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+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtDeclarative module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights. These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "private/qdeclarativerectangle_p.h"
+#include "private/qdeclarativerectangle_p_p.h"
+
+#include <QPainter>
+#include <QStringBuilder>
+#include <QtCore/qmath.h>
+
+QT_BEGIN_NAMESPACE
+
+/*!
+ \internal
+ \class QDeclarativePen
+ \brief The QDeclarativePen class provides a pen used for drawing rectangle borders on a QDeclarativeView.
+
+ By default, the pen is invalid and nothing is drawn. You must either set a color (then the default
+ width is 1) or a width (then the default color is black).
+
+ A width of 1 indicates is a single-pixel line on the border of the item being painted.
+
+ Example:
+ \qml
+ Rectangle {
+ border.width: 2
+ border.color: "red"
+ }
+ \endqml
+*/
+
+void QDeclarativePen::setColor(const QColor &c)
+{
+ _color = c;
+ _valid = (_color.alpha() && _width >= 1) ? true : false;
+ emit penChanged();
+}
+
+void QDeclarativePen::setWidth(int w)
+{
+ if (_width == w && _valid)
+ return;
+
+ _width = w;
+ _valid = (_color.alpha() && _width >= 1) ? true : false;
+ emit penChanged();
+}
+
+
+/*!
+ \qmlclass GradientStop QDeclarativeGradientStop
+ \ingroup qml-basic-visual-elements
+ \since 4.7
+ \brief The GradientStop item defines the color at a position in a Gradient.
+
+ \sa Gradient
+*/
+
+/*!
+ \qmlproperty real GradientStop::position
+ \qmlproperty color GradientStop::color
+
+ The position and color properties describe the color used at a given
+ position in a gradient, as represented by a gradient stop.
+
+ The default position is 0.0; the default color is black.
+
+ \sa Gradient
+*/
+
+void QDeclarativeGradientStop::updateGradient()
+{
+ if (QDeclarativeGradient *grad = qobject_cast<QDeclarativeGradient*>(parent()))
+ grad->doUpdate();
+}
+
+/*!
+ \qmlclass Gradient QDeclarativeGradient
+ \ingroup qml-basic-visual-elements
+ \since 4.7
+ \brief The Gradient item defines a gradient fill.
+
+ A gradient is defined by two or more colors, which will be blended seamlessly.
+
+ The colors are specified as a set of GradientStop child items, each of
+ which defines a position on the gradient from 0.0 to 1.0 and a color.
+ The position of each GradientStop is defined by setting its
+ \l{GradientStop::}{position} property; its color is defined using its
+ \l{GradientStop::}{color} property.
+
+ A gradient without any gradient stops is rendered as a solid white fill.
+
+ Note that this item is not a visual representation of a gradient. To display a
+ gradient, use a visual element (like \l Rectangle) which supports the use
+ of gradients.
+
+ \section1 Example Usage
+
+ \div {class="float-right"}
+ \inlineimage qml-gradient.png
+ \enddiv
+
+ The following example declares a \l Rectangle item with a gradient starting
+ with red, blending to yellow at one third of the height of the rectangle,
+ and ending with green:
+
+ \snippet doc/src/snippets/declarative/gradient.qml code
+
+ \clearfloat
+ \section1 Performance and Limitations
+
+ Calculating gradients can be computationally expensive compared to the use
+ of solid color fills or images. Consider using gradients for static items
+ in a user interface.
+
+ In Qt 4.7, only vertical, linear gradients can be applied to items. If you
+ need to apply different orientations of gradients, a combination of rotation
+ and clipping will need to be applied to the relevant items. This can
+ introduce additional performance requirements for your application.
+
+ The use of animations involving gradient stops may not give the desired
+ result. An alternative way to animate gradients is to use pre-generated
+ images or SVG drawings containing gradients.
+
+ \sa GradientStop
+*/
+
+/*!
+ \qmlproperty list<GradientStop> Gradient::stops
+ This property holds the gradient stops describing the gradient.
+
+ By default, this property contains an empty list.
+
+ To set the gradient stops, define them as children of the Gradient element.
