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Branched from the monolithic repo, Qt master branch, at commit
896db169ea224deb96c59ce8af800d019de63f12

1 files changed, 213 insertions, 0 deletions

diff --git a/demos/embedded/lightmaps/slippymap.cpp b/demos/embedded/lightmaps/slippymap.cpp
new file mode 100644
index 0000000000..2c76f748bc
--- /dev/null
+++ b/demos/embedded/lightmaps/slippymap.cpp
@@ -0,0 +1,213 @@
+/****************************************************************************
+**
+** 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 demonstration applications 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 <math.h>
+
+#include <QtGui>
+#include <QtNetwork>
+#include "slippymap.h"
+
+#ifndef M_PI
+#define M_PI 3.14159265358979323846
+#endif
+
+uint qHash(const QPoint& p)
+{
+    return p.x() * 17 ^ p.y();
+}
+
+// tile size in pixels
+const int tdim = 256;
+
+QPointF tileForCoordinate(qreal lat, qreal lng, int zoom)
+{
+    qreal zn = static_cast<qreal>(1 << zoom);
+    qreal tx = (lng + 180.0) / 360.0;
+    qreal ty = (1.0 - log(tan(lat * M_PI / 180.0) +
+                          1.0 / cos(lat * M_PI / 180.0)) / M_PI) / 2.0;
+    return QPointF(tx * zn, ty * zn);
+}
+
+qreal longitudeFromTile(qreal tx, int zoom)
+{
+    qreal zn = static_cast<qreal>(1 << zoom);
+    qreal lat = tx / zn * 360.0 - 180.0;
+    return lat;
+}
+
+qreal latitudeFromTile(qreal ty, int zoom)
+{
+    qreal zn = static_cast<qreal>(1 << zoom);
+    qreal n = M_PI - 2 * M_PI * ty / zn;
+    qreal lng = 180.0 / M_PI * atan(0.5 * (exp(n) - exp(-n)));
+    return lng;
+}
+
+
+SlippyMap::SlippyMap(QObject *parent)
+    : QObject(parent), width(400), height(300), zoom(15),
+      latitude(59.9138204), longitude(10.7387413)
+{
+    m_emptyTile = QPixmap(tdim, tdim);
+    m_emptyTile.fill(Qt::lightGray);
+
+    QNetworkDiskCache *cache = new QNetworkDiskCache;
+    cache->setCacheDirectory(QDesktopServices::storageLocation
+                                (QDesktopServices::CacheLocation));
+    m_manager.setCache(cache);
+    connect(&m_manager, SIGNAL(finished(QNetworkReply*)),
+            this, SLOT(handleNetworkData(QNetworkReply*)));
+}
+
+void SlippyMap::invalidate()
+{
+    if (width <= 0 || height <= 0)
+        return;
+
+    QPointF ct = tileForCoordinate(latitude, longitude, zoom);
+    qreal tx = ct.x();
+    qreal ty = ct.y();
+
+    // top-left corner of the center tile
+    int xp = width / 2 - (tx - floor(tx)) * tdim;
+    int yp = height / 2 - (ty - floor(ty)) * tdim;
+
+    // first tile vertical and horizontal
+    int xa = (xp + tdim - 1) / tdim;
+    int ya = (yp + tdim - 1) / tdim;
+    int xs = static_cast<int>(tx) - xa;
+    int ys = static_cast<int>(ty) - ya;
+
+    // offset for top-left tile
+    m_offset = QPoint(xp - xa * tdim, yp - ya * tdim);
+
+    // last tile vertical and horizontal
+    int xe = static_cast<int>(tx) + (width - xp - 1) / tdim;
+    int ye = static_cast<int>(ty) + (height - yp - 1) / tdim;
+
+    // build a rect
+    m_tilesRect = QRect(xs, ys, xe - xs + 1, ye - ys + 1);
+
+    if (m_url.isEmpty())
+        download();
+
+    emit updated(QRect(0, 0, width, height));
+}
+
+void SlippyMap::render(QPainter *p, const QRect &rect)
+{
+    for (int x = 0; x <= m_tilesRect.width(); ++x)
+        for (int y = 0; y <= m_tilesRect.height(); ++y) {
+            QPoint tp(x + m_tilesRect.left(), y + m_tilesRect.top());
+            QRect box = tileRect(tp);
+            if (rect.intersects(box)) {
+                if (m_tilePixmaps.contains(tp))
+                    p->drawPixmap(box, m_tilePixmaps.value(tp));
+                else
+                    p->drawPixmap(box, m_emptyTile);
+            }
+        }
+}
+
+void SlippyMap::pan(const QPoint &delta)
+{
+    QPointF dx = QPointF(delta) / qreal(tdim);
+    QPointF center = tileForCoordinate(latitude, longitude, zoom) - dx;
+    latitude = latitudeFromTile(center.y(), zoom);
+    longitude = longitudeFromTile(center.x(), zoom);
+    invalidate();
+}
+
+void SlippyMap::handleNetworkData(QNetworkReply *reply)
+{
+    QImage img;
+    QPoint tp = reply->request().attribute(QNetworkRequest::User).toPoint();
+    QUrl url = reply->url();
+    if (!reply->error())
+        if (!img.load(reply, 0))
+            img = QImage();
+    reply->deleteLater();
+    m_tilePixmaps[tp] = QPixmap::fromImage(img);
+    if (img.isNull())
+        m_tilePixmaps[tp] = m_emptyTile;
+    emit updated(tileRect(tp));
+
+    // purge unused spaces
+    QRect bound = m_tilesRect.adjusted(-2, -2, 2, 2);
+    foreach(QPoint tp, m_tilePixmaps.keys())
+    if (!bound.contains(tp))
+        m_tilePixmaps.remove(tp);
+
+    download();
+}
+
+void SlippyMap::download()
+{
+    QPoint grab(0, 0);
+    for (int x = 0; x <= m_tilesRect.width(); ++x)
+        for (int y = 0; y <= m_tilesRect.height(); ++y) {
+            QPoint tp = m_tilesRect.topLeft() + QPoint(x, y);
+            if (!m_tilePixmaps.contains(tp)) {
+                grab = tp;
+                break;
+            }
+        }
+    if (grab == QPoint(0, 0)) {
+        m_url = QUrl();
+        return;
+    }
+
+    QString path = "http://tile.openstreetmap.org/%1/%2/%3.png";
+    m_url = QUrl(path.arg(zoom).arg(grab.x()).arg(grab.y()));
+    QNetworkRequest request;
+    request.setUrl(m_url);
+    request.setRawHeader("User-Agent", "Nokia (Qt) Graphics Dojo 1.0");
+    request.setAttribute(QNetworkRequest::User, QVariant(grab));
+    m_manager.get(request);
+}
+
+QRect SlippyMap::tileRect(const QPoint &tp)
+{
+    QPoint t = tp - m_tilesRect.topLeft();
+    int x = t.x() * tdim + m_offset.x();
+    int y = t.y() * tdim + m_offset.y();
+    return QRect(x, y, tdim, tdim);
+}