/**************************************************************************** ** ** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies). ** Contact: http://www.qt-project.org/legal ** ** This file is part of the QtDeclarative module of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:LGPL$ ** Commercial License Usage ** Licensees holding valid commercial Qt licenses may use this file in ** accordance with the commercial license agreement provided with the ** Software or, alternatively, in accordance with the terms contained in ** a written agreement between you and Digia. For licensing terms and ** conditions see http://qt.digia.com/licensing. For further information ** use the contact form at http://qt.digia.com/contact-us. ** ** 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, Digia gives you certain additional ** rights. These rights are described in the Digia Qt LGPL Exception ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. ** ** GNU General Public License Usage ** Alternatively, this file may be used under the terms of the GNU ** General Public License version 3.0 as published by the Free Software ** Foundation and appearing in the file LICENSE.GPL included in the ** packaging of this file. Please review the following information to ** ensure the GNU General Public License version 3.0 requirements will be ** met: http://www.gnu.org/copyleft/gpl.html. ** ** ** $QT_END_LICENSE$ ** ****************************************************************************/ #include "private/qdeclarativepath_p.h" #include "private/qdeclarativepath_p_p.h" #include #include #include #include #include QT_BEGIN_NAMESPACE /*! \qmltype PathElement \instantiates QDeclarativePathElement \ingroup qml-view-elements \since 4.7 \brief PathElement is the base path type. This type is the base for all path types. It cannot be instantiated. \sa Path, PathAttribute, PathPercent, PathLine, PathQuad, PathCubic */ /*! \qmltype Path \instantiates QDeclarativePath \ingroup qml-view-elements \since 4.7 \brief A Path object defines a path for use by \l PathView. A Path is composed of one or more path segments - PathLine, PathQuad, PathCubic. The spacing of the items along the Path can be adjusted via a PathPercent object. PathAttribute allows named attributes with values to be defined along the path. \sa PathView, PathAttribute, PathPercent, PathLine, PathQuad, PathCubic */ QDeclarativePath::QDeclarativePath(QObject *parent) : QObject(*(new QDeclarativePathPrivate), parent) { } QDeclarativePath::~QDeclarativePath() { } /*! \qmlproperty real Path::startX \qmlproperty real Path::startY These properties hold the starting position of the path. */ qreal QDeclarativePath::startX() const { Q_D(const QDeclarativePath); return d->startX; } void QDeclarativePath::setStartX(qreal x) { Q_D(QDeclarativePath); if (qFuzzyCompare(x, d->startX)) return; d->startX = x; emit startXChanged(); processPath(); } qreal QDeclarativePath::startY() const { Q_D(const QDeclarativePath); return d->startY; } void QDeclarativePath::setStartY(qreal y) { Q_D(QDeclarativePath); if (qFuzzyCompare(y, d->startY)) return; d->startY = y; emit startYChanged(); processPath(); } /*! \qmlproperty bool Path::closed This property holds whether the start and end of the path are identical. */ bool QDeclarativePath::isClosed() const { Q_D(const QDeclarativePath); return d->closed; } /*! \qmlproperty list Path::pathElements This property holds the objects composing the path. \default A path can contain the following path objects: \list \li \l PathLine - a straight line to a given position. \li \l PathQuad - a quadratic Bezier curve to a given position with a control point. \li \l PathCubic - a cubic Bezier curve to a given position with two control points. \li \l PathAttribute - an attribute at a given position in the path. \li \l PathPercent - a way to spread out items along various segments of the path. \endlist \snippet doc/src/snippets/declarative/pathview/pathattributes.qml 2 */ QDeclarativeListProperty QDeclarativePath::pathElements() { Q_D(QDeclarativePath); return QDeclarativeListProperty(this, d->_pathElements); } void QDeclarativePath::interpolate(int idx, const QString &name, qreal value) { Q_D(QDeclarativePath); if (!idx) return; qreal lastValue = 0; qreal lastPercent = 0; int search = idx - 1; while(search >= 0) { const