An implementation of a convex polygon. More...

#include <ConvexPolygon.h>

Inheritance diagram for Mantid::Geometry::ConvexPolygon:

Classes
class	Iterator

Public Types
using	Vertices = std::vector< Kernel::V2D >
	Type of the point list. More...

Public Member Functions
virtual double	area () const
	Compute the area of the polygon using triangulation. More...

virtual const Kernel::V2D &	at (const size_t index) const
	Bounds-checked index access. More...

void	clear ()
	Clears all points. More...

virtual bool	contains (const ConvexPolygon &poly) const
	Is a the given polygon completely encosed by this one. More...

virtual bool	contains (const Kernel::V2D &point) const
	Is a point inside this polygon. More...

	ConvexPolygon ()
	Default constructor. More...

	ConvexPolygon (const ConvexPolygon &)=default

	ConvexPolygon (ConvexPolygon &&)=default

	ConvexPolygon (Vertices vertices)
	Construct a polygon from a collection of points. More...

virtual double	determinant () const
	Compute the 'determinant' of the points. More...

void	insert (const Kernel::V2D &pt)
	Insert a new vertex. More...

void	insert (double x, double y)
	Insert a new vertex based on x,y values. More...

bool	isValid () const
	Check if polygon is valid. More...

virtual double	maxX () const
	Return the largest X value in the polygon. More...

virtual double	maxY () const
	Return the largest Y value in the polygon. More...

virtual double	minX () const
	Return the lowest X value in the polygon. More...

virtual double	minY () const
	Return the lowest Y value in the polygon. More...

virtual size_t	npoints () const
	Return the number of vertices. More...

ConvexPolygon &	operator= (const ConvexPolygon &)=default

ConvexPolygon &	operator= (ConvexPolygon &&)=default

virtual const Kernel::V2D &	operator[] (const size_t index) const
	Index access. More...

virtual ConvexPolygon	toPoly () const
	Return a new Polygon based on the current type. More...

virtual	~ConvexPolygon ()=default
	Destructor. More...

Private Member Functions
void	setup ()
	Setup the meta-data. More...

double	triangleArea (const Kernel::V2D &a, const Kernel::V2D &b, const Kernel::V2D &c) const
	Compute the area of a triangle given by 3 points. More...

Private Attributes
double	m_maxX
	Highest X value. More...

double	m_maxY
	Highest Y value. More...

double	m_minX
	Lowest X value. More...

double	m_minY
	Lowest Y value. More...

Vertices	m_vertices

Detailed Description

An implementation of a convex polygon.

It contains a list of vertices that make up a convex polygon and the list is assumed to be ordered in a clockwise manner and the polygon is assumed to be closed.

A polygon is convex if:

Every internal angle is less than or equal to 180 degrees.
Every line segment between two vertices remains inside or on the boundary of the polygon.

Definition at line 36 of file ConvexPolygon.h.

Member Typedef Documentation

◆ Vertices

using Mantid::Geometry::ConvexPolygon::Vertices = std::vector<Kernel::V2D>

Type of the point list.

Definition at line 40 of file ConvexPolygon.h.

Constructor & Destructor Documentation

◆ ConvexPolygon() [1/4]

Mantid::Geometry::ConvexPolygon::ConvexPolygon ( )

Default constructor.

Constructs a 'null' polygon with no points.

Definition at line 29 of file ConvexPolygon.cpp.

Referenced by Mantid::Geometry::Quadrilateral::toPoly().

◆ ConvexPolygon() [2/4]

Mantid::Geometry::ConvexPolygon::ConvexPolygon ( Vertices vertices )

Construct a polygon from a collection of points.

Parameters

vertices A list of points that form the polygon

Definition at line 34 of file ConvexPolygon.cpp.

References setup().

◆ ~ConvexPolygon()

virtual Mantid::Geometry::ConvexPolygon::~ConvexPolygon ( )

virtualdefault

Destructor.

◆ ConvexPolygon() [3/4]

Mantid::Geometry::ConvexPolygon::ConvexPolygon ( ConvexPolygon && )

default

◆ ConvexPolygon() [4/4]

Mantid::Geometry::ConvexPolygon::ConvexPolygon ( const ConvexPolygon & )

default

Member Function Documentation

◆ area()

double Mantid::Geometry::ConvexPolygon::area ( ) const

virtual

Compute the area of the polygon using triangulation.

As this is a convex polygon the calculation is exact. The algorithm uses one vertex as a common vertex and sums the areas of the triangles formed by this and two other vertices, moving in an anti-clockwise direction.

Returns: The area of the polygon

Reimplemented in Mantid::Geometry::Quadrilateral.

Definition at line 132 of file ConvexPolygon.cpp.

References determinant().

Referenced by Mantid::DataObjects::FractionalRebinning::calcGeneralIntersections(), Mantid::Geometry::intersection(), and Mantid::DataObjects::FractionalRebinning::rebinToOutput().

◆ at()

const Kernel::V2D & Mantid::Geometry::ConvexPolygon::at ( const size_t index ) const

virtual

Bounds-checked index access.

Return the vertex at the given index.

