Wu, Maruyama, Kawagoe, Misue, Arikawa and Takahashi – ASPECT-RATIO-PRESERVED LABELING ON METRO MAPS 2019

Description

The paper addresses automated placement of station name labels on octilinear schematic metro maps, where dense downtown regions make labeling difficult without distorting the map’s mental image. Building on prior progressive annotation that orders stations by the sum of geodesic distances (annotating from crowded centers outward) and elongates segments without changing direction, the authors introduce new constraints that preserve the aspect ratios of closed regions (faces) bounded by the network. They embed these constraints in a mixed-integer programming framework that first schematizes the network by minimizing bends, relative positions, and edge lengths, then places labels progressively while enforcing aspect-ratio bounds with a tolerance parameter E to control allowable distortion. Implementation and tests on the Vienna map show that aspect-ratio constraints substantially reduce central-area deformation; a small user study and runtime data are reported. Future work includes better selection of feature regions to further maintain the original mental map.