AttributePoint &point = d->_attributePoints.at(search); if (point.values.contains(name)) { lastValue = point.values.value(name); lastPercent = point.origpercent; break; } --search; } ++search; const AttributePoint &curPoint = d->_attributePoints.at(idx); for (int ii = search; ii < idx; ++ii) { AttributePoint &point = d->_attributePoints[ii]; qreal val = lastValue + (value - lastValue) * (point.origpercent - lastPercent) / (curPoint.origpercent - lastPercent); point.values.insert(name, val); } } void QDeclarativePath::endpoint(const QString &name) { Q_D(QDeclarativePath); const AttributePoint &first = d->_attributePoints.first(); qreal val = first.values.value(name); for (int ii = d->_attributePoints.count() - 1; ii >= 0; ii--) { const AttributePoint &point = d->_attributePoints.at(ii); if (point.values.contains(name)) { for (int jj = ii + 1; jj < d->_attributePoints.count(); ++jj) { AttributePoint &setPoint = d->_attributePoints[jj]; setPoint.values.insert(name, val); } return; } } } void QDeclarativePath::processPath() { Q_D(QDeclarativePath); if (!d->componentComplete) return; d->_pointCache.clear(); d->_attributePoints.clear(); d->_path = QPainterPath(); AttributePoint first; for (int ii = 0; ii < d->_attributes.count(); ++ii) first.values[d->_attributes.at(ii)] = 0; d->_attributePoints << first; d->_path.moveTo(d->startX, d->startY); QDeclarativeCurve *lastCurve = 0; foreach (QDeclarativePathElement *pathElement, d->_pathElements) { if (QDeclarativeCurve *curve = qobject_cast(pathElement)) { curve->addToPath(d->_path); AttributePoint p; p.origpercent = d->_path.length(); d->_attributePoints << p; lastCurve = curve; } else if (QDeclarativePathAttribute *attribute = qobject_cast(pathElement)) { AttributePoint &point = d->_attributePoints.last(); point.values[attribute->name()] = attribute->value(); interpolate(d->_attributePoints.count() - 1, attribute->name(), attribute->value()); } else if (QDeclarativePathPercent *percent = qobject_cast(pathElement)) { AttributePoint &point = d->_attributePoints.last(); point.values[QLatin1String("_qfx_percent")] = percent->value(); interpolate(d->_attributePoints.count() - 1, QLatin1String("_qfx_percent"), percent->value()); } } // Fixup end points const AttributePoint &last = d->_attributePoints.last(); for (int ii = 0; ii < d->_attributes.count(); ++ii) { if (!last.values.contains(d->_attributes.at(ii))) endpoint(d->_attributes.at(ii)); } // Adjust percent qreal length = d->_path.length(); qreal prevpercent = 0; qreal prevorigpercent = 0; for (int ii = 0; ii < d->_attributePoints.count(); ++ii) { const AttributePoint &point = d->_attributePoints.at(ii); if (point.values.contains(QLatin1String("_qfx_percent"))) { //special string for QDeclarativePathPercent if ( ii > 0) { qreal scale = (d->_attributePoints[ii].origpercent/length - prevorigpercent) / (point.values.value(QLatin1String("_qfx_percent"))-prevpercent); d->_attributePoints[ii].scale = scale; } d->_attributePoints[ii].origpercent /= length; d->_attributePoints[ii].percent = point.values.value(QLatin1String("_qfx_percent")); prevorigpercent = d->_attributePoints[ii].origpercent; prevpercent = d->_attributePoints[ii].percent; } else { d->_attributePoints[ii].origpercent /= length; d->_attributePoints[ii].percent = d->_attributePoints[ii].origpercent; } } d->closed = lastCurve && d->startX == lastCurve->x() && d->startY == lastCurve->y(); emit changed(); } void QDeclarativePath::classBegin() { Q_D(QDeclarativePath); d->componentComplete = false; } void QDeclarativePath::componentComplete() { Q_D(QDeclarativePath); QSet attrs; d->componentComplete = true; // First gather up all the attributes foreach (QDeclarativePathElement *pathElement, d->_pathElements) { if (QDeclarativePathAttribute *attribute = qobject_cast(pathElement)) attrs.insert(attribute->name()); } d->_attributes = attrs.toList(); processPath(); foreach (QDeclarativePathElement *pathElement, d->_pathElements) connect(pathElement, SIGNAL(changed()), this, SLOT(processPath())); } QPainterPath QDeclarativePath::path() const { Q_D(const QDeclarativePath); return d->_path; } QStringList QDeclarativePath::attributes() const { Q_D(const QDeclarativePath); if (!d->componentComplete) { QSet attrs; // First gather up all the attributes foreach (QDeclarativePathElement *pathElement, d->_pathElements) { if (QDeclarativePathAttribute *attribute = qobject_cast(pathElement)) attrs.insert(attribute->name()); } return attrs.toList(); } return d->_attributes; } static inline QBezier nextBezier(const QPainterPath &path, int *from, qreal *bezLength) { const int lastElement = path.elementCount() - 1; for (int i=*from; i <= lastElement; ++i) { const QPainterPath::Element &e = path.elementAt(i); switch (e.type) { case QPainterPath::MoveToElement: break; case QPainterPath::LineToElement: { QLineF line(path.elementAt(i-1), e); *bezLength = line.length(); QPointF a = path.elementAt(i-1); QPointF delta = e - a; *from = i+1; return QBezier::fromPoints(a, a + delta / 3, a + 2 * delta / 3, e); } case QPainterPath::CurveToElement: { QBezier b = QBezier::fromPoints(path.elementAt(i-1), e, path.elementAt(i+1), path.elementAt(i+2)); *bezLength = b.length(); *from = i+3; return b; } default: break; } } *from = lastElement; *bezLength = 0; return QBezier(); } void QDeclarativePath::createPointCache() const { Q_D(const QDeclarativePath); qreal pathLength = d->_path.length(); if (pathLength <= 0 || qIsNaN(pathLength)) return; // more points means less jitter between items as they move along the // path, but takes longer to generate const int points = qCeil(pathLength*5); const int lastElement = d->_path.elementCount() - 1; d->_pointCache.resize(points+1); int currElement = 0; qreal bezLength = 0; QBezier currBez = nextBezier(d->_path, &currElement, &bezLength); qreal currLength = bezLength; qreal epc = currLength / pathLength; for (int i = 0; i < d->_pointCache.size(); i++) { //find which set we are in qreal prevPercent = 0; qreal prevOrigPercent = 0; for (int ii = 0; ii < d->_attributePoints.count(); ++ii) { qreal percent = qreal(i)/points; const AttributePoint &point = d->_attributePoints.at(ii); if (percent < point.percent || ii == d->_attributePoints.count() - 1) { //### || is special case for very last item qreal elementPercent = (percent - prevPercent); qreal spc = prevOrigPercent + elementPercent * point.scale; while (spc > epc) { if (currElement > lastElement) break; currBez = nextBezier(d->_path, &currElement, &bezLength); if (bezLength == 0.0) { currLength = pathLength; epc = 1.0; break; } currLength += bezLength; epc = currLength / pathLength; } qreal realT = (pathLength * spc - (currLength - bezLength)) / bezLength; d->_pointCache[i] = currBez.pointAt(qBound(qreal(0), realT, qreal(1))); break; } prevOrigPercent = point.origpercent; prevPercent = point.percent; } } } QPointF QDeclarativePath::pointAt(qreal p) const { Q_D(const QDeclarativePath); if (d->_pointCache.isEmpty()) { createPointCache(); if (d->_pointCache.isEmpty()) return QPointF(); } int idx = qRound(p*d->_pointCache.size()); if (idx >= d->_pointCache.size()) idx = d->_pointCache.size() - 1; else if (idx < 0) idx = 0; return d->_pointCache.at(idx); } qreal QDeclarativePath::attributeAt(const QString &name, qreal percent) const { Q_D(const QDeclarativePath); if (percent < 0 || percent > 1) return 0; for (int ii = 0; ii < d->_attributePoints.count(); ++ii) { const AttributePoint &point = d->_attributePoints.at(ii); if (point.percent == percent) { return point.values.value(name); } else if (point.percent > percent) { qreal lastValue = ii?(d->_attributePoints.at(ii - 1).values.value(name)):0; qreal lastPercent = ii?(d->_attributePoints.at(ii - 1).percent):0; qreal curValue = point.values.value(name); qreal curPercent = point.percent; return lastValue + (curValue - lastValue) * (percent - lastPercent) / (curPercent - lastPercent); } } return 0; } /****************************************************************************/ qreal QDeclarativeCurve::x() const { return _x; } void QDeclarativeCurve::setX(qreal x) { if (_x != x) { _x = x; emit xChanged(); emit changed(); } } qreal QDeclarativeCurve::y() const { return _y; } void QDeclarativeCurve::setY(qreal y) { if (_y != y) { _y = y; emit yChanged(); emit changed(); } } /****************************************************************************/ /*! \qmltype PathAttribute \instantiates QDeclarativePathAttribute \ingroup qml-view-elements \since 4.7 \brief The PathAttribute allows setting an attribute at a given position in a Path. The PathAttribute object allows attributes consisting of a name and a value to be specified for various points along a path. The attributes are exposed to the delegate