+*/
+
+const QGradient *QDeclarativeGradient::gradient() const
+{
+ if (!m_gradient && !m_stops.isEmpty()) {
+ m_gradient = new QLinearGradient(0,0,0,1.0);
+ for (int i = 0; i < m_stops.count(); ++i) {
+ const QDeclarativeGradientStop *stop = m_stops.at(i);
+ m_gradient->setCoordinateMode(QGradient::ObjectBoundingMode);
+ m_gradient->setColorAt(stop->position(), stop->color());
+ }
+ }
+
+ return m_gradient;
+}
+
+void QDeclarativeGradient::doUpdate()
+{
+ delete m_gradient;
+ m_gradient = 0;
+ emit updated();
+}
+
+
+/*!
+ \qmlclass Rectangle QDeclarativeRectangle
+ \ingroup qml-basic-visual-elements
+ \since 4.7
+ \brief The Rectangle item provides a filled rectangle with an optional border.
+ \inherits Item
+
+ Rectangle items are used to fill areas with solid color or gradients, and are
+ often used to hold other items.
+
+ \section1 Appearance
+
+ Each Rectangle item is painted using either a solid fill color, specified using
+ the \l color property, or a gradient, defined using a Gradient element and set
+ using the \l gradient property. If both a color and a gradient are specified,
+ the gradient is used.
+
+ You can add an optional border to a rectangle with its own color and thickness
+ by settting the \l border.color and \l border.width properties.
+
+ You can also create rounded rectangles using the \l radius property. Since this
+ introduces curved edges to the corners of a rectangle, it may be appropriate to
+ set the \l smooth property to improve its appearance.
+
+ \section1 Example Usage
+
+ \div {class="float-right"}
+ \inlineimage declarative-rect.png
+ \enddiv
+
+ The following example shows the effects of some of the common properties on a
+ Rectangle item, which in this case is used to create a square:
+
+ \snippet doc/src/snippets/declarative/rectangle/rectangle.qml document
+
+ \clearfloat
+ \section1 Performance
+
+ Using the \l smooth property improves the appearance of a rounded rectangle at
+ the cost of rendering performance. You should consider unsetting this property
+ for rectangles in motion, and only set it when they are stationary.
+
+ \sa Image
+*/
+
+int QDeclarativeRectanglePrivate::doUpdateSlotIdx = -1;
+
+QDeclarativeRectangle::QDeclarativeRectangle(QDeclarativeItem *parent)
+ : QDeclarativeItem(*(new QDeclarativeRectanglePrivate), parent)
+{
+}
+
+void QDeclarativeRectangle::doUpdate()
+{
+ Q_D(QDeclarativeRectangle);
+ d->rectImage = QPixmap();
+ const int pw = d->pen && d->pen->isValid() ? d->pen->width() : 0;
+ d->setPaintMargin((pw+1)/2);
+ update();
+}
+
+/*!
+ \qmlproperty int Rectangle::border.width
+ \qmlproperty color Rectangle::border.color
+
+ The width and color used to draw the border of the rectangle.
+
+ A width of 1 creates a thin line. For no line, use a width of 0 or a transparent color.
+
+ \note The width of the rectangle's border does not affect the geometry of the
+ rectangle itself or its position relative to other items if anchors are used.
+
+ If \c border.width is an odd number, the rectangle is painted at a half-pixel offset to retain
+ border smoothness. Also, the border is rendered evenly on either side of the
+ rectangle's boundaries, and the spare pixel is rendered to the right and below the
+ rectangle (as documented for QRect rendering). This can cause unintended effects if
+ \c border.width is 1 and the rectangle is \l{Item::clip}{clipped} by a parent item:
+
+ \div {class="float-right"}
+ \inlineimage rect-border-width.png
+ \enddiv
+
+ \snippet doc/src/snippets/declarative/rectangle/rect-border-width.qml 0
+
+ \clearfloat
+ Here, the innermost rectangle's border is clipped on the bottom and right edges by its
+ parent. To avoid this, the border width can be set to two instead of one.
+*/
+QDeclarativePen *QDeclarativeRectangle::border()
+{
+ Q_D(QDeclarativeRectangle);
+ return d->getPen();
+}
+
+/*!
