed distributions. Since these brushes are keyed to the underlying terrain properties a balance between user control and real‐world consistency is maintained. Our system can be be used to interactively design ecosystems up to 5 × 5 km2 in extent, or to automatically generate even larger ecosystems in a fraction of the time of a full simulation, while demonstrating known properties from plant ecology such as succession, self‐thinning, and underbrush, across a variety of biomes.