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Diffstat (limited to 'src/declarative/graphicsitems/qdeclarativepath.cpp')
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diff --git a/src/declarative/graphicsitems/qdeclarativepath.cpp b/src/declarative/graphicsitems/qdeclarativepath.cpp new file mode 100644 index 0000000000..48f112a7ca --- /dev/null +++ b/src/declarative/graphicsitems/qdeclarativepath.cpp @@ -0,0 +1,849 @@ +/**************************************************************************** +** +** Copyright (C) 2010 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 "qdeclarativepath_p.h" +#include "qdeclarativepath_p_p.h" + +#include <qfxperf_p_p.h> + +#include <QSet> + +#include <private/qbezier_p.h> + +QT_BEGIN_NAMESPACE + +/*! + \qmlclass PathElement QDeclarativePathElement + \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 +*/ + +/*! + \internal + \class QDeclarativePathElement + \ingroup group_utility +*/ + +/*! + \qmlclass Path QDeclarativePath + \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 +*/ + +/*! + \internal + \class QDeclarativePath + \ingroup group_utility + \brief The QDeclarativePath class defines a path. + \sa QDeclarativePathView +*/ +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); + d->startX = x; +} + +qreal QDeclarativePath::startY() const +{ + Q_D(const QDeclarativePath); + return d->startY; +} + +void QDeclarativePath::setStartY(qreal y) +{ + Q_D(QDeclarativePath); + d->startY = y; +} + +/*! + \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<PathElement> Path::pathElements + This property holds the objects composing the path. + + \default + + A path can contain the following path objects: + \list + \i \l PathLine - a straight line to a given position. + \i \l PathQuad - a quadratic Bezier curve to a given position with a control point. + \i \l PathCubic - a cubic Bezier curve to a given position with two control points. + \i \l PathAttribute - an attribute at a given position in the path. + \i \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<QDeclarativePathElement> QDeclarativePath::pathElements() +{ + Q_D(QDeclarativePath); + return QDeclarativeListProperty<QDeclarativePathElement>(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); + + 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<QDeclarativeCurve *>(pathElement)) { + curve->addToPath(d->_path); + AttributePoint p; + p.origpercent = d->_path.length(); + d->_attributePoints << p; + lastCurve = curve; + } else if (QDeclarativePathAttribute *attribute = qobject_cast<QDeclarativePathAttribute *>(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<QDeclarativePathPercent *>(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::componentComplete() +{ + Q_D(QDeclarativePath); + QSet<QString> attrs; + // First gather up all the attributes + foreach (QDeclarativePathElement *pathElement, d->_pathElements) { + if (QDeclarativePathAttribute *attribute = + qobject_cast<QDeclarativePathAttribute *>(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); + return d->_attributes; +} +#include <QTime> + +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); +#ifdef Q_ENABLE_PERFORMANCE_LOG + QDeclarativePerfTimer<QDeclarativePerf::QDeclarativePathViewPathCache> pc; +#endif + qreal pathLength = d->_path.length(); + const int points = int(pathLength*2); + 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(); + } + 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 changed(); + } +} + +qreal QDeclarativeCurve::y() const +{ + return _y; +} + +void QDeclarativeCurve::setY(qreal y) +{ + if (_y != y) { + _y = y; + emit changed(); + } +} + +/****************************************************************************/ + +/*! + \qmlclass PathAttribute QDeclarativePathAttribute + \since 4.7 + \brief The PathAttribute allows setting an attribute at a given position in a Path. + + The PathAttribute object allows attibutes consisting of a name and + a value to be specified for the endpoints of path segments. The + attributes are exposed to the delegate as + \l{qdeclarativeintroduction.html#attached-properties} {Attached Properties}. + The value of an attribute at any particular point is interpolated + from the PathAttributes bounding the 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.scale and + PathView.opacity attached properties to set the scale and opacity + of the delegate. + + \table + \row + \o \image declarative-pathattribute.png + \o + \snippet