A zone-based iterative building displacement method through the collective use of Voronoi Tessellation, spatial analysis and multicriteria decision making

Abstract

An iterative displacement method working based on generalisation zones is proposed as a part of contextual building generalisation in topographic map production at medium scales. Displacement is very complicated operation since a compromise ought to be found between several conflicting criteria. Displacement requirement mainly arises from the violation of minimum distances imposed by graphic limits after the enlargement of map objects for target scale. It is also important to maintain positional accuracy within scale limits and to propagate the changes to the related neighbouring objects by preserving spatial configurations as far as possible. In the proposed method, first it is decided where and when to initiate building displacement based on spatial analysis in the generalisation zones created for building clusters in the blocks. Secondly, relevant criteria are defined to control the displacement. Finally displacement candidate and vector are decided by means of Voronoi tessellation, spatial analysis techniques and combined multiple criteria (i.e. displacement controls) in each iteration. The evaluation of the findings demonstrates that this method is largely effective in zone-based displacement of buildings.A zone-based iterative building displacement method through... RESUMO Neste artigo propõe-se um metodo de deslocamento iterativo baseado na generalização de zonas, como parte da generalização contextual de edificações em mapas topograficos de média escala. O deslocamento é uma operação complicada considerando que deve ser encontrada uma relação entre vários critérios conflitantes. A necessidade para o deslocamento origina-se da incapacidade de manter as distâncias mínimas entre os objetos impostas pelos limites gráficos após o aumento dos objetos do mapa para a escala final. Também é importante manter a acurácia posicional para a esacala e propagar as mudanças aos vizinhos dos objetos preservando ao máximo sua configuração espacial. No método proposto, primieramente é decidido onde e quando iniciar o deslocamento dos edificios com base na análise espacial nas zonas generalizadas criadas pelos agrupamentos de edificações nas quadras. Em seguida, um critério relevante consiste em controlar o deslocamento. Finalmente, os candidatos ao delocamento e os vetores são analisados utilizando Voronoi Tesselation, análise espacial e múltiplos critérios combinados em cada iteração. A avaliação demonstrou que este método é efetivo para deslocamento de edificações baseado em zonas. Bol

Geological Map Generalization Driven by Size Constraints

“…If multiple polygons are in conflict, the pairwise displacement algorithm cannot guarantee that the minimum separability constraint is met everywhere, as it is unable to safeguard against possible knock-on effects when, e.g., a polygon is pushed into another, neighboring polygon that would then also need to be displaced. Therefore, conflict zones involving three or more polygons are handled and are achieved by a Voronoi-based displacement approach inspired by algorithms using Voronoi or Voronoi-like cells to control the displacement [42,43]. We devised two algorithms to implement the displacement operator: a simple pairwise displacement algorithm used when only two polygons are in conflict, and a Voronoi-based algorithm for cases involving multiple polygons.…”

Reducing Building Conflicts in Map Generalization with an Improved PSO Algorithm

“…Basaraner [18] used a Voronoi graph to determine building displacement. In this approach, an operational area for displacement is formed by the overlay of the Voronoi area and a building buffering area.…”

An Immune Genetic Algorithm to Buildings Displacement in Cartographic Generalization

“…Moreover, raster data are used to detect conflicts, and displacement vectors are calculated to resolve these conflicts. Basaraner () proposed a building displacement method based on a Voronoi graph. He first used the overlay of a building's Voronoi region and buffer to form the displacement region, then used a multi‐factor evaluation method to determine displacement object.…”