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/****************************************************************************
**
** Copyright (C) 2015 The Qt Company Ltd.
** Contact: http://www.qt.io/licensing/
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** You may use this file under the terms of the BSD license as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
** * Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** * Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in
** the documentation and/or other materials provided with the
** distribution.
** * Neither the name of The Qt Company Ltd nor the names of its
** contributors may be used to endorse or promote products derived
** from this software without specific prior written permission.
**
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
** $QT_END_LICENSE$
**
****************************************************************************/
#ifndef CONTEXT2D_H
#define CONTEXT2D_H
#include "domimage.h"
#include <QPainter>
#include <QPainterPath>
#include <QString>
#include <QStack>
#include <QMetaType>
#include <QTimerEvent>
// [3]
class CanvasGradient
{
public:
CanvasGradient(const QGradient &v)
: value(v) {}
CanvasGradient() {}
QGradient value;
};
// [3]
Q_DECLARE_METATYPE(CanvasGradient)
Q_DECLARE_METATYPE(CanvasGradient*)
class ImageData {
};
class QContext2DCanvas;
//! [0]
class Context2D : public QObject
{
Q_OBJECT
// compositing
Q_PROPERTY(qreal globalAlpha READ globalAlpha WRITE setGlobalAlpha)
Q_PROPERTY(QString globalCompositeOperation READ globalCompositeOperation WRITE setGlobalCompositeOperation)
Q_PROPERTY(QVariant strokeStyle READ strokeStyle WRITE setStrokeStyle)
Q_PROPERTY(QVariant fillStyle READ fillStyle WRITE setFillStyle)
// line caps/joins
Q_PROPERTY(qreal lineWidth READ lineWidth WRITE setLineWidth)
Q_PROPERTY(QString lineCap READ lineCap WRITE setLineCap)
Q_PROPERTY(QString lineJoin READ lineJoin WRITE setLineJoin)
Q_PROPERTY(qreal miterLimit READ miterLimit WRITE setMiterLimit)
// shadows
Q_PROPERTY(qreal shadowOffsetX READ shadowOffsetX WRITE setShadowOffsetX)
Q_PROPERTY(qreal shadowOffsetY READ shadowOffsetY WRITE setShadowOffsetY)
Q_PROPERTY(qreal shadowBlur READ shadowBlur WRITE setShadowBlur)
Q_PROPERTY(QString shadowColor READ shadowColor WRITE setShadowColor)
//! [0]
public:
Context2D(QObject *parent = 0);
void setSize(int width, int height);
void setSize(const QSize &size);
QSize size() const;
void clear();
void reset();
// compositing
qreal globalAlpha() const; // (default 1.0)
QString globalCompositeOperation() const; // (default over)
QVariant strokeStyle() const; // (default black)
QVariant fillStyle() const; // (default black)
void setGlobalAlpha(qreal alpha);
void setGlobalCompositeOperation(const QString &op);
void setStrokeStyle(const QVariant &style);
void setFillStyle(const QVariant &style);
// line caps/joins
qreal lineWidth() const; // (default 1)
QString lineCap() const; // "butt", "round", "square" (default "butt")
QString lineJoin() const; // "round", "bevel", "miter" (default "miter")
qreal miterLimit() const; // (default 10)
void setLineWidth(qreal w);
void setLineCap(const QString &s);
void setLineJoin(const QString &s);
void setMiterLimit(qreal m);
// shadows
qreal shadowOffsetX() const; // (default 0)
qreal shadowOffsetY() const; // (default 0)
