QBezier Class Reference

#include <qbezier_p.h>

Collaboration diagram for QBezier:

Public Member Functions
QPointF	pointAt (qreal t) const
QPointF	normalVector (qreal t) const
QPointF	derivedAt (qreal t) const
QPointF	secondDerivedAt (qreal t) const
QPolygonF	toPolygon (qreal bezier_flattening_threshold=0.5) const
void	addToPolygon (QPolygonF *p, qreal bezier_flattening_threshold=0.5) const
void	addToPolygon (QDataBuffer< QPointF > &polygon, qreal bezier_flattening_threshold) const
QPolygonF	toQuadratics (qreal errorLimit=0.2) const
void	addToQuadratics (QPolygonF *p, qreal tspan=1.0, qreal errorLimit=0.2) const
int	inflectionPoints (qreal *tpoints) const
QRectF	bounds () const
qreal	length (qreal error=0.01) const
void	addIfClose (qreal *length, qreal error) const
qreal	tAtLength (qreal len) const
int	stationaryYPoints (qreal &t0, qreal &t1) const
qreal	tForY (qreal t0, qreal t1, qreal y) const
QPointF	pt1 () const
QPointF	pt2 () const
QPointF	pt3 () const
QPointF	pt4 () const
QBezier	mapBy (const QTransform &transform) const
QPointF	midPoint () const
QLineF	midTangent () const
QLineF	startTangent () const
QLineF	endTangent () const
void	parameterSplitLeft (qreal t, QBezier *left)
std::pair< QBezier, QBezier >	split () const
int	shifted (QBezier *curveSegments, int maxSegmets, qreal offset, float threshold) const
QBezier	bezierOnInterval (qreal t0, qreal t1) const
QBezier	getSubRange (qreal t0, qreal t1) const

Static Public Member Functions
static QBezier	fromPoints (const QPointF &p1, const QPointF &p2, const QPointF &p3, const QPointF &p4)
static void	coefficients (qreal t, qreal &a, qreal &b, qreal &c, qreal &d)

Public Attributes
qreal	x1
qreal	y1
qreal	x2
qreal	y2
qreal	x3
qreal	y3
qreal	x4
qreal	y4

Detailed Description

Definition at line 31 of file qbezier_p.h.

Member Function Documentation

addIfClose()

void QBezier::addIfClose	(	qreal *	length,
		qreal	error
	)		const

Definition at line 533 of file qbezier.cpp.

References error, QLineF::length(), split(), x3, x4, y3, and y4.

Referenced by length().

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addToPolygon() [1/2]

void QBezier::addToPolygon	(	QDataBuffer< QPointF > &	polygon,
		qreal	bezier_flattening_threshold
	)		const

Definition at line 101 of file qbezier.cpp.

References d, qAbs(), and y4.

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addToPolygon() [2/2]

void QBezier::addToPolygon	(	QPolygonF *	p,
		qreal	bezier_flattening_threshold = 0.5
	)		const

Definition at line 65 of file qbezier.cpp.

References d, qAbs(), and y4.

Referenced by QOutlineMapper::curveTo(), toPolygon(), and QPainterPath::toSubpathPolygons().

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addToQuadratics()

void QBezier::addToQuadratics	(	QPolygonF *	p,
		qreal	tspan = 1.0,
		qreal	errorLimit = 0.2
	)		const

Definition at line 179 of file qbezier.cpp.

References pt4(), Q_ASSERT, quadraticForCubic(), scoreQuadratic(), and split().

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bezierOnInterval()

QBezier QBezier::bezierOnInterval	(	qreal	t0,
		qreal	t1
	)		const

Definition at line 680 of file qbezier.cpp.

References parameterSplitLeft(), and t0.

Referenced by qt_toQuadratics(), and toQuadratics().

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bounds()

QRectF QBezier::bounds

(

)

const

Definition at line 239 of file qbezier.cpp.

References x1, x2, x3, x4, y1, y2, y3, and y4.

Referenced by QPathSegments::addPath(), QOutlineMapper::curveTo(), qt_isect_curve_horizontal(), qt_isect_curve_vertical(), qt_painterpath_isect_curve(), and shift().

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coefficients()

void QBezier::coefficients ( qreal  t, qreal &  a, qreal &  b, qreal &  c, qreal &  d  )

inlinestatic

Definition at line 121 of file qbezier_p.h.

References d.

Referenced by qt_find_ellipse_coords(), and tForY().

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derivedAt()

QPointF QBezier::derivedAt ( qreal  t ) const

inline

Definition at line 167 of file qbezier_p.h.

References d, x3, x4, y3, and y4.

endTangent()

QLineF QBezier::endTangent ( ) const

inline

Definition at line 111 of file qbezier_p.h.

References QLineF::isNull(), pt1(), pt2(), pt3(), and pt4().