as \l{qdeclarativeintroduction.html#attached-properties} {Attached Properties}. The value of an attribute at any particular point along the path is interpolated from the PathAttributes bounding that point. The example below shows a path with the items scaled to 30% with opacity 50% at the top of the path and scaled 100% with opacity 100% at the bottom. Note the use of the PathView.iconScale and PathView.iconOpacity attached properties to set the scale and opacity of the delegate. \table \row \li \image declarative-pathattribute.png \li \snippet doc/src/snippets/declarative/pathview/pathattributes.qml 0 (see the PathView documentation for the specification of ContactModel.qml used for ContactModel above.) \endtable \sa Path */ /*! \qmlproperty string PathAttribute::name This property holds the name of the attribute to change. This attribute will be available to the delegate as PathView. Note that using an existing Item property name such as "opacity" as an attribute is allowed. This is because path attributes add a new \l{qdeclarativeintroduction.html#attached-properties} {Attached Property} which in no way clashes with existing properties. */ /*! the name of the attribute to change. */ QString QDeclarativePathAttribute::name() const { return _name; } void QDeclarativePathAttribute::setName(const QString &name) { if (_name == name) return; _name = name; emit nameChanged(); } /*! \qmlproperty real PathAttribute::value This property holds the value for the attribute. The value specified can be used to influence the visual appearance of an item along the path. For example, the following Path specifies an attribute named \e itemRotation, which has the value \e 0 at the beginning of the path, and the value 90 at the end of the path. \qml Path { startX: 0 startY: 0 PathAttribute { name: "itemRotation"; value: 0 } PathLine { x: 100; y: 100 } PathAttribute { name: "itemRotation"; value: 90 } } \endqml In our delegate, we can then bind the \e rotation property to the \l{qdeclarativeintroduction.html#attached-properties} {Attached Property} \e PathView.itemRotation created for this attribute. \qml Rectangle { width: 10; height: 10 rotation: PathView.itemRotation } \endqml As each item is positioned along the path, it will be rotated accordingly: an item at the beginning of the path with be not be rotated, an item at the end of the path will be rotated 90 degrees, and an item mid-way along the path will be rotated 45 degrees. */ /*! the new value of the attribute. */ qreal QDeclarativePathAttribute::value() const { return _value; } void QDeclarativePathAttribute::setValue(qreal value) { if (_value != value) { _value = value; emit valueChanged(); emit changed(); } } /****************************************************************************/ /*! \qmltype PathLine \instantiates QDeclarativePathLine \ingroup qml-view-elements \since 4.7 \brief The PathLine defines a straight line. The example below creates a path consisting of a straight line from 0,100 to 200,100: \qml Path { startX: 0; startY: 100 PathLine { x: 200; y: 100 } } \endqml \sa Path, PathQuad, PathCubic */ /*! \qmlproperty real PathLine::x \qmlproperty real PathLine::y Defines the end point of the line. */ void QDeclarativePathLine::addToPath(QPainterPath &path) { path.lineTo(x(), y()); } /****************************************************************************/ /*! \qmltype PathQuad \instantiates QDeclarativePathQuad \ingroup qml-view-elements \since 4.7 \brief The PathQuad defines a quadratic Bezier curve with a control point. The following QML produces the path shown below: \table \row \li \image declarative-pathquad.png \li \qml Path { startX: 0; startY: 0 PathQuad { x: 200; y: 0; controlX: 100; controlY: 150 } } \endqml \endtable \sa Path, PathCubic, PathLine */ /*! \qmlproperty real PathQuad::x \qmlproperty real PathQuad::y Defines the end point of the curve. */ /*! \qmlproperty real PathQuad::controlX \qmlproperty real PathQuad::controlY Defines the position of the control point. */ /*! the x position of the control point. */ qreal QDeclarativePathQuad::controlX() const { return _controlX; } void QDeclarativePathQuad::setControlX(qreal x) { if (_controlX != x) { _controlX = x; emit controlXChanged(); emit changed(); } } /*! the y position of the control point. */ qreal QDeclarativePathQuad::controlY() const { return _controlY; } void QDeclarativePathQuad::setControlY(qreal y) { if (_controlY != y) { _controlY = y; emit controlYChanged(); emit changed(); } } void QDeclarativePathQuad::addToPath(QPainterPath &path) { path.quadTo(controlX(), controlY(), x(), y()); } /****************************************************************************/ /*! \qmltype PathCubic \instantiates QDeclarativePathCubic \ingroup qml-view-elements \since 4.7 \brief The PathCubic defines a cubic Bezier curve with two control points. The following QML produces the path shown below: \table \row \li \image declarative-pathcubic.png \li \qml Path { startX: 20; startY: 0 PathCubic { x: 180; y: 0 control1X: -10; control1Y: 90 control2X: 210; control2Y: 90 } } \endqml \endtable \sa Path, PathQuad, PathLine */ /*! \qmlproperty real PathCubic::x \qmlproperty real PathCubic::y Defines the end point of the curve. */ /*! \qmlproperty real PathCubic::control1X \qmlproperty real PathCubic::control1Y Defines the position of the first control point. */ qreal QDeclarativePathCubic::control1X() const { return _control1X; } void QDeclarativePathCubic::setControl1X(qreal x) { if (_control1X != x) { _control1X = x; emit control1XChanged(); emit changed(); } } qreal QDeclarativePathCubic::control1Y() const { return _control1Y; } void QDeclarativePathCubic::setControl1Y(qreal y) { if (_control1Y != y) { _control1Y = y; emit control1YChanged(); emit changed(); } } /*! \qmlproperty real PathCubic::control2X \qmlproperty real PathCubic::control2Y Defines the position of the second control point. */ qreal QDeclarativePathCubic::control2X() const { return _control2X; } void QDeclarativePathCubic::setControl2X(qreal x) { if (_control2X != x) { _control2X = x; emit control2XChanged(); emit changed(); } } qreal QDeclarativePathCubic::control2Y() const { return _control2Y; } void QDeclarativePathCubic::setControl2Y(qreal y) { if (_control2Y != y) { _control2Y = y; emit control2YChanged(); emit changed(); } } void QDeclarativePathCubic::addToPath(QPainterPath &path) { path.cubicTo(control1X(), control1Y(), control2X(), control2Y(), x(), y()); } /****************************************************************************/ /*! \qmltype PathPercent \instantiates QDeclarativePathPercent \ingroup qml-view-elements \since 4.7 \brief The PathPercent manipulates the way a path is interpreted. PathPercent allows you to manipulate the spacing between items on a PathView's path. You can use it to bunch together items on part of the path, and spread them out on other parts of the path. The examples below show the normal distrubution of items along a path compared to a distribution which places 50% of the items along the PathLine section of the path. \table \row \li \image declarative-nopercent.png \li \qml PathView { // ... Path { startX: 20; startY: 0 PathQuad { x: 50; y: 80; controlX: 0; controlY: 80 } PathLine { x: 150; y: 80 } PathQuad { x: 180; y: 0; controlX: 200; controlY: 80 } } } \endqml \row \li \image declarative-percent.png \li \qml PathView { // ... Path { startX: 20; startY: 0 PathQuad { x: 50; y: 80; controlX: 0; controlY: 80 } PathPercent { value: 0.25 } PathLine { x: 150; y: 80 } PathPercent { value: 0.75 } PathQuad { x: 180; y: 0; controlX: 200; controlY: 80 } PathPercent { value: 1 } } } \endqml \endtable \sa Path */ /*! \qmlproperty real PathPercent::value The proporation of items that should be laid out up to this point. This value should always be higher than the last value specified by a PathPercent at a previous position in the Path. In the following example we have a Path made up of three PathLines. Normally, the items of the PathView would be laid out equally along this path, with an equal number of items per line segment. PathPercent allows us to specify that the first and third lines should each hold 10% of the laid out items, while the second line should hold the remaining 80%. \qml PathView { // ... Path { startX: 0; startY: 0 PathLine { x:100; y: 0; } PathPercent { value: 0.1 } PathLine { x: 100; y: 100 } PathPercent { value: 0.9 } PathLine { x: 100; y: 0 } PathPercent { value: 1 } } } \endqml */ qreal QDeclarativePathPercent::value() const { return _value; } void QDeclarativePathPercent::setValue(qreal value) { if (_value != value) { _value = value; emit valueChanged(); emit changed(); } } QT_END_NAMESPACE