Efficient Multiscale Representations for Geographical Objects

Abstract

Maps need different representations of the same cartographic object in order to display it at several scale levels. When a user zooms in, the object should depict every detail as it is the main focus on the map. On the contrary, when the user zooms out, there is no need to display every single detail of the object as most would become as small as to be invisible. A common technique to speed up the display process is storing several representations for the same object at different scales. However, this technique raises redundancy, and therefore it increases space usage. This work aims at suppressing that redundancy by introducing four alternatives that use a unique representation for each cartographic object while still being able to retrieve simplified versions of them depending on the requested scale.

This work was supported by the CITIC research center funded by Xunta/FEDER-UE 2014–2020 Program grant ED431G 2019/01. Partially funded by MCIU-AEI/ FEDER-UE [BIZDEVOPS: RTI2018-098309-B-C32]; by MICINN (PGE/ERDF) [EXTRA-Compact: PID2020-114635RB-I00; MAGIST: PID2019-105221RB-C41; SIGTRANS-UDC: PDC2021-120917-C21; FLATCITY-POC: PDC2021-121239-C31]; by Xunta de Galicia/FEDER-UE [GRC: ED431C 2021/53].