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42 #include "qquickangledirection_p.h"
49 const qreal CONV = 0.017453292519943295;
51 \qmlclass AngleDirection QQuickAngleDirection
52 \inqmlmodule QtQuick.Particles 2
54 \brief The AngleDirection element allows you to specify a direction that varies in angle
56 The AngledDirection element allows both the specification of a direction by angle and magnitude,
57 as well as varying the parameters by angle or magnitude.
60 \qmlproperty real QtQuick.Particles2::AngleDirection::angle
61 This property specifies the base angle for the direction.
62 The angle of this direction will vary by no more than angleVariation
65 Angle is specified by degrees clockwise from straight right.
67 The default value is zero.
70 \qmlproperty real QtQuick.Particles2::AngleDirection::magnitude
71 This property specifies the base magnitude for the direction.
72 The magnitude of this direction will vary by no more than magnitudeVariation
75 Magnitude is specified in units of pixels per second.
77 The default value is zero.
80 \qmlproperty real QtQuick.Particles2::AngleDirection::angleVariation
81 This property specifies the maximum angle variation for the direction.
82 The angle of the direction will vary by up to angleVariation clockwise
83 and anticlockwise from the value specified in angle.
85 Angle is specified by degrees clockwise from straight right.
87 The default value is zero.
90 \qmlproperty real QtQuick.Particles2::AngleDirection::magnitudeVariation
91 This property specifies the base magnitude for the direction.
92 The magnitude of this direction will vary by no more than magnitudeVariation
93 from the base magnitude.
95 Magnitude is specified in units of pixels per second.
97 The default value is zero.
99 QQuickAngleDirection::QQuickAngleDirection(QObject *parent) :
100 QQuickDirection(parent)
103 , m_angleVariation(0)
104 , m_magnitudeVariation(0)
109 const QPointF QQuickAngleDirection::sample(const QPointF &from)
113 qreal theta = m_angle*CONV - m_angleVariation*CONV + rand()/float(RAND_MAX) * m_angleVariation*CONV * 2;
114 qreal mag = m_magnitude- m_magnitudeVariation + rand()/float(RAND_MAX) * m_magnitudeVariation * 2;
115 ret.setX(mag * cos(theta));
116 ret.setY(mag * sin(theta));