+ \qmlproperty Gradient Rectangle::gradient
+
+ The gradient to use to fill the rectangle.
+
+ This property allows for the construction of simple vertical gradients.
+ Other gradients may by formed by adding rotation to the rectangle.
+
+ \div {class="float-left"}
+ \inlineimage declarative-rect_gradient.png
+ \enddiv
+
+ \snippet doc/src/snippets/declarative/rectangle/rectangle-gradient.qml rectangles
+ \clearfloat
+
+ If both a gradient and a color are specified, the gradient will be used.
+
+ \sa Gradient, color
+*/
+QDeclarativeGradient *QDeclarativeRectangle::gradient() const
+{
+ Q_D(const QDeclarativeRectangle);
+ return d->gradient;
+}
+
+void QDeclarativeRectangle::setGradient(QDeclarativeGradient *gradient)
+{
+ Q_D(QDeclarativeRectangle);
+ if (d->gradient == gradient)
+ return;
+ static int updatedSignalIdx = -1;
+ if (updatedSignalIdx < 0)
+ updatedSignalIdx = QDeclarativeGradient::staticMetaObject.indexOfSignal("updated()");
+ if (d->doUpdateSlotIdx < 0)
+ d->doUpdateSlotIdx = QDeclarativeRectangle::staticMetaObject.indexOfSlot("doUpdate()");
+ if (d->gradient)
+ QMetaObject::disconnect(d->gradient, updatedSignalIdx, this, d->doUpdateSlotIdx);
+ d->gradient = gradient;
+ if (d->gradient)
+ QMetaObject::connect(d->gradient, updatedSignalIdx, this, d->doUpdateSlotIdx);
+ update();
+}
+
+
+/*!
+ \qmlproperty real Rectangle::radius
+ This property holds the corner radius used to draw a rounded rectangle.
+
+ If radius is non-zero, the rectangle will be painted as a rounded rectangle, otherwise it will be
+ painted as a normal rectangle. The same radius is used by all 4 corners; there is currently
+ no way to specify different radii for different corners.
+*/
+qreal QDeclarativeRectangle::radius() const
+{
+ Q_D(const QDeclarativeRectangle);
+ return d->radius;
+}
+
+void QDeclarativeRectangle::setRadius(qreal radius)
+{
+ Q_D(QDeclarativeRectangle);
+ if (d->radius == radius)
+ return;
+
+ d->radius = radius;
+ d->rectImage = QPixmap();
+ update();
+ emit radiusChanged();
+}
+
+/*!
+ \qmlproperty color Rectangle::color
+ This property holds the color used to fill the rectangle.
+
+ The default color is white.
+
+ \div {class="float-right"}
+ \inlineimage rect-color.png
+ \enddiv
+
+ The following example shows rectangles with colors specified
+ using hexadecimal and named color notation:
+
+ \snippet doc/src/snippets/declarative/rectangle/rectangle-colors.qml rectangles
+
+ \clearfloat
+ If both a gradient and a color are specified, the gradient will be used.
