Geom2dAPI_ExtremaCurveCurve Class Reference

Describes functions for computing all the extrema between two 2D curves. An ExtremaCurveCurve algorithm minimizes or maximizes the distance between a point on the first curve and a point on the second curve. Thus, it computes the start point and end point of perpendiculars common to the two curves (an intersection point is not an extremum except where the two curves are tangential at this point). Solutions consist of pairs of points, and an extremum is considered to be a segment joining the two points of a solution. An ExtremaCurveCurve object provides a framework for: More...

`#include <Geom2dAPI_ExtremaCurveCurve.hxx>`

## Public Member Functions

Geom2dAPI_ExtremaCurveCurve (const Handle< Geom2d_Curve > &C1, const Handle< Geom2d_Curve > &C2, const Quantity_Parameter U1min, const Quantity_Parameter U1max, const Quantity_Parameter U2min, const Quantity_Parameter U2max)
Computes the extrema between. More...

Standard_Integer NbExtrema () const
Returns the number of extrema computed by this algorithm. Note: if this algorithm fails, NbExtrema returns 0. More...

operator Standard_Integer () const

void Points (const Standard_Integer Index, gp_Pnt2d &P1, gp_Pnt2d &P2) const
Returns the points P1 on the first curve and P2 on the second curve, which are the ends of the extremum of index Index computed by this algorithm. Exceptions Standard_OutOfRange if Index is not in the range [ 1,NbExtrema ], where NbExtrema is the number of extrema computed by this algorithm. More...

void Parameters (const Standard_Integer Index, Quantity_Parameter &U1, Quantity_Parameter &U2) const
Returns the parameters U1 of the point on the first curve and U2 of the point on the second curve, which are the ends of the extremum of index Index computed by this algorithm. Exceptions Standard_OutOfRange if Index is not in the range [ 1,NbExtrema ], where NbExtrema is the number of extrema computed by this algorithm. More...

Quantity_Length Distance (const Standard_Integer Index) const
Computes the distance between the end points of the extremum of index Index computed by this algorithm. Exceptions Standard_OutOfRange if Index is not in the range [ 1,NbExtrema ], where NbExtrema is the number of extrema computed by this algorithm. More...

void NearestPoints (gp_Pnt2d &P1, gp_Pnt2d &P2) const
Returns the points P1 on the first curve and P2 on the second curve, which are the ends of the shortest extremum computed by this algorithm. Exceptions StdFail_NotDone if this algorithm fails. More...

void LowerDistanceParameters (Quantity_Parameter &U1, Quantity_Parameter &U2) const
Returns the parameters U1 of the point on the first curve and U2 of the point on the second curve, which are the ends of the shortest extremum computed by this algorithm. Exceptions StdFail_NotDone if this algorithm fails. More...

Quantity_Length LowerDistance () const
Computes the distance between the end points of the shortest extremum computed by this algorithm. Exceptions - StdFail_NotDone if this algorithm fails. More...

operator Standard_Real () const

const Extrema_ExtCC2dExtrema () const

## Detailed Description

Describes functions for computing all the extrema between two 2D curves. An ExtremaCurveCurve algorithm minimizes or maximizes the distance between a point on the first curve and a point on the second curve. Thus, it computes the start point and end point of perpendiculars common to the two curves (an intersection point is not an extremum except where the two curves are tangential at this point). Solutions consist of pairs of points, and an extremum is considered to be a segment joining the two points of a solution. An ExtremaCurveCurve object provides a framework for:

• defining the construction of the extrema,
• implementing the construction algorithm, and
• consulting the results. Warning In some cases, the nearest points between two curves do not correspond to one of the computed extrema. Instead, they may be given by:
• a limit point of one curve and one of the following:
• its orthogonal projection on the other curve,
• a limit point of the other curve; or
• an intersection point between the two curves.

## Constructor & Destructor Documentation

 Geom2dAPI_ExtremaCurveCurve::Geom2dAPI_ExtremaCurveCurve ( const Handle< Geom2d_Curve > & C1, const Handle< Geom2d_Curve > & C2, const Quantity_Parameter U1min, const Quantity_Parameter U1max, const Quantity_Parameter U2min, const Quantity_Parameter U2max )

Computes the extrema between.

• the portion of the curve C1 limited by the two points of parameter (U1min,U1max), and
• the portion of the curve C2 limited by the two points of parameter (U2min,U2max). Warning Use the function NbExtrema to obtain the number of solutions. If this algorithm fails, NbExtrema returns 0.

## Member Function Documentation

 Quantity_Length Geom2dAPI_ExtremaCurveCurve::Distance ( const Standard_Integer Index ) const

Computes the distance between the end points of the extremum of index Index computed by this algorithm. Exceptions Standard_OutOfRange if Index is not in the range [ 1,NbExtrema ], where NbExtrema is the number of extrema computed by this algorithm.

 const Extrema_ExtCC2d& Geom2dAPI_ExtremaCurveCurve::Extrema ( ) const
 Quantity_Length Geom2dAPI_ExtremaCurveCurve::LowerDistance ( ) const

Computes the distance between the end points of the shortest extremum computed by this algorithm. Exceptions - StdFail_NotDone if this algorithm fails.

 void Geom2dAPI_ExtremaCurveCurve::LowerDistanceParameters ( Quantity_Parameter & U1, Quantity_Parameter & U2 ) const

Returns the parameters U1 of the point on the first curve and U2 of the point on the second curve, which are the ends of the shortest extremum computed by this algorithm. Exceptions StdFail_NotDone if this algorithm fails.

 Standard_Integer Geom2dAPI_ExtremaCurveCurve::NbExtrema ( ) const

Returns the number of extrema computed by this algorithm. Note: if this algorithm fails, NbExtrema returns 0.

 void Geom2dAPI_ExtremaCurveCurve::NearestPoints ( gp_Pnt2d & P1, gp_Pnt2d & P2 ) const

Returns the points P1 on the first curve and P2 on the second curve, which are the ends of the shortest extremum computed by this algorithm. Exceptions StdFail_NotDone if this algorithm fails.

 Geom2dAPI_ExtremaCurveCurve::operator Standard_Integer ( ) const
 Geom2dAPI_ExtremaCurveCurve::operator Standard_Real ( ) const
 void Geom2dAPI_ExtremaCurveCurve::Parameters ( const Standard_Integer Index, Quantity_Parameter & U1, Quantity_Parameter & U2 ) const

Returns the parameters U1 of the point on the first curve and U2 of the point on the second curve, which are the ends of the extremum of index Index computed by this algorithm. Exceptions Standard_OutOfRange if Index is not in the range [ 1,NbExtrema ], where NbExtrema is the number of extrema computed by this algorithm.

 void Geom2dAPI_ExtremaCurveCurve::Points ( const Standard_Integer Index, gp_Pnt2d & P1, gp_Pnt2d & P2 ) const

Returns the points P1 on the first curve and P2 on the second curve, which are the ends of the extremum of index Index computed by this algorithm. Exceptions Standard_OutOfRange if Index is not in the range [ 1,NbExtrema ], where NbExtrema is the number of extrema computed by this algorithm.

The documentation for this class was generated from the following file: