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Java implementation accompanying the the Journal of Geovisualization and Spatial Analysis article "Polyline Morphing for Animated Schematic Maps" https://doi.org/10.1007/s41651-024-00198-w Animated examples can be found at: https://www.geoinfo.uni-bonn.de/morphing

Bubble charts are often used to visualize numerical data associated with 2D data points: for every data point, a disc centered at the point has area that reflects its data value. When data points are geospatial locations, the visualization is a proportional symbol (circle) map. In a dynamic setting, data values change over time and can be shown using animation or small multiples. Bubble charts and proportional symbol maps suffer when overlapping discs obscure each other, making it difficult to estimate their sizes. We present an approach to remove or significantly reduce overlaps by allowing disc displacement while ensuring that each disc covers its location and that the east-west and north-south order of the discs is preserved. Specifically: (i) we minimize the number of overlapping pairs of discs or the sum of the widths of the overlaps, (ii) we minimize the sum of the distances of disc centers to their locations, and (iii) we minimize the sum of the movements of the discs over time. As even a simplified variant of the underlying problem is NP-hard, we propose solutions to several problem variants with efficiently-solvable quadratic-convex programming. We evaluate our approach on real-world data and compare the results to those obtained with a simpler force-directed approach. A functional prototype, as well as all source-code, datasets, and experiments, are available online.

General input/output interfaces for different geo data sources such as ESRI Shapefiles and OSM-XML files.

This repository contains the complete version of the GraphLibrary with all sub-modules.

This module offers methods to in- and export geographic data from various formats.

This module contains the main logic of the graph library such as an implementation of a directed graph and basic algorithms such as Dijkstra's algorithm.

Fork of https://github.com/PanierAvide/BasicOSMParser

This module offers methods for map matching and thus can be used to for example match trajectory data to a road network.

This module offers methods for drawing maps. The gl-viewer is a fork of the IGGGIS viewer.

python script to keep track of worktime

Collection of specific functions for meta analysis.