CGAL 5.5.1 - 2D Arrangements
DCEL Concepts

## Concepts

conceptArrangementDcel
A doubly-connected edge-list (DCEL for short) data-structure. It consists of three containers of records: vertices $$V$$, halfedges $$E$$, and faces $$F$$. It maintains the incidence relation among them. The halfedges are ordered in pairs sometimes referred to as twins, such that each halfedge pair represent an edge. More...

conceptArrangementDcelFace
A face record in a DCEL data structure. A face represents a region, which may have outer and inner boundaries. A boundary conists of a chain of incident halfedges, referred to as a Connected Component of the Boundary (CCB). A face may be unbounded. Otherwise, it has one or more outer CCBs. A face may also be bounded by inner CCBs, and it may contain isolated vertices in its interior. A planar face may have only one outer CCBs and its inner CCBs are refered to as holes. More...

conceptArrangementDcelHalfedge
A halfedge record in a DCEL data structure. Two halfedges with opposite directions always form an edge (a halfedge pair). The halfedges form together chains, defining the boundaries of connected components, such that all halfedges along a chain have the same incident face. Note that the chain the halfedge belongs to may form the outer boundary of a bounded face (an outer CCB) or the boundary of a hole inside a face (an inner CCB). More...

conceptArrangementDcelInnerCcb
A hole record in a Dcel data structure, which stores the face that contains the hole in its interior, along with an iterator for the hole in the holes' container of this face. More...

conceptArrangementDcelIsolatedVertex
An isolated vertex-information record in a DCEL data structure, which stores the face that contains the isolated vertex in its interior, along with an iterator for the isolated vertex in the isolated vertices' container of this face. More...

conceptArrangementDcelOuterCcb
A hole record in a DCEL data structure, which stores the face that contains the hole in its interior, along with an iterator for the hole in the holes' container of this face. More...

conceptArrangementDcelVertex
A vertex record in a DCEL data structure. A vertex is always associated with a point. However, the vertex record only stores a pointer to the associated point, and the actual Point object is stored elsewhere. More...

conceptArrangementDcelWithRebind
The concept ArrangementDcelWithRebind refines the ArrangementDcel concept by adding a policy clone idiom in form of a rebind struct-template. More...