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Diffstat (limited to 'examples/embedded/lightmaps/slippymap.cpp')
| -rw-r--r-- | examples/embedded/lightmaps/slippymap.cpp | 213 |
1 files changed, 213 insertions, 0 deletions
diff --git a/examples/embedded/lightmaps/slippymap.cpp b/examples/embedded/lightmaps/slippymap.cpp new file mode 100644 index 0000000000..8c71f2946a --- /dev/null +++ b/examples/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. +** +** $QT_BEGIN_LICENSE:LGPL$ +** GNU Lesser General Public License Usage +** 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. +** +** 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. +** +** Other Usage +** Alternatively, this file may be used in accordance with the terms and +** conditions contained in a signed written agreement between you and Nokia. +** +** +** +** +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#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); +} |