Core Concepts
This article presents unified algorithms for straight-line and orthogonal drawing of planar maps with faces of degree at most 4, generalizing several classical algorithms based on transversal structures and separating decompositions.
Abstract
The article introduces a family of combinatorial structures called grand-Schnyder (GS) woods, which generalize the concepts of transversal structures and separating decompositions. The authors present:
A unified straight-line drawing algorithm for planar maps with faces of degree at most 4, based on face-counting and increasing functions on bipolar orientations associated to GS woods.
This algorithm generalizes the straight-line drawing algorithms of Fusy (for planar triangulations) and Barrière-Huemer (for simple quadrangulations).
A unified orthogonal drawing algorithm for the duals of planar maps with faces of degree at most 4, also based on face-counting and increasing functions.
This algorithm generalizes the orthogonal drawing algorithms of He (for the duals of planar triangulations) and Bernardi-Fusy (for the duals of simple quadrangulations).
The authors prove the correctness of the algorithms, analyze their time complexity and grid size, and discuss strategies to optimize the grid size.