qreal shadowBlur() const; // (default 0)
QString shadowColor() const; // (default black)
void setShadowOffsetX(qreal x);
void setShadowOffsetY(qreal y);
void setShadowBlur(qreal b);
void setShadowColor(const QString &str);
//! [1]
public slots:
void save(); // push state on state stack
void restore(); // pop state stack and restore state
void scale(qreal x, qreal y);
void rotate(qreal angle);
void translate(qreal x, qreal y);
void transform(qreal m11, qreal m12, qreal m21, qreal m22,
qreal dx, qreal dy);
void setTransform(qreal m11, qreal m12, qreal m21, qreal m22,
qreal dx, qreal dy);
CanvasGradient createLinearGradient(qreal x0, qreal y0,
qreal x1, qreal y1);
CanvasGradient createRadialGradient(qreal x0, qreal y0,
qreal r0, qreal x1,
qreal y1, qreal r1);
// rects
void clearRect(qreal x, qreal y, qreal w, qreal h);
void fillRect(qreal x, qreal y, qreal w, qreal h);
void strokeRect(qreal x, qreal y, qreal w, qreal h);
// path API
void beginPath();
void closePath();
void moveTo(qreal x, qreal y);
void lineTo(qreal x, qreal y);
void quadraticCurveTo(qreal cpx, qreal cpy, qreal x, qreal y);
void bezierCurveTo(qreal cp1x, qreal cp1y,
qreal cp2x, qreal cp2y, qreal x, qreal y);
void arcTo(qreal x1, qreal y1, qreal x2, qreal y2, qreal radius);
void rect(qreal x, qreal y, qreal w, qreal h);
void arc(qreal x, qreal y, qreal radius,
qreal startAngle, qreal endAngle,
bool anticlockwise);
void fill();
void stroke();
void clip();
bool isPointInPath(qreal x, qreal y) const;
//! [1]
// drawing images
void drawImage(DomImage *image, qreal dx, qreal dy);
void drawImage(DomImage *image, qreal dx, qreal dy,
qreal dw, qreal dh);
void drawImage(DomImage *image, qreal sx, qreal sy,
qreal sw, qreal sh, qreal dx, qreal dy,
qreal dw, qreal dh);
// pixel manipulation
ImageData getImageData(qreal sx, qreal sy, qreal sw, qreal sh);
void putImageData(ImageData image, qreal dx, qreal dy);
//! [2]
signals:
void changed(const QImage &image);
//! [2]
protected:
void timerEvent(QTimerEvent *e);
private:
void beginPainting();
const QImage &endPainting();
void scheduleChange();
int m_changeTimerId;
QImage m_image;
QPainter m_painter;
QPainterPath m_path;
enum DirtyFlag {
DirtyTransformationMatrix = 0x00001,
DirtyClippingRegion = 0x00002,
DirtyStrokeStyle = 0x00004,
DirtyFillStyle = 0x00008,
DirtyGlobalAlpha = 0x00010,
DirtyLineWidth = 0x00020,
DirtyLineCap = 0x00040,
DirtyLineJoin = 0x00080,
DirtyMiterLimit = 0x00100,
MDirtyPen = DirtyStrokeStyle
| DirtyLineWidth
| DirtyLineCap
| DirtyLineJoin
| DirtyMiterLimit,
DirtyShadowOffsetX = 0x00200,
DirtyShadowOffsetY = 0x00400,
DirtyShadowBlur = 0x00800,
DirtyShadowColor = 0x01000,
DirtyGlobalCompositeOperation = 0x2000,
DirtyFont = 0x04000,
DirtyTextAlign = 0x08000,
DirtyTextBaseline = 0x10000,
AllIsFullOfDirt = 0xfffff
};
struct State {
State() : flags(0) {}
QMatrix matrix;
QPainterPath clipPath;
QBrush strokeStyle;
QBrush fillStyle;
qreal globalAlpha;
qreal lineWidth;
Qt::PenCapStyle lineCap;
Qt::PenJoinStyle lineJoin;
qreal miterLimit;
qreal shadowOffsetX;
qreal shadowOffsetY;
qreal shadowBlur;
QColor shadowColor;
QPainter::CompositionMode globalCompositeOperation;
QFont font;
int textAlign;
int textBaseline;
int flags;
};
State m_state;
QStack<State> m_stateStack;
};
#endif
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