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39
40#include "qquickmaskextruder_p.h"
41#include <QtQml/qqml.h>
42#include <QtQml/qqmlinfo.h>
43#include <QImage>
44#include <QDebug>
45#include <QRandomGenerator>
46QT_BEGIN_NAMESPACE
47/*!
48 \qmltype MaskShape
49 \instantiates QQuickMaskExtruder
50 \inqmlmodule QtQuick.Particles
51 \inherits Shape
52 \brief For representing an image as a shape to affectors and emitters.
53 \ingroup qtquick-particles
54
55*/
56/*!
57 \qmlproperty url QtQuick.Particles::MaskShape::source
58
59 The image to use as the mask. Areas with non-zero opacity
60 will be considered inside the shape.
61*/
62
63
64QQuickMaskExtruder::QQuickMaskExtruder(QObject *parent) :
65 QQuickParticleExtruder(parent)
66 , m_lastWidth(-1)
67 , m_lastHeight(-1)
68{
69}
70
71void QQuickMaskExtruder::setSource(const QUrl &arg)
72{
73 if (m_source != arg) {
74 m_source = arg;
75
76 m_lastHeight = -1;//Trigger reset
77 m_lastWidth = -1;
78 emit sourceChanged(arg: m_source);
79 startMaskLoading();
80 }
81}
82
83void QQuickMaskExtruder::startMaskLoading()
84{
85 m_pix.clear(this);
86 if (m_source.isEmpty())
87 return;
88 m_pix.load(qmlEngine(this), m_source);
89 if (m_pix.isLoading())
90 m_pix.connectFinished(this, SLOT(finishMaskLoading()));
91 else
92 finishMaskLoading();
93}
94
95void QQuickMaskExtruder::finishMaskLoading()
96{
97 if (m_pix.isError())
98 qmlWarning(me: this) << m_pix.error();
99}
100
101QPointF QQuickMaskExtruder::extrude(const QRectF &r)
102{
103 ensureInitialized(r);
104 if (!m_mask.count() || m_img.isNull())
105 return r.topLeft();
106 const QPointF p = m_mask[QRandomGenerator::global()->bounded(highest: m_mask.count())];
107 //### Should random sub-pixel positioning be added?
108 return p + r.topLeft();
109}
110
111bool QQuickMaskExtruder::contains(const QRectF &bounds, const QPointF &point)
112{
113 ensureInitialized(r: bounds);//###Current usage patterns WILL lead to different bounds/r calls. Separate list?
114 if (m_img.isNull())
115 return false;
116
117 QPointF pt = point - bounds.topLeft();
118 QPoint p(pt.x() * m_img.width() / bounds.width(),
119 pt.y() * m_img.height() / bounds.height());
120 return m_img.rect().contains(p) && (m_img.pixel(pt: p) & 0xff000000);
121}
122
123void QQuickMaskExtruder::ensureInitialized(const QRectF &rf)
124{
125 // Convert to integer coords to avoid comparing floats and ints which would
126 // often result in rounding errors.
127 QRect r = rf.toRect();
128 if (m_lastWidth == r.width() && m_lastHeight == r.height())
129 return;//Same as before
130 if (!m_pix.isReady())
131 return;
132 m_lastWidth = r.width();
133 m_lastHeight = r.height();
134
135 m_mask.clear();
136
137 m_img = m_pix.image();
138 // Image will in all likelyhood be in this format already, so
139 // no extra memory or conversion takes place
140 if (m_img.format() != QImage::Format_ARGB32 && m_img.format() != QImage::Format_ARGB32_Premultiplied)
141 m_img = m_img.convertToFormat(f: QImage::Format_ARGB32_Premultiplied);
142
143 // resample on the fly using 16-bit
144 int sx = (m_img.width() << 16) / r.width();
145 int sy = (m_img.height() << 16) / r.height();
146 int w = r.width();
147 int h = r.height();
148 for (int y=0; y<h; ++y) {
149 const uint *sl = (const uint *) m_img.constScanLine((y * sy) >> 16);
150 for (int x=0; x<w; ++x) {
151 if (sl[(x * sx) >> 16] & 0xff000000)
152 m_mask << QPointF(x, y);
153 }
154 }
155}
156QT_END_NAMESPACE
157
158#include "moc_qquickmaskextruder_p.cpp"
159

source code of qtdeclarative/src/particles/qquickmaskextruder.cpp