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fromPoints()

static QBezier QBezier::fromPoints ( const QPointF &  p1, const QPointF &  p2, const QPointF &  p3, const QPointF &  p4  )

inlinestatic

Definition at line 34 of file qbezier_p.h.

References p1, p2, QPointF::x(), and QPointF::y().

Referenced by QPathSegments::addPath(), QOpenGL2PEXVertexArray::addPath(), bezierAtT(), QPainterPath::contains(), cubicTo_clipped(), QOutlineMapper::curveTo(), QuadPath::fromPainterPath(), QTriangulator< T >::initialize(), QPainterPath::length(), mapBy(), QSubpathFlatIterator::next(), nextBezier(), QPainterPath::percentAtLength(), QDashedStrokeProcessor::process(), qt_curves_for_arc(), qt_painterpath_check_crossing(), qt_stroke_side(), shift(), split(), and QPainterPath::toSubpathPolygons().

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getSubRange()

QBezier QBezier::getSubRange	(	qreal	t0,
		qreal	t1
	)		const

Definition at line 45 of file qbezier.cpp.

References parameterSplitLeft(), and qFuzzyIsNull().

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inflectionPoints()

int QBezier::inflectionPoints

(

qreal *

tpoints

)

const

Definition at line 195 of file qbezier.cpp.

References QLineF::angle(), mapBy(), pt1(), pt4(), Q_ASSERT, qFuzzyCompare(), qFuzzyIsNull(), qIsFinite(), qSqrt(), qSwap(), QTransform::rotate(), and QTransform::translate().

Referenced by toQuadratics().

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length()

qreal QBezier::length

(

qreal

error = 0.01

)

const

Definition at line 524 of file qbezier.cpp.

References addIfClose(), and error.

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mapBy()

QBezier QBezier::mapBy

(

const QTransform &

transform

)

const

Definition at line 40 of file qbezier.cpp.

References fromPoints(), pt1(), pt2(), pt3(), and pt4().

Referenced by inflectionPoints(), and qt_getInflectionPoints().

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midPoint()

QPointF QBezier::midPoint ( ) const

inline

Definition at line 88 of file qbezier_p.h.

References x3, x4, y3, and y4.

Referenced by midTangent().

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midTangent()

QLineF QBezier::midTangent ( ) const

inline

Definition at line 93 of file qbezier_p.h.

References dir, midPoint(), pointAt(), QPointF::x(), x3, x4, QPointF::y(), y3, and y4.

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normalVector()

QPointF QBezier::normalVector ( qreal  t ) const

inline

Definition at line 157 of file qbezier_p.h.

References x3, x4, y3, and y4.

Referenced by good_offset().

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parameterSplitLeft()

void QBezier::parameterSplitLeft ( qreal  t, QBezier *  left  )

inline

Definition at line 210 of file qbezier_p.h.

References x1, x2, x3, x4, y1, y2, y3, and y4.

Referenced by bezierOnInterval(), getSubRange(), and qt_addToQuadratics().

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pointAt()

QPointF QBezier::pointAt ( qreal  t ) const

inline

Definition at line 132 of file qbezier_p.h.

References x3, x4, y3, and y4.

Referenced by QPathSegments::addPath(), good_offset(), midTangent(), and tForY().

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pt1()

QPointF QBezier::pt1 ( ) const

inline

Definition at line 63 of file qbezier_p.h.

Referenced by endTangent(), inflectionPoints(), isLine(), mapBy(), qt_getInflectionPoints(), qt_painterpath_isect_curve(), qt_stroke_side(), split(), startTangent(), and toQuadratics().

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pt2()

QPointF QBezier::pt2 ( ) const

inline

Definition at line 64 of file qbezier_p.h.

Referenced by endTangent(), isLine(), mapBy(), qt_stroke_side(), split(), and startTangent().

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pt3()

QPointF QBezier::pt3 ( ) const

inline

Definition at line 65 of file qbezier_p.h.

Referenced by endTangent(), isLine(), mapBy(), qt_stroke_side(), split(), and startTangent().

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pt4()

QPointF QBezier::pt4 ( ) const

inline

Definition at line 66 of file qbezier_p.h.

Referenced by addToQuadratics(), endTangent(), inflectionPoints(), isLine(), mapBy(), qt_getInflectionPoints(), qt_painterpath_isect_curve(), qt_stroke_side(), split(), and startTangent().

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secondDerivedAt()

QPointF QBezier::secondDerivedAt ( qreal  t ) const

inline

Definition at line 182 of file qbezier_p.h.

References d, x3, x4, y3, and y4.

shifted()

int QBezier::shifted	(	QBezier *	curveSegments,
		int	maxSegmets,
		qreal	offset,
		float	threshold
	)		const

Definition at line 457 of file qbezier.cpp.

References addCircle(), Circle, Discard, o, Ok, Q_ASSERT, qFuzzyCompare(), shift(), Split, x3, x4, y3, and y4.

