Grid Concept for Plane Graph Copies ( PlaneGraphCopyGridConcept )

Definition

The class PlaneGraphCopyGridConcept represents an implementation concept for grid layout algorithms which work on a planar map and access the grid layout via an object of type GridLayout. The graph is stored as a plane graph copy PG, which can be modified by the algorithm. The following transformations are performed by the update functions:

• If the polyline of an edge e is empty and the polyline of its reversal is not empty, the reversed polyline of the reversal edge is chosen as polyline for e. Thus, it is sufficient to assign a polyline to an edge or its reversal, no matter which one corresponds to an edge in the original graph.
• The polylines of splitted edges are concatenated.
• Unnecessary bend points are removed.

A computed bounding box can be passed to the grid concept using set_bbox(). Otherwise, the bounding box is computed on demand.

#include < AGD/PlaneGraphCopyGridConcept.h >

Operations

PlaneGraphCopyGridConcept implements the constructors and operations which are required for template argument GRID_CONCEPT of GridLayoutModuleImpl. Furthermore, the following operations are provided:

PlaneGraphCopy&	C.get_graph()	returns the plane graph copy PG.
leda_face	C.get_exterior_face()	returns the exterior face of PG or nil.
GridLayout&	C.get_layout()	returns the grid layout of G.
void	C.set_zero_size()	sets the grid width and height of all nodes to 0.
void	C.set_bbox(const IRect& bbox)
		sets the bounding box of the grid layout to bbox.