CArc Class Reference

Arc shape. More...

#include <Arc.h>

Inheritance diagram for CArc:

Public Member Functions
	CArc (CArcDesc &)
	Constructor. More...
bool	PreCollide (CContactDesc &)
	Collision detection. More...
bool	PtInSector (const Vector2 &)
	Point in sector test. More...
void	GetEndPts (Vector2 &, Vector2 &)
	Get end points. More...
void	GetTangents (Vector2 &, Vector2 &)
	Get tangents. More...
Public Member Functions inherited from CCircle
	CCircle (const CCircleDesc &)
	Constructor. More...
bool	PreCollide (CContactDesc &)
	Collision detection. More...
bool	PtInCircle (const Vector2 &)
	Point in circle test. More...
Vector2	ClosestPt (const Vector2 &)
	Closest point on circle. More...
bool	Tangents (const Vector2 &, Vector2 &, Vector2 &)
	Tangents through external point. More...
bool	Tangents (CCircle *, CLineSegDesc &, CLineSegDesc &)
	Common tangents. More...
bool	Tangent (CCircle *, CLineSegDesc &)
	Common tangent. More...
float	GetRadius ()
	Get radius. More...
Public Member Functions inherited from CShape
	CShape (const CShapeDesc &)
	Constructor. More...
virtual	~CShape ()
	Destructor. More...
const eShape	GetShapeType () const
	Get shape type. More...
const eMotion	GetMotionType () const
	Get motion type. More...
const CAabb2D &	GetAABB () const
	Get AABB. More...
const bool	GetSensor () const
	Is this shape a sensor? More...
const Vector2 &	GetPos () const
	Get position. More...
void	SetPos (const Vector2 &)
	Set position. More...
void	SetAABBPoint (const Vector2 &)
	Set AABB point. More...
void	AddAABBPoint (const Vector2 &)
	Add AABB point. More...
void	SetCanCollide (bool=true)
	Turn collisions on or off. More...
const bool	GetCanCollide () const
	Get whether shape can collide. More...
virtual void	Rotate (const Vector2 &, float)
	Rotate. More...
virtual void	Reset ()
	Reset orientation. More...
virtual void	move ()
	Translate. More...
const bool	GetRotating () const
	Get whether rotating. More...
void	SetRotating (bool)
	Start or stop rotating. More...
const float	GetOrientation () const
	Get orientation. More...
const float	GetRotSpeed () const
	Get rotation speed. More...
const Vector2 &	GetRotCenter () const
	Get rotation speed. More...
const float	GetElasticity () const
	Get elasticity. More...
void	SetOrientation (float)
	Set orientation. More...
void	SetRotSpeed (float)
	Set rotation speed. More...
void	SetRotCenter (const Vector2 &)
	Set center of rotation. More...
void *	GetUserPtr () const
	Get user pointer. More...
void	SetUserPtr (void *)
	Set user pointer. More...

Protected Member Functions
void	Update ()
	Update from angles and radius. More...
float	PtToAngle (const Vector2 &)
	Point to angle.

Protected Attributes
Vector2	m_vPt0
	Point 0.
Vector2	m_vPt1
	Point 1.
float	m_fAngle0
	Angle from center to point 0.
float	m_fAngle1
	Angle from center to point 1.
Vector2	m_vTangent0
	Tangent at point 0.
Vector2	m_vTangent1
	Tangent at point 1.
Protected Attributes inherited from CCircle
float	m_fRadius = 0.0f
	Radius.
float	m_fRadiusSq = 0.0f
	Radius squared, used for faster distance calculations.
Protected Attributes inherited from CShape
eShape	m_eShapeType = eShape::Unknown
	Type of shape.
eMotion	m_eMotionType = eMotion::Static
	How shape moves.
float	m_fElasticity = 1.0f
	Elasticity, aka restitution, bounciness.
bool	m_bIsSensor = false
	Sensor only, no rebound on collision.
CAabb2D	m_cAABB
	Axially aligned bounding box in World Space.
bool	m_bCanCollide = true
	Can collide with other shapes.
float	m_fOrientation = 0.0f
	Orientation angle.
void *	m_pUser
	Spare pointer for user in case they might need one.
Vector2	m_vRotCenter
	Center of rotation.
float	m_fRotSpeed = 0.0f
	Rotation speed.
bool	m_bRotating = false
	Whether rotating.

Additional Inherited Members
Static Protected Attributes inherited from CShapeCommon
static float	m_fGravity = 0.0f
	Gravitational constant.
static float	m_fTimeStep = 0.0f
	Time step per animation frame (fictional).

Detailed Description

An arc represents a portion of the circumference of a circle bounded by a pair of angles. If the first angle is smaller than the second angle, then the arc extends from the first angle to the second angle in a counterclockwise direction. If the first angle is greater than the second angle, then the arc extends from the first angle to the second angle in a clockwise direction. If the first angle is the same as the second angle, then you are an idiot.

Constructor & Destructor Documentation

CArc()

CArc::CArc

(

CArcDesc &

r

)

Constructs an arc described by an arc descriptor.

Parameters

r	Arc descriptor.

Member Function Documentation

GetEndPts()

void CArc::GetEndPts	(	Vector2 &	p0,
		Vector2 &	p1
	)

Reader function for the end points.

Parameters

p0	[out] First end point.
p1	[out] Second end point.

GetTangents()

void CArc::GetTangents	(	Vector2 &	v0,
		Vector2 &	v1
	)

Reader function for the tangents. Tangents are returned in the same order as GetEndPoints().

Parameters

v0	[out] Tangent at fist end point.
v1	[out] Tangent at second end point.

PreCollide()

bool CArc::PreCollide ( CContactDesc &  c )

virtual

Collision detection with a dynamic circle.

Parameters

c	[in, out] Contact descriptor for this collision.

Returns

true is there was a collision.

Reimplemented from CShape.

PtInSector()

bool CArc::PtInSector

(

const Vector2 &

p

)

Draw imaginary lines from the center of this arc (meaning the center of the circle containing it) to its end points and continue them on infinitely. A point is said to be inside the sector if it is between those two lines.

Parameters

p

A point.

Returns

true if p is inside the sector defined by this arc.

Update()

void CArc::Update ( )

protected

Update the arc properties from its center, radius, and angles. The end points, tangents, and AABB are recomputed.