Viewshed analysis denotes field of vision modelling in GIS jargon. The term is quite awkwardly borrowing its suffix from watershed, even if there is nothing being “shed”. Anyway, the term viewshed has become commonplace in GIS terminology and is here to stay.
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Ambient occlusion and sky-view factor for QGIS
Ambient occlusion is a concept developed in 3D modelling and visualisation which is used to evaluate the exposition to the ambient light of each model element. The idea is to simulate the diffuse, scattered light that bounces off various surfaces. Such light may not have an identifiable source, as for...
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Analysing visual impact of high buildings: the Urkulu tower
Introduction A common problem in visibility analysis is to determine the visual impact of a tall building, for instance a skyscraper or a wind turbine. Now, there is a variety of approaches to measure such impact: how tall does the building stand above the horizon, against which background is it...
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Archéologie des parcellaires : quelques réflexions sur l’exemple du Cantal
Le réseau de parcellaire qui recouvre les campagnes agricoles et pastorales est un sujet particulièrement cher aux archéologues du paysage. Les haies, les chemins, les murets et autres structures qui délimitent les champs cultivés et les pâturages ont parfois une persistance temporelle étonnante : le parcellaire de Hvar, en Croatie,...
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DEM shading algorithm for QGIS
Kickstarter campaign for a happier QGIS :)
I’ve been seeing on the net more and more of beautiful maps made in 3D software, Blender mostly. The reason for venturing into 3D: shadows mostly. While we do have hillshading algorithms in most GIS packages, nothing can beat true ambient light for terrain visualisation. Shadows do not only give...
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