+
+ \sa gradient
+*/
+QColor QDeclarativeRectangle::color() const
+{
+ Q_D(const QDeclarativeRectangle);
+ return d->color;
+}
+
+void QDeclarativeRectangle::setColor(const QColor &c)
+{
+ Q_D(QDeclarativeRectangle);
+ if (d->color == c)
+ return;
+
+ d->color = c;
+ d->rectImage = QPixmap();
+ update();
+ emit colorChanged();
+}
+
+void QDeclarativeRectangle::generateRoundedRect()
+{
+ Q_D(QDeclarativeRectangle);
+ if (d->rectImage.isNull()) {
+ const int pw = d->pen && d->pen->isValid() ? d->pen->width() : 0;
+ const int radius = qCeil(d->radius); //ensure odd numbered width/height so we get 1-pixel center
+
+ QString key = QLatin1String("q_") % QString::number(pw) % d->color.name() % QString::number(d->color.alpha(), 16) % QLatin1Char('_') % QString::number(radius);
+ if (d->pen && d->pen->isValid())
+ key += d->pen->color().name() % QString::number(d->pen->color().alpha(), 16);
+
+ if (!QPixmapCache::find(key, &d->rectImage)) {
+ d->rectImage = QPixmap(radius*2 + 3 + pw*2, radius*2 + 3 + pw*2);
+ d->rectImage.fill(Qt::transparent);
+ QPainter p(&(d->rectImage));
+ p.setRenderHint(QPainter::Antialiasing);
+ if (d->pen && d->pen->isValid()) {
+ QPen pn(QColor(d->pen->color()), d->pen->width());
+ p.setPen(pn);
+ } else {
+ p.setPen(Qt::NoPen);
+ }
+ p.setBrush(d->color);
+ if (pw%2)
+ p.drawRoundedRect(QRectF(qreal(pw)/2+1, qreal(pw)/2+1, d->rectImage.width()-(pw+1), d->rectImage.height()-(pw+1)), d->radius, d->radius);
+ else
+ p.drawRoundedRect(QRectF(qreal(pw)/2, qreal(pw)/2, d->rectImage.width()-pw, d->rectImage.height()-pw), d->radius, d->radius);
+
+ // end painting before inserting pixmap
+ // to pixmap cache to avoid a deep copy
+ p.end();
+ QPixmapCache::insert(key, d->rectImage);
+ }
+ }
+}
+
+void QDeclarativeRectangle::generateBorderedRect()
+{
+ Q_D(QDeclarativeRectangle);
+ if (d->rectImage.isNull()) {
+ const int pw = d->pen && d->pen->isValid() ? d->pen->width() : 0;
+
+ QString key = QLatin1String("q_") % QString::number(pw) % d->color.name() % QString::number(d->color.alpha(), 16);
+ if (d->pen && d->pen->isValid())
+ key += d->pen->color().name() % QString::number(d->pen->color().alpha(), 16);
+
+ if (!QPixmapCache::find(key, &d->rectImage)) {
+ // Adding 5 here makes qDrawBorderPixmap() paint correctly with smooth: true
+ // See QTBUG-7999 and QTBUG-10765 for more details.
+ d->rectImage = QPixmap(pw*2 + 5, pw*2 + 5);
+ d->rectImage.fill(Qt::transparent);
+ QPainter p(&(d->rectImage));
+ p.setRenderHint(QPainter::Antialiasing);
+ if (d->pen && d->pen->isValid()) {
+ QPen pn(QColor(d->pen->color()), d->pen->width());
+ pn.setJoinStyle(Qt::MiterJoin);
+ p.setPen(pn);
+ } else {
+ p.setPen(Qt::NoPen);
+ }
+ p.setBrush(d->color);
+ if (pw%2)
+ p.drawRect(QRectF(qreal(pw)/2+1, qreal(pw)/2+1, d->rectImage.width()-(pw+1), d->rectImage.height()-(pw+1)));
+ else
+ p.drawRect(QRectF(qreal(pw)/2, qreal(pw)/2, d->rectImage.width()-pw, d->rectImage.height()-pw));
+
+ // end painting before inserting pixmap
+ // to pixmap cache to avoid a deep copy
+ p.end();
+ QPixmapCache::insert(key, d->rectImage);
+ }
+ }
+}
+
+void QDeclarativeRectangle::paint(QPainter *p, const QStyleOptionGraphicsItem *, QWidget *)
+{
+ Q_D(QDeclarativeRectangle);
+ if (width() <= 0 || height() <= 0)
+ return;
+ if (d->radius > 0 || (d->pen && d->pen->isValid())
+ || (d->gradient && d->gradient->gradient()) ) {
+ drawRect(*p);
+ }
+ else {
+ bool oldAA = p->testRenderHint(QPainter::Antialiasing);
+ if (d->smooth)
+ p->setRenderHints(QPainter::Antialiasing, true);
