Efficient modeling of entangled details for natural scenes

• Published in: Computer graphics forum Vol. 35; no. 7; pp. 257 - 267
• Main Authors: Guérin, Eric, Galin, Eric, Grosbellet, François, Peytavie, Adrien, Génevaux, Jean-David
• Format: Journal Article
• Language: English
• Published: Oxford Blackwell Publishing Ltd 01.10.2016; Wiley
• Subjects: Analysis; Approximation; Categories and Subject Descriptors (according to ACM CCS); Computer graphics; Computer Science; Density; Digital; Digital imaging; Ghosts; Graphics; I.3.3 [Computer Graphics]: Picture/Image Generation; I.3.5 [Computer Graphics]: Computational Geometry and Object Modeling-Curve; I.3.5 [Computer Graphics]: Computational Geometry and Object Modeling—Curve, surface, solid and object representations; I.3.7 [Computer Graphics]: Three-Dimensional Graphics and Realism; Landscapes; Nature; Piles; Replication; solid and object representations; Stores; Studies; surface; Computer graphics
• ISSN: 0167-7055; 1467-8659
• DOI: 10.1111/cgf.13023

Digital landscape realism often comes from the multitude of details that are hard to model such as fallen leaves, rock piles or entangled fallen branches. In this article, we present a method for augmenting natural scenes with a huge amount of details such as grass tufts, stones, leaves or twigs. Our approach takes advantage of the observation that those details can be approximated by replications of a few similar objects and therefore relies on mass‐instancing. We propose an original structure, the Ghost Tile, that stores a huge number of overlapping candidate objects in a tile, along with a pre‐computed collision graph. Details are created by traversing the scene with the Ghost Tile and generating instances according to user‐defined density fields that allow to sculpt layers and piles of entangled objects while providing control over their density and distribution.