Shape-Guided Mixed Metro Map Layout

TL;DR

This paper introduces a systematic approach to generate shape-guided mixed metro maps, combining symbolic shape embedding with classical layout conventions, to improve visual guidance and reduce manual effort.

Contribution

It formulates the mixed metro map design problem with optimization criteria and presents a three-step algorithm for automated map generation with user-defined shapes.

Findings

The approach effectively embeds recognizable shapes into metro maps.

User study shows shapes are identifiable without compromising map clarity.

The method reduces manual effort in creating shape-guided transit maps.

Abstract

Metro or transit maps, are schematic representations of transit networks to facilitate effective route-finding. These maps are often advertised on a web page or pamphlet highlighting routes from source to destination stations. To visually support such route-finding, designers often distort the layout by embedding symbolic shapes (e.g., circular routes) in order to guide readers' attention (e.g., Moscow map and Japan railway map). However, manually producing such maps is labor-intensive and the effect of shapes remains unclear. In this paper, we propose an approach to generalize such mixed metro maps that take user-defined shapes as an input. In this mixed design, lines that are used to approximate the shapes are arranged symbolically, while the remaining lines follow classical layout convention. A three-step algorithm, including (1) detecting and selecting routes for shape approximation, (2) shape and layout deformation, and (3) aligning lines on a grid, is integrated to guarantee good visual quality. Our contribution lies in the definition of the mixed metro map problem and the formulation of design criteria so that the problem can be resolved systematically using the optimization paradigm. Finally, we evaluate the performance of our approach and perform a user study to test if the embedded shapes are recognizable or reduce the map quality.