2020 – Landscape Archaeology

Combining hillshades: beauty is not all there is to it!

[This is the third post in my series on hillshades: previous ones were on the functionality of QGIS Terrain Shading module and some ramblings on the combination of multiple hillshades.]…

Uncategorized

Cartographier, penser : des cartes du foie à la foi en cartes

Introduction Les cartes, géographiques ou autres, sont une fenêtre remarquable sur l'espace mental de leurs producteurs et utilisateurs. Mais, les cartes sont excessivement rares en archéologie… peut-être parce que nous…

Uncategorized

Pebbles, faces and landscapes: the archaeology of simulacra

Chichibu museum (photo: www.thisiscolossal.com) Several weeks ago I stumbled upon an amusing article on a museum displaying pebbles and rocks resembling human faces, situated in Chichibu, Japan. The stones are…

Uncategorized

Le géosymbole et la sémiotique, vus par l’archéologie

Le concept de géosymbole est issu du mouvement culturaliste en géographie des années 80, suite au désenchantement par les approches structuralistes. Ces dernières semblaient reléguer l’humain en marges du grand…

QGIS plugins

Hillshade in QGIS: how does it work ?

Figure 1. Hillshade model of Požega valley (Croatia). Hillshade modelling is a standard form of terrain representation in cartography. The idea is to simulate light reflectance form a terrain surface,…

QGIS plugins

Visibility index (total viewshed) for QGIS : finally there!

Welcome visibility index algorithm, a.k.a. total viewshed, now available in QGIS Visibility analysis plugin. This metric informs us on the size of the visual field for any location across a…

Uncategorized

Name the enemy: geographic projections in GIS

So, you have your data, you’ve installed a GIS program … and there we go: slope gradient – check, solar exposition – check, water drainage – check, visibility range –…

QGIS plugins

Distance and direction filters for QGIS Viewshed analysis

Viewshed analysis produces a model of visible areas from a chosen point, given a 2.5 or 3D elevation model. Most often, we model full range visibility, in all directions from…

QGIS plugins

Viewshed analysis in QGIS 3: a tutorial

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…

QGIS plugins

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…