+ p->fillRect(QRectF(0, 0, width(), height()), d->color);
+ if (d->smooth)
+ p->setRenderHint(QPainter::Antialiasing, oldAA);
+ }
+}
+
+void QDeclarativeRectangle::drawRect(QPainter &p)
+{
+ Q_D(QDeclarativeRectangle);
+ if ((d->gradient && d->gradient->gradient())
+ || d->radius > width()/2 || d->radius > height()/2
+ || width() < 3 || height() < 3) {
+ // XXX This path is still slower than the image path
+ // Image path won't work for gradients or invalid radius though
+ bool oldAA = p.testRenderHint(QPainter::Antialiasing);
+ if (d->smooth)
+ p.setRenderHint(QPainter::Antialiasing);
+ if (d->pen && d->pen->isValid()) {
+ QPen pn(QColor(d->pen->color()), d->pen->width());
+ pn.setJoinStyle(Qt::MiterJoin);
+ p.setPen(pn);
+ } else {
+ p.setPen(Qt::NoPen);
+ }
+ if (d->gradient && d->gradient->gradient())
+ p.setBrush(*d->gradient->gradient());
+ else
+ p.setBrush(d->color);
+ const int pw = d->pen && d->pen->isValid() ? d->pen->width() : 0;
+ QRectF rect;
+ if (pw%2)
+ rect = QRectF(0.5, 0.5, width()-1, height()-1);
+ else
+ rect = QRectF(0, 0, width(), height());
+ qreal radius = d->radius;
+ if (radius > width()/2 || radius > height()/2)
+ radius = qMin(width()/2, height()/2);
+ if (radius > 0.)
+ p.drawRoundedRect(rect, radius, radius);
+ else
+ p.drawRect(rect);
+ if (d->smooth)
+ p.setRenderHint(QPainter::Antialiasing, oldAA);
+ } else {
+ bool oldAA = p.testRenderHint(QPainter::Antialiasing);
+ bool oldSmooth = p.testRenderHint(QPainter::SmoothPixmapTransform);
+ if (d->smooth)
+ p.setRenderHints(QPainter::Antialiasing | QPainter::SmoothPixmapTransform, d->smooth);
+
+ const int pw = d->pen && d->pen->isValid() ? (d->pen->width()+1)/2*2 : 0;
+
+ if (d->radius > 0)
+ generateRoundedRect();
+ else
+ generateBorderedRect();
+
+ int xOffset = (d->rectImage.width()-1)/2;
+ int yOffset = (d->rectImage.height()-1)/2;
+ Q_ASSERT(d->rectImage.width() == 2*xOffset + 1);
+ Q_ASSERT(d->rectImage.height() == 2*yOffset + 1);
+
+ // check whether we've eliminated the center completely
+ if (2*xOffset > width()+pw)
+ xOffset = (width()+pw)/2;
+ if (2*yOffset > height()+pw)
+ yOffset = (height()+pw)/2;
+
+ QMargins margins(xOffset, yOffset, xOffset, yOffset);
+ QTileRules rules(Qt::StretchTile, Qt::StretchTile);
+ //NOTE: even though our item may have qreal-based width and height, qDrawBorderPixmap only supports QRects
+ qDrawBorderPixmap(&p, QRect(-pw/2, -pw/2, width()+pw, height()+pw), margins, d->rectImage, d->rectImage.rect(), margins, rules);
+
+ if (d->smooth) {
+ p.setRenderHint(QPainter::Antialiasing, oldAA);
+ p.setRenderHint(QPainter::SmoothPixmapTransform, oldSmooth);
+ }
+ }
+}
+
+/*!
+ \qmlproperty bool Rectangle::smooth
+
+ Set this property if you want the item to be smoothly scaled or
+ transformed. Smooth filtering gives better visual quality, but is slower. If
+ the item is displayed at its natural size, this property has no visual or
+ performance effect.
+
+ \note Generally scaling artifacts are only visible if the item is stationary on
+ the screen. A common pattern when animating an item is to disable smooth
+ filtering at the beginning of the animation and reenable it at the conclusion.
+
+ \image rect-smooth.png
+ On this image, smooth is turned off on the top half and on on the bottom half.
+*/
+
+QRectF QDeclarativeRectangle::boundingRect() const
+{
+ Q_D(const QDeclarativeRectangle);
+ return QRectF(-d->paintmargin, -d->paintmargin, d->width()+d->paintmargin*2, d->height()+d->paintmargin*2);
+}
+
+QT_END_NAMESPACE