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42 #include "qquickangledirection_p.h"
49 const qreal CONV = 0.017453292519943295;
51 \qmltype AngleDirection
52 \instantiates QQuickAngleDirection
53 \inqmlmodule QtQuick.Particles 2
54 \ingroup qtquick-particles
56 \brief For specifying a direction that varies in angle
58 The AngledDirection element allows both the specification of a direction by angle and magnitude,
59 as well as varying the parameters by angle or magnitude.
62 \qmlproperty real QtQuick.Particles2::AngleDirection::angle
63 This property specifies the base angle for the direction.
64 The angle of this direction will vary by no more than angleVariation
67 Angle is specified by degrees clockwise from straight right.
69 The default value is zero.
72 \qmlproperty real QtQuick.Particles2::AngleDirection::magnitude
73 This property specifies the base magnitude for the direction.
74 The magnitude of this direction will vary by no more than magnitudeVariation
77 Magnitude is specified in units of pixels per second.
79 The default value is zero.
82 \qmlproperty real QtQuick.Particles2::AngleDirection::angleVariation
83 This property specifies the maximum angle variation for the direction.
84 The angle of the direction will vary by up to angleVariation clockwise
85 and anticlockwise from the value specified in angle.
87 Angle is specified by degrees clockwise from straight right.
89 The default value is zero.
92 \qmlproperty real QtQuick.Particles2::AngleDirection::magnitudeVariation
93 This property specifies the base magnitude for the direction.
94 The magnitude of this direction will vary by no more than magnitudeVariation
95 from the base magnitude.
97 Magnitude is specified in units of pixels per second.
99 The default value is zero.
101 QQuickAngleDirection::QQuickAngleDirection(QObject *parent) :
102 QQuickDirection(parent)
105 , m_angleVariation(0)
106 , m_magnitudeVariation(0)
111 const QPointF QQuickAngleDirection::sample(const QPointF &from)
115 qreal theta = m_angle*CONV - m_angleVariation*CONV + rand()/float(RAND_MAX) * m_angleVariation*CONV * 2;
116 qreal mag = m_magnitude- m_magnitudeVariation + rand()/float(RAND_MAX) * m_magnitudeVariation * 2;
117 ret.setX(mag * cos(theta));
118 ret.setY(mag * sin(theta));