DGtal::functors::Point2ShapePredicate< TSurface, isUpward, isClosed > Class Template Reference

#include <DGtal/shapes/fromPoints/Point2ShapePredicate.h>

Public Types
typedef TSurface::Point	Point
typedef TSurface::Distance	Distance

Public Member Functions
	Point2ShapePredicate (const TSurface &aSurface)
	Point2ShapePredicate (const Point2ShapePredicate &other)
bool	operator() (const Point &p) const
void	selfDisplay (std::ostream &out) const
	~Point2ShapePredicate ()

Private Attributes
TSurface	myS

Detailed Description

template<typename TSurface, bool isUpward, bool isClosed>
class DGtal::functors::Point2ShapePredicate< TSurface, isUpward, isClosed >

Aim: Predicate returning 'true' iff a given point is in the 'interior' of a given shape, 'false' otherwise.

Template Parameters

TSurface	a type that is a model of COrientableHypersurface. Must separate the space in two disjoints parts (the 'interior' and the 'exterior') and must be able to return for any given point (of type TSurface::Point) the signed distance to itself (of type TSurface::Distance) by a method called signedDistance()
isUpward	a bool for the orientation ('true' means that the interior is the set of points of positive distance)
isClosed	a bool for the closure ('true' means that the surface is included)

For instance, in 2d, you can define four shapes from one straight line of equation \( y = ax + b \):

• the set \( \{(x,y) | y > ax + b \} \)
  - \( \{(x,y) | y \geq ax + b \} \)
• \( \{(x,y) | y < ax + b \} \)

• \( \{(x,y) | y \leq ax + b \} \)

  The second set can be defined as follows:

    typedef Point2ShapePredicate<StraightLine,true,true> UpClosedHalfPlane;

  Then, you can create and use your half-plane as shown below:

    //line is an instance of StraightLine
    UpClosedHalfPlane hp(line);
    trace.info() << hp << std::endl;
    trace.info() << "Does " << r1 << " belongs to hp (no)?" << std::endl;
    res = hp(r1)?"yes":"no";
    trace.info() << res << std::endl;

  You should get:

    [Point2ShapePredicate] :
  [StraightLine] passing through:
  [PointVector] {0, 0}[PointVector] {5, 2}
  (upward oriented, closed)
  
    Does [PointVector] {2, 0} belongs to hp (no)?
    no

  This class is a model of concepts::CPointPredicate.

  See also

  testHalfPlane.cpp

Definition at line 95 of file Point2ShapePredicate.h.

Member Typedef Documentation

Distance

template<typename TSurface, bool isUpward, bool isClosed>

typedef TSurface::Distance DGtal::functors::Point2ShapePredicate< TSurface, isUpward, isClosed >::Distance

Definition at line 101 of file Point2ShapePredicate.h.

Point

template<typename TSurface, bool isUpward, bool isClosed>

typedef TSurface::Point DGtal::functors::Point2ShapePredicate< TSurface, isUpward, isClosed >::Point

Definition at line 100 of file Point2ShapePredicate.h.

Constructor & Destructor Documentation

Point2ShapePredicate() [1/2]

template<typename TSurface, bool isUpward, bool isClosed>

DGtal::functors::Point2ShapePredicate< TSurface, isUpward, isClosed >::Point2ShapePredicate

(

const TSurface &

aSurface

)

Constructor.

Parameters

aSurface

any Surface

Point2ShapePredicate() [2/2]

template<typename TSurface, bool isUpward, bool isClosed>

DGtal::functors::Point2ShapePredicate< TSurface, isUpward, isClosed >::Point2ShapePredicate

(

const Point2ShapePredicate< TSurface, isUpward, isClosed > &

other

)

Copy constructor.

Parameters

other

the object to clone.

~Point2ShapePredicate()

template<typename TSurface, bool isUpward, bool isClosed>

DGtal::functors::Point2ShapePredicate< TSurface, isUpward, isClosed >::~Point2ShapePredicate

(

)

Destructor. Does nothing

Member Function Documentation

operator()()

template<typename TSurface, bool isUpward, bool isClosed>

bool DGtal::functors::Point2ShapePredicate< TSurface, isUpward, isClosed >::operator()

(

const Point &

p

)

const

Parameters

p	any point.

Returns

true iff p is in the interior of the shape.

selfDisplay()

template<typename TSurface, bool isUpward, bool isClosed>

void DGtal::functors::Point2ShapePredicate< TSurface, isUpward, isClosed >::selfDisplay

(

std::ostream &

out

)

const

Writes/Displays the object on an output stream.

Parameters

out	the output stream where the object is written.

Field Documentation

myS

template<typename TSurface, bool isUpward, bool isClosed>

TSurface DGtal::functors::Point2ShapePredicate< TSurface, isUpward, isClosed >::myS

private

The surface with respect to the points have to be located

Definition at line 141 of file Point2ShapePredicate.h.

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

• Point2ShapePredicate.h