CGPointExtension.h File Reference

#import "ccMacros.h"
#import <CoreGraphics/CGGeometry.h>
#import <math.h>
#import <objc/objc.h>

Include dependency graph for CGPointExtension.h:

Functions
static CGPoint	ccp (CGFloat x, CGFloat y)
static CGPoint	ccpNeg (const CGPoint v)
static CGPoint	ccpAdd (const CGPoint v1, const CGPoint v2)
static CGPoint	ccpSub (const CGPoint v1, const CGPoint v2)
static CGPoint	ccpMult (const CGPoint v, const CGFloat s)
static CGPoint	ccpMidpoint (const CGPoint v1, const CGPoint v2)
static CGFloat	ccpDot (const CGPoint v1, const CGPoint v2)
static CGFloat	ccpCross (const CGPoint v1, const CGPoint v2)
static CGPoint	ccpPerp (const CGPoint v)
static CGPoint	ccpRPerp (const CGPoint v)
static CGPoint	ccpProject (const CGPoint v1, const CGPoint v2)
static CGPoint	ccpRotate (const CGPoint v1, const CGPoint v2)
static CGPoint	ccpUnrotate (const CGPoint v1, const CGPoint v2)
static CGFloat	ccpLengthSQ (const CGPoint v)
static CGFloat	ccpDistanceSQ (const CGPoint p1, const CGPoint p2)
CGFloat	ccpLength (const CGPoint v)
CGFloat	ccpDistance (const CGPoint v1, const CGPoint v2)
CGPoint	ccpNormalize (const CGPoint v)
CGPoint	ccpForAngle (const CGFloat a)
CGFloat	ccpToAngle (const CGPoint v)
float	clampf (float value, float min_inclusive, float max_inclusive)
CGPoint	ccpClamp (CGPoint p, CGPoint from, CGPoint to)
CGPoint	ccpFromSize (CGSize s)
CGPoint	ccpCompOp (CGPoint p, float(*opFunc)(float))
CGPoint	ccpLerp (CGPoint a, CGPoint b, float alpha)
BOOL	ccpFuzzyEqual (CGPoint a, CGPoint b, float variance)
CGPoint	ccpCompMult (CGPoint a, CGPoint b)
float	ccpAngleSigned (CGPoint a, CGPoint b)
float	ccpAngle (CGPoint a, CGPoint b)
CGPoint	ccpRotateByAngle (CGPoint v, CGPoint pivot, float angle)
BOOL	ccpLineIntersect (CGPoint p1, CGPoint p2, CGPoint p3, CGPoint p4, float *s, float *t)
BOOL	ccpSegmentIntersect (CGPoint A, CGPoint B, CGPoint C, CGPoint D)
CGPoint	ccpIntersectPoint (CGPoint A, CGPoint B, CGPoint C, CGPoint D)

---

Detailed Description

CGPoint extensions based on Chipmunk's cpVect file. These extensions work both with CGPoint and cpVect.

The "ccp" prefix means: "CoCos2d Point"

Examples:

• ccpAdd( ccp(1,1), ccp(2,2) ); // preferred cocos2d way
• ccpAdd( CGPointMake(1,1), CGPointMake(2,2) ); // also ok but more verbose

• cpvadd( cpv(1,1), cpv(2,2) ); // way of the chipmunk
  • ccpAdd( cpv(1,1), cpv(2,2) ); // mixing chipmunk and cocos2d (avoid)
  • cpvadd( CGPointMake(1,1), CGPointMake(2,2) ); // mixing chipmunk and CG (avoid)

---

Function Documentation

static CGPoint ccp	(	CGFloat	x,
		CGFloat	y
	)		[inline, static]

Helper macro that creates a CGPoint

Returns:

CGPoint

Since:

v0.7.2

static CGPoint ccpAdd	(	const CGPoint	v1,
		const CGPoint	v2
	)		[inline, static]

Calculates sum of two points.

Returns:

CGPoint

Since:

v0.7.2

float ccpAngle	(	CGPoint	a,
		CGPoint	b
	)

Returns:

the angle in radians between two vector directions

Since:

v0.99.1

float ccpAngleSigned	(	CGPoint	a,
		CGPoint	b
	)

Returns:

the signed angle in radians between two vector directions

Since:

v0.99.1

CGPoint ccpClamp	(	CGPoint	p,
		CGPoint	from,
		CGPoint	to
	)

Clamp a point between from and to.

Since:

v0.99.1

CGPoint ccpCompMult	(	CGPoint	a,
		CGPoint	b
	)

Multiplies a nd b components, a.x*b.x, a.y*b.y

Returns:

a component-wise multiplication

Since:

v0.99.1

CGPoint ccpCompOp	(	CGPoint	p,
		float(*)(float)	opFunc
	)

Run a math operation function on each point component absf, fllorf, ceilf, roundf any function that has the signature: float func(float); For example: let's try to take the floor of x,y ccpCompOp(p,floorf);

Since:

v0.99.1

static CGFloat ccpCross	(	const CGPoint	v1,
		const CGPoint	v2
	)		[inline, static]

Calculates cross product of two points.

