Octilinearized map
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octi renders input graphs in an octilinear fashion using an approximation approach based on iterative shortest-path calculations on a special grid graph. Octilinearization took under 3 seconds for all examples presented here, enabling usage of our method in map editors. All examples have been schematized using a grid size of either 75%, 100% or 125% of the average distance between adjacent stations in the input graph. For pen-diag, a penalty was added to diagonal grid edges. For pen-hor-ver, a penalty was added to horizontal and vertical edges. For near-geo, edge penalties reflect the distance between the grid edge and the original input edge. For approaches A-2+D (approximate approach with distance penalties) and LP-2 (optimal result using linear programming), station nodes of degree 2 were contracted prior to octilinearization, and re-inserted equidistantly onto the final drawing. Maps were rendered using LOOM.