Sword25::Polygon Class Reference

Eine Polygonklasse. More...

#include <polygon.h>

Inheritance diagram for Sword25::Polygon:

Public Member Functions
	Polygon ()
	Polygon (const Polygon &other)
	Polygon (InputPersistenceBlock &reader)
	Polygon (int vertexCount_, const Vertex *vertices_)
	~Polygon () override
bool	init (int vertexCount_, const Vertex *vertices_)
bool	isCW () const
bool	isCCW () const
bool	isPointInPolygon (const Vertex &vertex, bool borderBelongsToPolygon=true) const
bool	isPointInPolygon (int x, int y, bool borderBelongsToPolygon=true) const
Vertex	getCentroid () const
bool	isLineInterior (const Vertex &a, const Vertex &b) const
bool	isLineExterior (const Vertex &a, const Vertex &b) const
void	ensureCWOrder ()
void	ensureCCWOrder ()
void	reverseVertexOrder ()
void	operator+= (const Vertex &delta)
bool	persist (OutputPersistenceBlock &writer) override
bool	unpersist (InputPersistenceBlock &reader) override
Polygon &	operator= (const Polygon &p)

Public Attributes
int32	vertexCount
	Specifies the number of Vertecies in the Vertecies array.
Vertex *	vertices
	COntains the Vertecies of the polygon.

Detailed Description

Eine Polygonklasse.

Constructor & Destructor Documentation

Polygon() [1/4]

Sword25::Polygon::Polygon

(

)

Creates an object of type #BS_Polygon, containing 0 Vertecies.

With the method Init(), Vertices can be added in later

Polygon() [2/4]

Sword25::Polygon::Polygon

(

const Polygon &

other

)

Copy constructor

Polygon() [3/4]

Sword25::Polygon::Polygon

(

InputPersistenceBlock &

reader

)

Creates a polygon using persisted data

Polygon() [4/4]

Sword25::Polygon::Polygon	(	int	vertexCount_,
		const Vertex *	vertices_
	)

Creaes an object of type #BS_Polygon, and assigns Vertices to it

Parameters

VertexCount	The number of vertices being passed
Vertecies	An array of BS_Vertex objects representing the vertices in the polygon.

Remarks

The Vertecies that define a polygon must not have any self-intersections. If the polygon does have self-intersections, then an empty polygon object is created.

~Polygon()

Sword25::Polygon::~Polygon ( )

override

Deletes the BS_Polygon object

Member Function Documentation

init()

bool Sword25::Polygon::init	(	int	vertexCount_,
		const Vertex *	vertices_
	)

Initializes the BS_Polygon with a list of Vertecies.

The Vertices need to define a polygon must not have self-intersections. If a polygon already has verticies, this will re-initialize it with the new list.

Parameters

VertexCount	The number of vertices being passed
Vertecies	An array of BS_Vertex objects representing the vertices in the polygon.

Returns

Returns false if the Vertecies have self-intersections. In this case, the object is not initialized.

isCW()

bool Sword25::Polygon::isCW

(

)

const

Checks whether the Vertecies of the polygon are arranged in a clockwise direction.

Returns

Returns true if the Vertecies of the polygon are arranged clockwise or co-planar. Returns false if the Vertecies of the polygon are arrange counter-clockwise.

Remarks

This method only returns a meaningful result if the polygon has at least three Vertecies.

isCCW()

bool Sword25::Polygon::isCCW

(

)

const

Checks whether the Vertices of the polygon are arranged in a counter-clockwise direction.

Returns

Returns true if the Vertecies of the polygon are arranged counter-clockwise. Returns false if the Vertecies of the polygon are arranged clockwise or co-planar.

Remarks

This method only returns a meaningful result if the polygon has at least three Vertecies.

isPointInPolygon() [1/2]

bool Sword25::Polygon::isPointInPolygon	(	const Vertex &	vertex,
		bool	borderBelongsToPolygon = true
	)		const

Checks whether a point is inside the polygon

Parameters

Vertex	A Vertex with the co-ordinates of the point to be tested.
BorderBelongsToPolygon	Specifies whether the edge of the polygon should be considered

Returns

Returns true if the point is inside the polygon, false if it is outside.

isPointInPolygon() [2/2]

bool Sword25::Polygon::isPointInPolygon	(	int	x,
		int	y,
		bool	borderBelongsToPolygon = true
	)		const

Checks whether a point is inside the polygon

Parameters

X	The X position of the point
Y	The Y position of the point
BorderBelongsToPolygon	Specifies whether the edge of the polygon should be considered

Returns

Returns true if the point is inside the polygon, false if it is outside.

getCentroid()

Vertex Sword25::Polygon::getCentroid

(

)

const

Returns the focus/centroid of the polygon

ensureCWOrder()

void Sword25::Polygon::ensureCWOrder

(

)

Ensures that the Vertecies of the polygon are arranged in a clockwise direction

ensureCCWOrder()

void Sword25::Polygon::ensureCCWOrder

(

)

Ensures that the Vertecies of the polygon are arranged in a counter-clockwise direction

reverseVertexOrder()

void Sword25::Polygon::reverseVertexOrder

(

)

Reverses the Vertecies order.

operator+=()

void Sword25::Polygon::operator+=

(

const Vertex &

delta

)

Moves the polygon.

Parameters

Delta

The vertex around the polygon to be moved.

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

• engines/sword25/math/polygon.h