Returns:

CGFloat

Since:

v0.7.2

CGFloat ccpDistance	(	const CGPoint	v1,
		const CGPoint	v2
	)

Calculates the distance between two points

Returns:

CGFloat

Since:

v0.7.2

static CGFloat ccpDistanceSQ	(	const CGPoint	p1,
		const CGPoint	p2
	)		[inline, static]

Calculates the square distance between two points (not calling sqrt() )

Returns:

CGFloat

Since:

v1.1

static CGFloat ccpDot	(	const CGPoint	v1,
		const CGPoint	v2
	)		[inline, static]

Calculates dot product of two points.

Returns:

CGFloat

Since:

v0.7.2

CGPoint ccpForAngle

(

const CGFloat

a

)

Converts radians to a normalized vector.

Returns:

CGPoint

Since:

v0.7.2

CGPoint ccpFromSize

(

CGSize

s

)

Quickly convert CGSize to a CGPoint

Since:

v0.99.1

BOOL ccpFuzzyEqual	(	CGPoint	a,
		CGPoint	b,
		float	variance
	)

Returns:

if points have fuzzy equality which means equal with some degree of variance.

Since:

v0.99.1

CGFloat ccpLength

(

const CGPoint

v

)

Calculates distance between point an origin

Returns:

CGFloat

Since:

v0.7.2

static CGFloat ccpLengthSQ

(

const CGPoint

v

)

[inline, static]

Calculates the square length of a CGPoint (not calling sqrt() )

Returns:

CGFloat

Since:

v0.7.2

CGPoint ccpLerp	(	CGPoint	a,
		CGPoint	b,
		float	alpha
	)

Linear Interpolation between two points a and b

Returns:

alpha == 0 ? a alpha == 1 ? b otherwise a value between a..b

Since:

v0.99.1

BOOL ccpLineIntersect	(	CGPoint	p1,
		CGPoint	p2,
		CGPoint	p3,
		CGPoint	p4,
		float *	s,
		float *	t
	)

A general line-line intersection test

Parameters:

p1	is the startpoint for the first line P1 = (p1 - p2)
p2	is the endpoint for the first line P1 = (p1 - p2)
p3	is the startpoint for the second line P2 = (p3 - p4)
p4	is the endpoint for the second line P2 = (p3 - p4)
s	is the range for a hitpoint in P1 (pa = p1 + s*(p2 - p1))
t	is the range for a hitpoint in P3 (pa = p2 + t*(p4 - p3))

Returns:

bool indicating successful intersection of a line note that to truly test intersection for segments we have to make sure that s & t lie within [0..1] and for rays, make sure s & t > 0 the hit point is p3 + t * (p4 - p3); the hit point also is p1 + s * (p2 - p1);

Since:

v0.99.1

static CGPoint ccpMidpoint	(	const CGPoint	v1,
		const CGPoint	v2
	)		[inline, static]

Calculates midpoint between two points.

Returns:

CGPoint

Since:

v0.7.2

static CGPoint ccpMult	(	const CGPoint	v,
		const CGFloat	s
	)		[inline, static]

Returns point multiplied by given factor.

Returns:

CGPoint

Since:

v0.7.2

static CGPoint ccpNeg

(

const CGPoint

v

)

[inline, static]

Returns opposite of point.

Returns:

CGPoint

Since:

v0.7.2

CGPoint ccpNormalize

(

const CGPoint

v

)

Returns point multiplied to a length of 1.

Returns:

CGPoint

Since:

v0.7.2

static CGPoint ccpPerp

(

const CGPoint

v

)

[inline, static]

Calculates perpendicular of v, rotated 90 degrees counter-clockwise -- cross(v, perp(v)) >= 0

Returns:

CGPoint

Since:

v0.7.2

static CGPoint ccpProject	(	const CGPoint	v1,
		const CGPoint	v2
	)		[inline, static]

Calculates the projection of v1 over v2.

Returns:

CGPoint

Since:

v0.7.2

static CGPoint ccpRotate	(	const CGPoint	v1,
		const CGPoint	v2
	)		[inline, static]

Rotates two points.

Returns:

CGPoint

Since:

v0.7.2

CGPoint ccpRotateByAngle	(	CGPoint	v,
		CGPoint	pivot,
		float	angle
	)

Rotates a point counter clockwise by the angle around a pivot

Parameters:

v	is the point to rotate
pivot	is the pivot, naturally
angle	is the angle of rotation cw in radians

Returns:

the rotated point

Since:

v0.99.1

static CGPoint ccpRPerp

(

const CGPoint

v

)

[inline, static]

Calculates perpendicular of v, rotated 90 degrees clockwise -- cross(v, rperp(v)) <= 0

Returns:

CGPoint

Since:

v0.7.2

static CGPoint ccpSub	(	const CGPoint	v1,
		const CGPoint	v2
	)		[inline, static]

Calculates difference of two points.

Returns:

CGPoint

Since:

v0.7.2

CGFloat ccpToAngle

(

const CGPoint

v

)

Converts a vector to radians.

Returns:

CGFloat

Since:

v0.7.2

static CGPoint ccpUnrotate	(	const CGPoint	v1,
		const CGPoint	v2
	)		[inline, static]

Unrotates two points.

Returns:

CGPoint

Since:

v0.7.2

float clampf	(	float	value,
		float	min_inclusive,
		float	max_inclusive
	)

Clamp a value between from and to.

Since:

v0.99.1