The index is checked for validity

Parameters

index :: An index, starting at 0

Returns: A reference to the polygon at that index

Exceptions

Exception::IndexError if the index is out of range

Reimplemented in Mantid::Geometry::Quadrilateral.

Definition at line 83 of file ConvexPolygon.cpp.

References index, m_vertices, and npoints().

◆ clear()

void Mantid::Geometry::ConvexPolygon::clear ( )

Clears all points.

Definition at line 40 of file ConvexPolygon.cpp.

References m_maxX, m_maxY, m_minX, m_minY, and m_vertices.

Referenced by Mantid::DataObjects::FractionalRebinning::calcGeneralIntersections(), and Mantid::DataObjects::FractionalRebinning::rebinToOutput().

◆ contains() [1/2]

bool Mantid::Geometry::ConvexPolygon::contains ( const ConvexPolygon & poly ) const

virtual

Is a the given polygon completely encosed by this one.

Is the given polygon completely encosed by this one.

Parameters

poly	Another polygon

Returns: True if the given polygon is enclosed by this, false otherwise

Reimplemented in Mantid::Geometry::Quadrilateral.

Definition at line 115 of file ConvexPolygon.cpp.

References contains(), and npoints().

◆ contains() [2/2]

bool Mantid::Geometry::ConvexPolygon::contains ( const Kernel::V2D & point ) const

virtual

Is a point inside this polygon.

Parameters

point :: The point to test

Returns: True if the point is inside the polygon

Reimplemented in Mantid::Geometry::Quadrilateral.

Definition at line 99 of file ConvexPolygon.cpp.

References Mantid::Geometry::classify(), m_vertices, npoints(), and Mantid::Geometry::OnLeft.

Referenced by contains(), Mantid::Geometry::Quadrilateral::contains(), and Mantid::Geometry::intersection().

◆ determinant()

double Mantid::Geometry::ConvexPolygon::determinant ( ) const

virtual

Compute the 'determinant' of the points.

Compute the determinant of the set of points as if they were contained in an (N+1)x(N+1) matrix where N=number of vertices.

Each row contains the [X,Y] values of the vertex padded with zeroes to the column length.

Returns: The determinant of the set of points

Reimplemented in Mantid::Geometry::Quadrilateral.

Definition at line 140 of file ConvexPolygon.cpp.

References m_vertices, npoints(), rhs, Mantid::Kernel::V2D::X(), and Mantid::Kernel::V2D::Y().

Referenced by area().

◆ insert() [1/2]

void Mantid::Geometry::ConvexPolygon::insert ( const Kernel::V2D & pt )

Insert a new vertex.

The point is assumed that it forms the next point in a clockwise-sense around the shape

Parameters

pt	A new point for the shape

Definition at line 52 of file ConvexPolygon.cpp.

References m_maxX, m_maxY, m_minX, m_minY, m_vertices, Mantid::Kernel::V2D::X(), and Mantid::Kernel::V2D::Y().

Referenced by insert(), and Mantid::Geometry::intersection().

◆ insert() [2/2]

void Mantid::Geometry::ConvexPolygon::insert	(	double	x,
		double	y
	)

Insert a new vertex based on x,y values.

Parameters

x	X coordinate
y	Y coordinate

Definition at line 65 of file ConvexPolygon.cpp.

References insert(), Mantid::Geometry::x, and Mantid::Geometry::y.

◆ isValid()

bool Mantid::Geometry::ConvexPolygon::isValid ( ) const

Check if polygon is valid.

Returns: True if polygon has 3 or more points

Definition at line 37 of file ConvexPolygon.cpp.

References npoints().

Referenced by Mantid::Geometry::intersection(), and Mantid::Geometry::ConvexPolygon::Iterator::Iterator().

◆ maxX()

double Mantid::Geometry::ConvexPolygon::maxX ( ) const

virtual

Return the largest X value in the polygon.

Returns: A double indicating the smallest X value in the polygon

Reimplemented in Mantid::Geometry::Quadrilateral.

Definition at line 172 of file ConvexPolygon.cpp.

References m_maxX.

Referenced by Mantid::DataObjects::FractionalRebinning::rebinToOutput().

◆ maxY()

double Mantid::Geometry::ConvexPolygon::maxY ( ) const

virtual

Return the largest Y value in the polygon.

Returns: A double indicating the smallest Y value in the polygon

Reimplemented in Mantid::Geometry::Quadrilateral.

Definition at line 184 of file ConvexPolygon.cpp.

References m_maxY.

◆ minX()

double Mantid::Geometry::ConvexPolygon::minX ( ) const

virtual

Return the lowest X value in the polygon.

Returns: A double indicating the smallest X value in the polygon

Reimplemented in Mantid::Geometry::Quadrilateral.

Definition at line 166 of file ConvexPolygon.cpp.

References m_minX.

Referenced by Mantid::DataObjects::FractionalRebinning::rebinToOutput().

◆ minY()

double Mantid::Geometry::ConvexPolygon::minY ( ) const

virtual

Return the lowest Y value in the polygon.

Return the lowest X value in the polygon.

