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42 #include "qquickangledirection_p.h"
49 const qreal CONV = 0.017453292519943295;
51 \qmlclass AngleDirection QQuickAngleDirection
52 \inqmlmodule QtQuick.Particles 2
53 \ingroup qtquick-particles
55 \brief For specifying a direction that varies in angle
57 The AngledDirection element allows both the specification of a direction by angle and magnitude,
58 as well as varying the parameters by angle or magnitude.
61 \qmlproperty real QtQuick.Particles2::AngleDirection::angle
62 This property specifies the base angle for the direction.
63 The angle of this direction will vary by no more than angleVariation
66 Angle is specified by degrees clockwise from straight right.
68 The default value is zero.
71 \qmlproperty real QtQuick.Particles2::AngleDirection::magnitude
72 This property specifies the base magnitude for the direction.
73 The magnitude of this direction will vary by no more than magnitudeVariation
76 Magnitude is specified in units of pixels per second.
78 The default value is zero.
81 \qmlproperty real QtQuick.Particles2::AngleDirection::angleVariation
82 This property specifies the maximum angle variation for the direction.
83 The angle of the direction will vary by up to angleVariation clockwise
84 and anticlockwise from the value specified in angle.
86 Angle is specified by degrees clockwise from straight right.
88 The default value is zero.
91 \qmlproperty real QtQuick.Particles2::AngleDirection::magnitudeVariation
92 This property specifies the base magnitude for the direction.
93 The magnitude of this direction will vary by no more than magnitudeVariation
94 from the base magnitude.
96 Magnitude is specified in units of pixels per second.
98 The default value is zero.
100 QQuickAngleDirection::QQuickAngleDirection(QObject *parent) :
101 QQuickDirection(parent)
104 , m_angleVariation(0)
105 , m_magnitudeVariation(0)
110 const QPointF QQuickAngleDirection::sample(const QPointF &from)
114 qreal theta = m_angle*CONV - m_angleVariation*CONV + rand()/float(RAND_MAX) * m_angleVariation*CONV * 2;
115 qreal mag = m_magnitude- m_magnitudeVariation + rand()/float(RAND_MAX) * m_magnitudeVariation * 2;
116 ret.setX(mag * cos(theta));
117 ret.setY(mag * sin(theta));