1 files changed, 199 insertions, 0 deletions
diff --git a/examples/webkitwidgets/scroller/plot/plotwidget.cpp b/examples/webkitwidgets/scroller/plot/plotwidget.cpp
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+++ b/examples/webkitwidgets/scroller/plot/plotwidget.cpp
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+/****************************************************************************
+**
+** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** 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 Digia Plc and its Subsidiary(-ies) 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."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QPushButton>
+#include <QTextStream>
+#include <QColor>
+#include <QPainter>
+#include <QLabel>
+#include <QResizeEvent>
+#include <QAbstractScrollArea>
+
+#include "plotwidget.h"
+#include "qscroller.h"
+
+PlotWidget::PlotWidget(bool /*smallscreen*/)
+    : QWidget(), m_widget(0)
+{
+    setWindowTitle(QLatin1String("Plot"));
+    m_clear = new QPushButton(QLatin1String("Clear"), this);
+    connect(m_clear, SIGNAL(clicked()), this, SLOT(reset()));
+    m_legend = new QLabel(this);
+    QString legend;
+    QTextStream ts(&legend);
+    // ok. this wouldn't pass the w3c html verification...
+    ts << "<table style=\"color:#000;\" border=\"0\">";
+    ts << "<tr><td width=\"30\" bgcolor=\"" << QColor(Qt::red).light().name() << "\" /><td>Velocity X</td></tr>";
+    ts << "<tr><td width=\"30\" bgcolor=\"" << QColor(Qt::red).dark().name() << "\" /><td>Velocity Y</td></tr>";
+    ts << "<tr><td width=\"30\" bgcolor=\"" << QColor(Qt::green).light().name() << "\" /><td>Content Position X</td></tr>";
+    ts << "<tr><td width=\"30\" bgcolor=\"" << QColor(Qt::green).dark().name() << "\" /><td>Content Position Y</td></tr>";
+    ts << "<tr><td width=\"30\" bgcolor=\"" << QColor(Qt::blue).light().name() << "\" /><td>Overshoot Position X</td></tr>";
+    ts << "<tr><td width=\"30\" bgcolor=\"" << QColor(Qt::blue).dark().name() << "\" /><td>Overshoot Position Y</td></tr>";
+    ts << "</table>";
+    m_legend->setText(legend);
+}
+
+void PlotWidget::setScroller(QWidget *widget)
+{
+    if (QAbstractScrollArea *area = qobject_cast<QAbstractScrollArea *>(widget))
+        widget = area->viewport();
+
+    if (m_widget)
+        m_widget->removeEventFilter(this);
+    m_widget = widget;
+    reset();
+    if (m_widget)
+        m_widget->installEventFilter(this);
+}
+
+bool PlotWidget::eventFilter(QObject *obj, QEvent *ev)
+{
+    if (ev->type() == QEvent::Scroll) {
+        QScrollEvent *se = static_cast<QScrollEvent *>(ev);
+        QScroller *scroller = QScroller::scroller(m_widget);
+
+        QPointF v = scroller->velocity();
+        //v.rx() *= scroller->pixelPerMeter().x();
+        //v.ry() *= scroller->pixelPerMeter().y();
+
+        PlotItem pi = { v, se->contentPos(), se->overshootDistance() };
+        addPlotItem(pi);
+    }
+
+    return QWidget::eventFilter(obj, ev);
+}
+
+static inline void doMaxMin(const QPointF &v, qreal &minmaxv)
+{
+    minmaxv = qMax(minmaxv, qMax(qAbs(v.x()), qAbs(v.y())));
+}
+
+void PlotWidget::addPlotItem(const PlotItem &pi)
+{