Returns: A double indicating the smallest Y value in the polygon

Reimplemented in Mantid::Geometry::Quadrilateral.

Definition at line 178 of file ConvexPolygon.cpp.

References m_minY.

◆ npoints()

size_t Mantid::Geometry::ConvexPolygon::npoints ( ) const

virtual

Return the number of vertices.

Returns: the number of vertices

Reimplemented in Mantid::Geometry::Quadrilateral.

Definition at line 92 of file ConvexPolygon.cpp.

References m_vertices.

Referenced by at(), contains(), determinant(), Mantid::Geometry::intersection(), isValid(), and Mantid::Geometry::operator<<().

◆ operator=() [1/2]

ConvexPolygon & Mantid::Geometry::ConvexPolygon::operator= ( const ConvexPolygon & )

default

◆ operator=() [2/2]

ConvexPolygon & Mantid::Geometry::ConvexPolygon::operator= ( ConvexPolygon && )

default

◆ operator[]()

const V2D & Mantid::Geometry::ConvexPolygon::operator[] ( const size_t index ) const

virtual

Index access.

Return the vertex at the given index.

The index is assumed to be valid. See at() for a bounds-checking version. Out-of-bounds access is undefined

Parameters

index :: An index, starting at 0

Returns: A reference to the polygon at that index

Exceptions

Exception::IndexError if the index is out of range

Reimplemented in Mantid::Geometry::Quadrilateral.

Definition at line 75 of file ConvexPolygon.cpp.

References index, and m_vertices.

◆ setup()

void Mantid::Geometry::ConvexPolygon::setup ( )

private

Setup the meta-data.

Setup the meta-data: no of vertices, high/low points.

Definition at line 194 of file ConvexPolygon.cpp.

References m_maxX, m_maxY, m_minX, m_minY, m_vertices, Mantid::Geometry::x, and Mantid::Geometry::y.

Referenced by ConvexPolygon().

◆ toPoly()

ConvexPolygon Mantid::Geometry::ConvexPolygon::toPoly ( ) const

virtual

Return a new Polygon based on the current type.

Returns: A copy of the current polygon

Reimplemented in Mantid::Geometry::Quadrilateral.

Definition at line 189 of file ConvexPolygon.cpp.

Referenced by Mantid::Geometry::intersection().

◆ triangleArea()

double Mantid::Geometry::ConvexPolygon::triangleArea	(	const Kernel::V2D &	a,
		const Kernel::V2D &	b,
		const Kernel::V2D &	c
	)		const

private

Compute the area of a triangle given by 3 points.

Compute the area of a triangle given by 3 points (a,b,c) using the convention in "Computational Geometry in C" by J.

O'Rourke

Parameters

a	:: The first vertex in the set
b	:: The second vertex in the set
c	:: The third vertex in the set

Definition at line 216 of file ConvexPolygon.cpp.

References Mantid::Kernel::V2D::X(), and Mantid::Kernel::V2D::Y().

Member Data Documentation

◆ m_maxX

double Mantid::Geometry::ConvexPolygon::m_maxX

private

Highest X value.

Definition at line 122 of file ConvexPolygon.h.

Referenced by clear(), insert(), maxX(), and setup().

◆ m_maxY

double Mantid::Geometry::ConvexPolygon::m_maxY

private

Highest Y value.

Definition at line 126 of file ConvexPolygon.h.

Referenced by clear(), insert(), maxY(), and setup().

◆ m_minX

double Mantid::Geometry::ConvexPolygon::m_minX

private

Lowest X value.

Definition at line 120 of file ConvexPolygon.h.

Referenced by clear(), insert(), minX(), and setup().

◆ m_minY

double Mantid::Geometry::ConvexPolygon::m_minY

private

Lowest Y value.

Definition at line 124 of file ConvexPolygon.h.

Referenced by clear(), insert(), minY(), and setup().

◆ m_vertices

Vertices Mantid::Geometry::ConvexPolygon::m_vertices

private

Definition at line 128 of file ConvexPolygon.h.

Referenced by at(), clear(), contains(), determinant(), insert(), npoints(), operator[](), and setup().

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

Framework/Geometry/inc/MantidGeometry/Math/ConvexPolygon.h
Framework/Geometry/src/Math/ConvexPolygon.cpp

Classes

Public Types

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Member Typedef Documentation

◆ Vertices

Constructor & Destructor Documentation

◆ ConvexPolygon() [1/4]

◆ ConvexPolygon() [2/4]

◆ ~ConvexPolygon()

◆ ConvexPolygon() [3/4]

◆ ConvexPolygon() [4/4]

Member Function Documentation

◆ area()

◆ at()

◆ clear()

◆ contains() [1/2]

◆ contains() [2/2]

◆ determinant()

◆ insert() [1/2]

◆ insert() [2/2]

◆ isValid()

◆ maxX()

◆ maxY()

◆ minX()

◆ minY()

◆ npoints()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ operator[]()

◆ setup()

◆ toPoly()

◆ triangleArea()

Member Data Documentation

◆ m_maxX

◆ m_maxY

◆ m_minX

◆ m_minY

◆ m_vertices