Deformation using Agents for Map Generalization-Application to the Preservation of Relationships between Fields and Objects

Some research in map generalization techniques using the agent paradigm have allowed to progress significantly toward automation. These models allow the computation of discrete transformations of the objects but are not adapted for continuous transformations such as deformations. Our challenge is to allow these models to manage such continuous transformations. As an application, we aim to introduce field data such as the relief in agent-based generalization models. Many relationships exist between fields and objects (especially buildings, roads and rivers). Our concern is to preserve these relationships. We propose to allow the geographic agents to deform a field during the generalization process. To attain this objective, we propose a model: To measure and interpret relationships between fields and objects (this allows to define new constraints), To compute fields deformations under objects stretching, To manage the automatic trigger of these measurements and deformations in the existing agent based generalization models. We propose to model the field as a triangulation, and to explicit some shape preservation constraints on the points, segments, angles and triangles composing the field. When a point is stretched, its displacement propagates to its neighbors using a multi-agent convergence method we have built.