Strategies for pan-scalar map generalisation

Interaction is at the centre of pan-scalar map design (Gruget et al., 2023), as it allows the user to navigate between diverse representations at various scales.However, these maps are not only collections of independent maps but are an interactive system where the user navigates to see more or less detailed information.In this context, map design has to be redefined to fit the current way of using maps.The specific nature of pan-scalar maps has been investigated with two approaches, 1) by analysing the design of existing maps such as Google Maps or the default OpenStreetMap pan-scalar map (Gruget et al., 2023), and 2) with user surveys (Wenclik and Touya, 2023).This leads to some first attempts to improve map design, for instance with additional representations (Dumont et al., 2023).However, there is still a lack of propositions on how to change the map generalisation processes used to control the level of detail and legibility at a particular scale.The purpose of this article is to explore several generalisation strategies for the creation of a pan-scalar map.The goal of generalisation in pan-scalar maps should be to make the maps easier to use and explore.To fit this objective the map generalisation must provide the most adapted level of information at each zoom level.This assumption leads to several guidelines on pan-scalar map generalisation.