doc/src/snippets/declarative/pathview/pathattributes.qml 0 + \endtable + + \sa Path +*/ + +/*! + \internal + \class QDeclarativePathAttribute + \ingroup group_utility + \brief The QDeclarativePathAttribute class allows to set the value of an attribute at a given position in the path. + + \sa QDeclarativePath +*/ + + +/*! + \qmlproperty string PathAttribute::name + the name of the attribute to change. +*/ + +/*! + the name of the attribute to change. +*/ + +QString QDeclarativePathAttribute::name() const +{ + return _name; +} + +void QDeclarativePathAttribute::setName(const QString &name) +{ + _name = name; +} + +/*! + \qmlproperty string PathAttribute::value + the new value of the attribute. +*/ + +/*! + the new value of the attribute. +*/ +qreal QDeclarativePathAttribute::value() const +{ + return _value; +} + +void QDeclarativePathAttribute::setValue(qreal value) +{ + if (_value != value) { + _value = value; + emit changed(); + } +} + +/****************************************************************************/ + +/*! + \qmlclass PathLine QDeclarativePathLine + \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 +*/ + +/*! + \internal + \class QDeclarativePathLine + \ingroup group_utility + \brief The QDeclarativePathLine class defines a straight line. + + \sa QDeclarativePath +*/ + +/*! + \qmlproperty real PathLine::x + \qmlproperty real PathLine::y + + Defines the end point of the line. +*/ + +void QDeclarativePathLine::addToPath(QPainterPath &path) +{ + path.lineTo(x(), y()); +} + +/****************************************************************************/ + +/*! + \qmlclass PathQuad QDeclarativePathQuad + \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 + \o \image declarative-pathquad.png + \o + \qml + Path { + startX: 0; startY: 0 + PathQuad x: 200; y: 0; controlX: 100; controlY: 150 } + } + \endqml + \endtable + + \sa Path, PathCubic, PathLine +*/ + +/*! + \internal + \class QDeclarativePathQuad + \ingroup group_utility + \brief The QDeclarativePathQuad class defines a quadratic Bezier curve with a control point. + + \sa QDeclarativePath +*/ + + +/*! + \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 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 changed(); + } +} + +void QDeclarativePathQuad::addToPath(QPainterPath &path) +{ + path.quadTo(controlX(), controlY(), x(), y()); +} + +/****************************************************************************/ + +/*! + \qmlclass PathCubic QDeclarativePathCubic + \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 + \o \image declarative-pathcubic.png + \o + \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 +*/ + +/*! + \internal + \class QDeclarativePathCubic + \ingroup group_utility + \brief The QDeclarativePathCubic class defines a cubic Bezier curve with two control points. + + \sa QDeclarativePath +*/ + +/*! + \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 changed(); + } +} + +qreal QDeclarativePathCubic::control1Y() const +{ + return _control1Y; +} + +void QDeclarativePathCubic::setControl1Y(qreal y) +{ + if (_control1Y != y) { + _control1Y = y; + 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 changed(); + } +} + +qreal QDeclarativePathCubic::control2Y() const +{ + return _control2Y; +} + +void QDeclarativePathCubic::setControl2Y(qreal y) +{ + if (_control2Y != y) { + _control2Y = y; + emit changed(); + } +} + +void QDeclarativePathCubic::addToPath(QPainterPath &path) +{ + path.cubicTo(control1X(), control1Y(), control2X(), control2Y(), x(), y()); +} + +/****************************************************************************/ + +/*! + \qmlclass PathPercent QDeclarativePathPercent + \since 4.7 + \brief The PathPercent manipulates the way a path is interpreted. + + 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 + \o \image declarative-nopercent.png + \o + \qml + 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 + \o \image declarative-percent.png + \o + \qml + 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 +*/ + +/*! + \internal + \class QDeclarativePathPercent + \ingroup group_utility + \brief The QDeclarativePathPercent class manipulates the way a path is interpreted. + + QDeclarativePathPercent allows you to bunch up items (or spread out items) along various + segments of a QDeclarativePathView's path. + + \sa QDeclarativePath + +*/ + +qreal QDeclarativePathPercent::value() const +{ + return _value; +} + +void QDeclarativePathPercent::setValue(qreal value) +{ + _value = value; +} +QT_END_NAMESPACE |