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39
40#ifndef QQUICKCANVASITEM_P_H
41#define QQUICKCANVASITEM_P_H
42
43//
44// W A R N I N G
45// -------------
46//
47// This file is not part of the Qt API. It exists purely as an
48// implementation detail. This header file may change from version to
49// version without notice, or even be removed.
50//
51// We mean it.
52//
53
54#include <private/qtquickglobal_p.h>
55
56QT_REQUIRE_CONFIG(quick_canvas);
57
58#include <QtQuick/qquickitem.h>
59#include <private/qqmlrefcount_p.h>
60#include <QtCore/QThread>
61#include <QtCore/qmutex.h>
62#include <QtGui/QImage>
63
64QT_BEGIN_NAMESPACE
65
66class QQuickCanvasContext;
67
68class QQuickCanvasItemPrivate;
69class QQuickPixmap;
70
71class QQuickCanvasPixmap : public QQmlRefCount
72{
73public:
74 QQuickCanvasPixmap(const QImage& image);
75 QQuickCanvasPixmap(QQuickPixmap *pixmap);
76 ~QQuickCanvasPixmap();
77
78 QImage image();
79
80 qreal width() const;
81 qreal height() const;
82 bool isValid() const;
83 QQuickPixmap *pixmap() const { return m_pixmap;}
84
85private:
86 QQuickPixmap *m_pixmap;
87 QImage m_image;
88};
89
90class QQuickCanvasItem : public QQuickItem
91{
92 Q_OBJECT
93
94 Q_PROPERTY(bool available READ isAvailable NOTIFY availableChanged)
95 Q_PROPERTY(QString contextType READ contextType WRITE setContextType NOTIFY contextTypeChanged)
96 Q_PROPERTY(QJSValue context READ context NOTIFY contextChanged)
97 Q_PROPERTY(QSizeF canvasSize READ canvasSize WRITE setCanvasSize NOTIFY canvasSizeChanged)
98 Q_PROPERTY(QSize tileSize READ tileSize WRITE setTileSize NOTIFY tileSizeChanged)
99 Q_PROPERTY(QRectF canvasWindow READ canvasWindow WRITE setCanvasWindow NOTIFY canvasWindowChanged)
100 Q_PROPERTY(RenderTarget renderTarget READ renderTarget WRITE setRenderTarget NOTIFY renderTargetChanged)
101 Q_PROPERTY(RenderStrategy renderStrategy READ renderStrategy WRITE setRenderStrategy NOTIFY renderStrategyChanged)
102 QML_NAMED_ELEMENT(Canvas)
103
104public:
105 enum RenderTarget {
106 Image,
107 FramebufferObject
108 };
109 Q_ENUM(RenderTarget)
110
111 enum RenderStrategy {
112 Immediate,
113 Threaded,
114 Cooperative
115 };
116 Q_ENUM(RenderStrategy)
117
118 QQuickCanvasItem(QQuickItem *parent = nullptr);
119 ~QQuickCanvasItem();
120
121 bool isAvailable() const;
122
123 QString contextType() const;
124 void setContextType(const QString &contextType);
125
126 QJSValue context() const;
127
128 QSizeF canvasSize() const;
129 void setCanvasSize(const QSizeF &);
130
131 QSize tileSize() const;
132 void setTileSize(const QSize &);
133
134 QRectF canvasWindow() const;
135 void setCanvasWindow(const QRectF& rect);
136
137 RenderTarget renderTarget() const;
138 void setRenderTarget(RenderTarget target);
139
140 RenderStrategy renderStrategy() const;
141 void setRenderStrategy(RenderStrategy strategy);
142
143 QQuickCanvasContext *rawContext() const;
144
145 QImage toImage(const QRectF& rect = QRectF()) const;
146
147 Q_INVOKABLE void getContext(QQmlV4Function *args);
148
149 Q_INVOKABLE void requestAnimationFrame(QQmlV4Function *args);
150 Q_INVOKABLE void cancelRequestAnimationFrame(QQmlV4Function *args);
151
152 Q_INVOKABLE void requestPaint();
153 Q_INVOKABLE void markDirty(const QRectF& dirtyRect = QRectF());
154
155 Q_INVOKABLE bool save(const QString &filename) const;
156 Q_INVOKABLE QString toDataURL(const QString& type = QLatin1String("image/png")) const;
157 QQmlRefPointer<QQuickCanvasPixmap> loadedPixmap(const QUrl& url);
158
159 bool isTextureProvider() const override;
160 QSGTextureProvider *textureProvider() const override;
161
162Q_SIGNALS:
163 void paint(const QRect &region);
164 void painted();
165 void availableChanged();
166 void contextTypeChanged();
167 void contextChanged();
168 void canvasSizeChanged();
169 void tileSizeChanged();
170 void canvasWindowChanged();
171 void renderTargetChanged();
172 void renderStrategyChanged();
173 void imageLoaded();
174
175public Q_SLOTS:
176 void loadImage(const QUrl& url);
177 void unloadImage(const QUrl& url);
178 bool isImageLoaded(const QUrl& url) const;
179 bool isImageLoading(const QUrl& url) const;
180 bool isImageError(const QUrl& url) const;
181
182private Q_SLOTS:
183 void sceneGraphInitialized();
184 void checkAnimationCallbacks();
185 void invalidateSceneGraph();
186 void schedulePolish();
187
188protected:
189 void componentComplete() override;
190 void itemChange(QQuickItem::ItemChange, const QQuickItem::ItemChangeData &) override;
191 void updatePolish() override;
192 QSGNode *updatePaintNode(QSGNode *, UpdatePaintNodeData *) override;
193 void geometryChanged(const QRectF &newGeometry, const QRectF &oldGeometry) override;
194 void releaseResources() override;
195 bool event(QEvent *event) override;
196private:
197 Q_DECLARE_PRIVATE(QQuickCanvasItem)
198 Q_INVOKABLE void delayedCreate();
199 bool createContext(const QString &contextType);
200 void initializeContext(QQuickCanvasContext *context, const QVariantMap &args = QVariantMap());
201 static QRect tiledRect(const QRectF &window, const QSize &tileSize);
202 bool isPaintConnected();
203};
204
205class QQuickContext2DRenderThread : public QThread
206{
207 Q_OBJECT
208public:
209 QQuickContext2DRenderThread(QQmlEngine *eng);
210 ~QQuickContext2DRenderThread();
211
212 static QQuickContext2DRenderThread *instance(QQmlEngine *engine);
213
214private:
215 QQmlEngine *m_engine;
216 QObject *m_eventLoopQuitHack;
217 static QHash<QQmlEngine *,QQuickContext2DRenderThread*> renderThreads;
218 static QMutex renderThreadsMutex;
219};
220
221QT_END_NAMESPACE
222
223QML_DECLARE_TYPE(QQuickCanvasItem)
224
225#endif //QQUICKCANVASITEM_P_H
226

source code of qtdeclarative/src/quick/items/context2d/qquickcanvasitem_p.h