Class representing the special graph constructed from two polygons that is used to perform boolean operation on polygons (polygon clipping in current implementation). More...

#include <geotoolbox.h>

Collaboration diagram for oofem::Graph:

Classes
struct	node

Public Member Functions
	Graph ()

	~Graph ()

void	clip (Polygon &result, const Polygon &a, const Polygon &b)

Protected Types
enum	nodeStatus { NS_Vertex, NS_IntersectionVertex, NS_Intersection }

Protected Member Functions
void	insert (node ins, node first, node *last)

node *	createNode (double x, double y, node next, node prev, node nextPoly, node neighbor, nodeStatus st, int entry, int visited, double alpha)
	Create new node struct. More...

node *	next_node (node *p)

node *	prev_node (node *p)

node *	last_node (node *p)

node *	first (node *p)

void	remove (node *n)

double	dist (double x1, double y1, double x2, double y2)

int	testIfIntersect (node p1, node p2, node q1, node q2, double alpha_p, double alpha_q, double xint, double yint)

int	testIfCoincident (node p1, node p2, node q1, node q2, double alpha_1, double alpha_2)

int	testPoint (node *poly, double x, double y) const

bool	belongs (node n, node v1, node *v2)

bool	intersectionExist (node p1, node p2, node q1, node q2)

void	removeIntersectionIfExist (node p1, node p2, node q1, node q2)

int	vertex2IntersectionVertex (node v, node l1, node *l2)

void	testNewIntersectionVertexEdgeCollapse (node v, node l1, node *l2)

bool	testCollapsedEdge (node p1, node p2)

void	merge2vertex (node v1, node v2)

void	printYourself ()

void	clear ()

Protected Attributes
node *	s

node *	c

Detailed Description

Class representing the special graph constructed from two polygons that is used to perform boolean operation on polygons (polygon clipping in current implementation).

In short, the graph contains polygon vertices and intersections of polygon edges. Then graph edges represent the edges between graph nodes (graph edge correspond to polygon edge if this edge has no intersection with other edges of second polygon, or single polygon edge can be represented by two or more graph edges if intersections are present). Each polygon vertex representing intersection contain link to its twin representing the same intersection on second polygon. This allows to perform traversal walk over graph edges and vertices that can represent various boolean operations. This class is a part of geometry toolbox.

Definition at line 191 of file geotoolbox.h.

Member Enumeration Documentation

enum oofem::Graph::nodeStatus

protected

Enumerator
NS_Vertex
NS_IntersectionVertex
NS_Intersection

Definition at line 194 of file geotoolbox.h.

Constructor & Destructor Documentation

oofem::Graph::Graph ( )

inline

Definition at line 211 of file geotoolbox.h.

oofem::Graph::~Graph ( )

Definition at line 224 of file geotoolbox.C.

References oofem::Polygon::clear().

Member Function Documentation

bool oofem::Graph::belongs	(	node *	n,
		node *	v1,
		node *	v2
	)

protected

Definition at line 1415 of file geotoolbox.C.

References oofem::Graph::node::neighbor, and oofem::Graph::node::status.

void oofem::Graph::clear ( )

protected

Definition at line 231 of file geotoolbox.C.

References oofem::Graph::node::next.

void oofem::Graph::clip	(	Polygon &	result,
		const Polygon &	a,
		const Polygon &	b
	)

Graph::node * oofem::Graph::createNode	(	double	x,
		double	y,
		node *	next,
		node *	prev,
		node *	nextPoly,
		node *	neighbor,
		nodeStatus	st,
		int	entry,
		int	visited,
		double	alpha
	)