Circle Class Reference

Represents a 2D circle with centre and radius, supporting geometric queries. More...

#include <circle.h>

Public Member Functions
	Circle ()
	Default constructor — creates a zero-radius circle at the origin.
	Circle (const QPointF center, double radius)
	Construct a circle from a centre point and radius.
QPointF	center () const
	Return the centre of the circle.
void	setCenter (const QPointF &value)
	Set the centre of the circle.
double	radius () const
	Return the radius of the circle.
void	setRadius (double value)
	Set the radius of the circle.
double	circumference () const
	Return the circumference of the circle.
double	diameter () const
	Return the diameter of the circle.
double	area () const
	Return the area of the circle.
bool	intersects (const Line &line) const
	Test whether a line intersects this circle.
int	intersects (const Line &line, QPointF &intersection1, QPointF &intersection2) const
	Find the intersection points of a line with this circle.
QString	toString () const
	Format the circle as a human-readable string.

Static Public Member Functions
static Circle	fromThreePoints (const Point &a, const Point &b, const Point &c)
	Construct the unique circle passing through three non-collinear points.

Detailed Description

Represents a 2D circle with centre and radius, supporting geometric queries.

Definition at line 16 of file circle.h.

Constructor & Destructor Documentation

Circle() [1/2]

Circle::Circle ( )

inline

Default constructor — creates a zero-radius circle at the origin.

Definition at line 20 of file circle.h.

Circle() [2/2]

Circle::Circle ( const QPointF  center, double  radius  )

inline

Construct a circle from a centre point and radius.

Parameters

center	Centre of the circle
radius	Radius of the circle

Definition at line 27 of file circle.h.

Member Function Documentation

area()

double Circle::area

(

)

const

Return the area of the circle.

Returns

Area (pi * radius^2)

center()

QPointF Circle::center ( ) const

inline

Return the centre of the circle.

Returns

Centre QPointF

Definition at line 43 of file circle.h.

circumference()

double Circle::circumference

(

)

const

Return the circumference of the circle.

Returns

Circumference (2 * pi * radius)

diameter()

double Circle::diameter

(

)

const

Return the diameter of the circle.

Returns

Diameter (2 * radius)

fromThreePoints()

static Circle Circle::fromThreePoints ( const Point &  a, const Point &  b, const Point &  c  )

static

Construct the unique circle passing through three non-collinear points.

Parameters

a	First point on the circle
b	Second point on the circle
c	Third point on the circle

Returns

Circumscribed circle, or an invalid circle if points are collinear

intersects() [1/2]

bool Circle::intersects

(

const Line &

line

)

const

Test whether a line intersects this circle.

Parameters

line	Line segment to test

Returns

true if the line intersects or is tangent to the circle

intersects() [2/2]

int Circle::intersects	(	const Line &	line,
		QPointF &	intersection1,
		QPointF &	intersection2
	)		const

Find the intersection points of a line with this circle.

Parameters

line	Line segment to intersect
intersection1	Output for the first intersection point
intersection2	Output for the second intersection point

Returns

Number of intersection points (0, 1, or 2)

radius()

double Circle::radius ( ) const

inline

Return the radius of the circle.

Returns

Radius value

Definition at line 55 of file circle.h.

setCenter()

void Circle::setCenter ( const QPointF &  value )

inline

Set the centre of the circle.

Parameters

value

New centre point

Definition at line 49 of file circle.h.

setRadius()

void Circle::setRadius ( double  value )

inline

Set the radius of the circle.

Parameters

value

New radius value

Definition at line 61 of file circle.h.

toString()

QString Circle::toString

(

)

const

Format the circle as a human-readable string.

Returns

String representation of centre and radius

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

• include/Kanoop/geometry/circle.h