NLPACS::CEdgeCollide Class Reference

Collisions against edge in 2D. More...

#include <edge_collide.h>

Public Types
enum	TPointMoveProblem { ParallelEdges = 0, StartOnEdge, StopOnEdge, TraverseEndPoint, EdgeNull, PointMoveProblemCount }
Public Member Functions
void	make (const CVector2f &p0, const CVector2f &p1)
CRational64	testPointMove (const CVector2f &start, const CVector2f &end, TPointMoveProblem &moveBug)
	return 1 either if no collision occurs.
float	testCircleMove (const CVector2f &start, const CVector2f &delta, float radius, CVector2f &normal)
	return 1 either if the circle moves away from the line, or no collision occurs.
float	testBBoxMove (const CVector2f &start, const CVector2f &delta, const CVector2f bbox[4], CVector2f &normal)
	return 1 either if the bbox moves away from the line, or no collision occurs.
bool	testBBoxCollide (const CVector2f bbox[4])
	return true if this oriented bbox collide this edge.
Public Attributes
CVector2f	P0
CVector2f	P1
CVector2f	Dir
CVector2f	Norm
float	A0
float	A1
float	C
Private Member Functions
bool	testEdgeMove (const CVector2f &q0, const CVector2f &q1, const CVector2f &delta, float &tMin, float &tMax, bool &normalOnBox)
	test if edge collide against me.

Detailed Description

Collisions against edge in 2D.

Author:: Lionel Berenguier; Nevrax France

Date:: 2001

Definition at line 178 of file edge_collide.h.

Member Enumeration Documentation

enum NLPACS::CEdgeCollide::TPointMoveProblem

Enumerator:

ParallelEdges
StartOnEdge
StopOnEdge
TraverseEndPoint
EdgeNull
PointMoveProblemCount

Definition at line 181 of file edge_collide.h.

Member Function Documentation

void NLPACS::CEdgeCollide::make	(	const CVector2f &	p0,
		const CVector2f &	p1
	)

Definition at line 41 of file edge_collide.cpp.

References A0, A1, C, Dir, Norm, NLMISC::CVector2f::normalize(), P0, P1, NLMISC::CVector2f::x, and NLMISC::CVector2f::y.

Referenced by NLPACS::CLocalRetriever::testCollision(), and NLPACS::CRetrieverInstance::testExteriorCollision().

bool NLPACS::CEdgeCollide::testBBoxCollide ( const CVector2f bbox[4] )

return true if this oriented bbox collide this edge.

Parameters:

bbox

4 points of the bbox, in CCW.

Returns:: true if collision occurs.

Definition at line 654 of file edge_collide.cpp.

References P0, P1, and NLMISC::CVector2f::x.

Referenced by NLPACS::CGlobalRetriever::testRotCollisionWithCollisionChains().

float NLPACS::CEdgeCollide::testBBoxMove	(	const CVector2f &	start,
		const CVector2f &	delta,
		const CVector2f	bbox[4],
		CVector2f &	normal
	)

return 1 either if the bbox moves away from the line, or no collision occurs.

Else return a [0,1[ interval. If collision occurs (ie return<1), return in "normal" the normal of the collision. It may be normal of edge (+-), or normal against a point of the edge.

Parameters:

bbox

4 points of the bbox at start. start must be the barycentre of those points.

Definition at line 556 of file edge_collide.cpp.

References C, min, Norm, testEdgeMove(), NLMISC::CVector2f::x, and NLMISC::CVector2f::y.

Referenced by NLPACS::CGlobalRetriever::testCollisionWithCollisionChains().

float NLPACS::CEdgeCollide::testCircleMove	(	const CVector2f &	start,
		const CVector2f &	delta,
		float	radius,
		CVector2f &	normal
	)

return 1 either if the circle moves away from the line, or no collision occurs.

Else return a [0,1[ interval. If collision occurs (ie return<1), return in "normal" the normal of the collision. It may be normal of edge (+-), or normal against a point of the edge.

Definition at line 264 of file edge_collide.cpp.

References A0, A1, C, Dir, NLMISC::CVector2f::isNull(), min, Norm, NLMISC::CVector2f::normalize(), P0, P1, and NLPACS::testCirclePoint().

Referenced by NLPACS::CGlobalRetriever::testCollisionWithCollisionChains().

bool NLPACS::CEdgeCollide::testEdgeMove	(	const CVector2f &	q0,
		const CVector2f &	q1,
		const CVector2f &	delta,
		float &	tMin,
		float &	tMax,
		bool &	normalOnBox
	)			`[private]`

test if edge collide against me.

if true, return time intervals of collisions (]-oo, +oo[). NB: for simplicity, if lines are //, return false.

Definition at line 391 of file edge_collide.cpp.

References NLPACS::EdgeCollideEpsilon, min, NLMISC::CVector2f::norm(), P0, P1, NLMISC::CVector2d::sqrnorm(), NLMISC::CVector2d::x, and NLMISC::CVector2d::y.

Referenced by testBBoxMove().

CRational64 NLPACS::CEdgeCollide::testPointMove	(	const CVector2f &	start,
		const CVector2f &	end,
		TPointMoveProblem &	moveBug
	)

return 1 either if no collision occurs.

Else return a [0,1[ interval. return -1 if precision problem (see below). This method is used by CGlobalRetriever::doMove(). UnManageables cases arise when:

the movement start/stop on a edge (dist==0). In this case, don't know on what surface we arrive (before or after).
the movement is // to the edge and collide with it. same problem than stop on an edge.
the movement traverse the edge on an endpoint. In this case, there is 2+ edges sharing the point, and result is undefined. On thoses cases, moveBug is filled, and -1 is returned.

Definition at line 58 of file edge_collide.cpp.

References EdgeNull, NLMISC::fsgn(), nlassert, P0, P1, ParallelEdges, StartOnEdge, StopOnEdge, TraverseEndPoint, NLMISC::CVector2f::x, and NLMISC::CVector2f::y.