Referenced by qt_stroke_side().

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split()

std::pair< QBezier, QBezier > QBezier::split ( ) const

inline

Definition at line 193 of file qbezier_p.h.

References fromPoints(), pt1(), pt2(), pt3(), and pt4().

Referenced by addIfClose(), addToQuadratics(), qt_isect_curve_horizontal(), qt_isect_curve_vertical(), and qt_painterpath_isect_curve().

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startTangent()

QLineF QBezier::startTangent ( ) const

inline

Definition at line 101 of file qbezier_p.h.

References QLineF::isNull(), pt1(), pt2(), pt3(), and pt4().

Referenced by qt_stroke_side().

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stationaryYPoints()

int QBezier::stationaryYPoints	(	qreal &	t0,
		qreal &	t1
	)		const

Definition at line 598 of file qbezier.cpp.

References qFuzzyIsNull(), qSqrt(), qSwap(), t0, t1, y2, y3, and y4.

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tAtLength()

qreal QBezier::tAtLength

(

qreal

len

)

const

Definition at line 647 of file qbezier.cpp.

References error, qAbs(), and qFuzzyCompare().

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tForY()

qreal QBezier::tForY	(	qreal	t0,
		qreal	t1,
		qreal	y
	)		const

Definition at line 556 of file qbezier.cpp.

References coefficients(), d, e, pointAt(), Q_ASSERT, qAbs(), qSwap(), t0, t1, QPointF::y(), y3, and y4.

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toPolygon()

QT_BEGIN_NAMESPACE QPolygonF QBezier::toPolygon

(

qreal

bezier_flattening_threshold = 0.5

)

const

Definition at line 21 of file qbezier.cpp.

References addToPolygon().

Referenced by cubicTo_clipped(), QTriangulator< T >::initialize(), and QSubpathFlatIterator::next().

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toQuadratics()

QPolygonF QBezier::toQuadratics

(

qreal

errorLimit = 0.2

)

const

Definition at line 137 of file qbezier.cpp.

References bezierOnInterval(), i, inflectionPoints(), pt1(), and t1.

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Member Data Documentation

x1

qreal QBezier::x1

Definition at line 85 of file qbezier_p.h.

Referenced by QPainterPath::angleAtPercent(), bounds(), parameterSplitLeft(), shift(), and QPainterPath::slopeAtPercent().

x2

qreal QBezier::x2

Definition at line 85 of file qbezier_p.h.

Referenced by QPainterPath::angleAtPercent(), bounds(), parameterSplitLeft(), shift(), and QPainterPath::slopeAtPercent().

x3

qreal QBezier::x3

Definition at line 85 of file qbezier_p.h.

Referenced by addIfClose(), QPainterPath::angleAtPercent(), bounds(), derivedAt(), midPoint(), midTangent(), normalVector(), parameterSplitLeft(), pointAt(), secondDerivedAt(), shift(), shifted(), and QPainterPath::slopeAtPercent().

x4

qreal QBezier::x4

Definition at line 85 of file qbezier_p.h.

Referenced by addIfClose(), QPainterPath::angleAtPercent(), bounds(), derivedAt(), midPoint(), midTangent(), normalVector(), parameterSplitLeft(), pointAt(), secondDerivedAt(), shift(), shifted(), and QPainterPath::slopeAtPercent().

y1

qreal QBezier::y1

Definition at line 85 of file qbezier_p.h.

Referenced by QPainterPath::angleAtPercent(), bounds(), parameterSplitLeft(), shift(), and QPainterPath::slopeAtPercent().

y2

qreal QBezier::y2

Definition at line 85 of file qbezier_p.h.

Referenced by QPainterPath::angleAtPercent(), bounds(), parameterSplitLeft(), shift(), QPainterPath::slopeAtPercent(), and stationaryYPoints().

y3

qreal QBezier::y3

Definition at line 85 of file qbezier_p.h.

Referenced by addIfClose(), QPainterPath::angleAtPercent(), bounds(), derivedAt(), midPoint(), midTangent(), normalVector(), parameterSplitLeft(), pointAt(), secondDerivedAt(), shift(), shifted(), QPainterPath::slopeAtPercent(), stationaryYPoints(), and tForY().

y4

qreal QBezier::y4

Definition at line 85 of file qbezier_p.h.

Referenced by addIfClose(), addToPolygon(), addToPolygon(), QPainterPath::angleAtPercent(), bounds(), derivedAt(), midPoint(), midTangent(), normalVector(), parameterSplitLeft(), pointAt(), secondDerivedAt(), shift(), shifted(), QPainterPath::slopeAtPercent(), stationaryYPoints(), and tForY().

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

• qtbase/src/gui/painting/qbezier_p.h
• qtbase/src/gui/painting/qbezier.cpp