+    m_plotitems.append(pi);
+    minMaxVelocity = minMaxPosition = 0;
+
+    while (m_plotitems.size() > 500)
+        m_plotitems.removeFirst();
+
+    foreach (const PlotItem &pi, m_plotitems) {
+        doMaxMin(pi.velocity, minMaxVelocity);
+        doMaxMin(pi.contentPosition, minMaxPosition);
+        doMaxMin(pi.overshootPosition, minMaxPosition);
+    }
+    update();
+}
+
+void PlotWidget::reset()
+{
+    m_plotitems.clear();
+    minMaxVelocity = minMaxPosition = 0;
+    update();
+}
+
+void PlotWidget::resizeEvent(QResizeEvent *)
+{
+    QSize cs = m_clear->sizeHint();
+    QSize ls = m_legend->sizeHint();
+    m_clear->setGeometry(4, 4, cs.width(), cs.height());
+    m_legend->setGeometry(4, height() - ls.height() - 4, ls.width(), ls.height());
+}
+
+void PlotWidget::paintEvent(QPaintEvent *)
+{
+#define SCALE(v, mm)  ((qreal(1) - (v / mm)) * qreal(0.5) * height())
+
+    QColor rvColor = Qt::red;
+    QColor cpColor = Qt::green;
+    QColor opColor = Qt::blue;
+
+
+    QPainter p(this);
+    //p.setRenderHints(QPainter::Antialiasing); //too slow for 60fps
+    p.fillRect(rect(), Qt::white);
+
+    p.setPen(Qt::black);
+    p.drawLine(0, SCALE(0, 1), width(), SCALE(0, 1));
+
+    if (m_plotitems.isEmpty())
+        return;
+
+    int x = 2;
+    int offset = m_plotitems.size() - width() / 2;
+    QList<PlotItem>::const_iterator it = m_plotitems.constBegin();
+    if (offset > 0)
+        it += (offset - 1);
+
+    const PlotItem *last = &(*it++);
+
+    while (it != m_plotitems.constEnd()) {
+        p.setPen(rvColor.light());
+        p.drawLine(qreal(x - 2), SCALE(last->velocity.x(), minMaxVelocity),
+                   qreal(x), SCALE(it->velocity.x(), minMaxVelocity));
+        p.setPen(rvColor.dark());
+        p.drawLine(qreal(x - 2), SCALE(last->velocity.y(), minMaxVelocity),
+                   qreal(x), SCALE(it->velocity.y(), minMaxVelocity));
+
+        p.setPen(cpColor.light());
+        p.drawLine(qreal(x - 2), SCALE(last->contentPosition.x(), minMaxPosition),
+                   qreal(x), SCALE(it->contentPosition.x(), minMaxPosition));
+        p.setPen(cpColor.dark());
+        p.drawLine(qreal(x - 2), SCALE(last->contentPosition.y(), minMaxPosition),
+                   qreal(x), SCALE(it->contentPosition.y(), minMaxPosition));
+
+        p.setPen(opColor.light());
+        p.drawLine(qreal(x - 2), SCALE(last->overshootPosition.x(), minMaxPosition),
+                   qreal(x), SCALE(it->overshootPosition.x(), minMaxPosition));
+        p.setPen(opColor.dark());
+        p.drawLine(qreal(x - 2), SCALE(last->overshootPosition.y(), minMaxPosition),
+                   qreal(x), SCALE(it->overshootPosition.y(), minMaxPosition));
+
+        last = &(*it++);
+        x += 2;
+    }
+
+    QString toptext = QString("%1 [m/s] / %2 [pix]").arg(minMaxVelocity, 0, 'f', 2).arg(minMaxPosition, 0, 'f', 2);
+    QString bottomtext = QString("-%1 [m/s] / -%2 [pix]").arg(minMaxVelocity, 0, 'f', 2).arg(minMaxPosition, 0, 'f', 2);
+
+    p.setPen(Qt::black);
+    p.drawText(rect(), Qt::AlignTop | Qt::AlignHCenter, toptext);
+    p.drawText(rect(), Qt::AlignBottom | Qt::AlignHCenter, bottomtext);
+#undef SCALE
+}