Terrain sketching

Abstract

A] [B] [C] Figure 1: Modeling landscapes by Terrain Sketching: [A] the user sketches a silhouette curve, and [B] optionally modifies the shadow and boundary curves. [C] A matching landscape is created by surface deformation with noise propagation. AbstractProcedural methods for terrain synthesis are capable of creating realistic depictions of heightfield terrains with little user intervention. However, users often do wish to intervene in controlling the placement and shape of landforms, but without sacrificing realism. In this paper, we present a sketching interface to procedural terrain generation. This system enables users to draw the silhouette, spine and bounding curves of both extruding (hills and mountains) and embedding landforms (river courses and canyons).Terrain is interactively generated to match the sketched constraints using multiresolution surface deformation. In addition, the wavelet noise characteristics of silhouette strokes are propagated to the surrounding terrain. With terrain sketching users can interactively create or modify landscapes incorporating varied and complex landforms.

A declarative approach to procedural modeling of virtual worlds

“…Using an efficient gpu-based hydraulic erosion algorithm, Stava et al [21] propose an interactive way for users to modify terrain using several types of hydraulic erosion. To provide users with more control over the exact appearance of mountain ranges, Gain et al [22] introduce a sketch-based height-map generation method in which users sketch the silhouette and bounds of a mountain in a 3D interface, and the generator creates a matching mountain using noise propagation. Even more fine-grained control over the shape of mountains is provided by the interactive procedural brushing system introduced by de Carpentier and Bidarra [23].…”

Automatic terrain generation with a sketching tool

“…Sketching has been commonly applied to model general 3D objects, although there have been proposals to model natural elements like plants [1], clouds [38] or terrain [36,10].…”

“…More recently, Gain et al proposed a new sketching application for terrain modeling [10]. In this solution the authors offer the users the possibility to sketch the silhouette of the heights of the mountains and also the area of influence of this silhouette, widening or stretching the mountains.…”

“…Many of them use some previously-made sketch of the terrain, while only a small subset (papers [4,36,35,10]) allows the user to start from scratch and to interactively sketch the terrain while visualizing the result. Nevertheless, these latter applications are still difficult to control using the different parameters and operations available.…”

“…Among the existing terrain applications presented in the qualitative study we have selected two tools: the one presented by Watanabe and Igarashi [36] and the method proposed by Gain et al [10]. We have chosen these two methods as they are the ones which are strictly more oriented toward offering a complete sketching interface for modeling terrain.…”