Fixed error in Cessna model.

src/ui/map3D/Imagery.cc

+/*=====================================================================
+
+QGroundControl Open Source Ground Control Station
+
+(c) 2009, 2010 QGROUNDCONTROL PROJECT <http://www.qgroundcontrol.org>
+
+This file is part of the QGROUNDCONTROL project
+
+    QGROUNDCONTROL is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    QGROUNDCONTROL is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with QGROUNDCONTROL. If not, see <http://www.gnu.org/licenses/>.
+
+======================================================================*/
+
+/**
+ * @file
+ *   @brief Definition of the class Imagery.
+ *
+ *   @author Lionel Heng <hengli@student.ethz.ch>
+ *
+ */
+
+#include "Imagery.h"
+
+#include <cmath>
+#include <iomanip>
+#include <sstream>
+
+const double WGS84_A = 6378137.0;
+const double WGS84_ECCSQ = 0.00669437999013;
+
+const int32_t MAX_ZOOM_LEVEL = 20;
+
+Imagery::Imagery()
+    : textureCache(new TextureCache(1000))
+{
+
+}
+
+void
+Imagery::setImageryType(ImageryType type)
+{
+    currentImageryType = type;
+}
+
+void
+Imagery::setOffset(double xOffset, double yOffset)
+{
+    this->xOffset = xOffset;
+    this->yOffset = yOffset;
+}
+
+void
+Imagery::prefetch2D(double windowWidth, double windowHeight,
+                    double zoom, double xOrigin, double yOrigin,
+                    double viewXOffset, double viewYOffset,
+                    const QString& utmZone)
+{
+    double tileResolution;
+    if (currentImageryType == GOOGLE_SATELLITE ||
+        currentImageryType == GOOGLE_MAP)
+    {
+        tileResolution = 1.0;
+        while (tileResolution * 3.0 / 2.0 < 1.0 / zoom)
+        {
+            tileResolution *= 2.0;
+        }
+        if (tileResolution > 512.0)
+        {
+            tileResolution = 512.0;
+        }
+    }
+    else if (currentImageryType == SWISSTOPO_SATELLITE)
+    {
+        tileResolution = 0.25;
+    }
+
+    int32_t minTileX, minTileY, maxTileX, maxTileY;
+    int32_t zoomLevel;
+
+    tileBounds(tileResolution,
+               xOrigin + viewXOffset - windowWidth / 2.0 / zoom,
+               yOrigin + viewYOffset - windowHeight / 2.0 / zoom,
+               xOrigin + viewXOffset + windowWidth / 2.0 / zoom,
+               yOrigin + viewYOffset + windowHeight / 2.0 / zoom, utmZone,
+               minTileX, minTileY, maxTileX, maxTileY, zoomLevel);
+
+    for (int32_t r = minTileY; r <= maxTileY; ++r)
+    {
+        for (int32_t c = minTileX; c <= maxTileX; ++c)
+        {
+            QString url = getTileLocation(c, r, zoomLevel, tileResolution);
+
+            TexturePtr t = textureCache->get(url);
+        }
+    }
+}
+
+void
+Imagery::draw2D(double windowWidth, double windowHeight,
+                double zoom, double xOrigin, double yOrigin,
+                double viewXOffset, double viewYOffset,
+                const QString& utmZone)
+{
+    double tileResolution;
+    if (currentImageryType == GOOGLE_SATELLITE ||
+        currentImageryType == GOOGLE_MAP)
+    {
+        tileResolution = 1.0;
+        while (tileResolution * 3.0 / 2.0 < 1.0 / zoom)
+        {
+            tileResolution *= 2.0;
+        }
+        if (tileResolution > 512.0)
+        {
+            tileResolution = 512.0;
+        }
+    }
+    else if (currentImageryType == SWISSTOPO_SATELLITE)
+    {
+        tileResolution = 0.25;
+    }
+
+    int32_t minTileX, minTileY, maxTileX, maxTileY;
+    int32_t zoomLevel;
+
+    tileBounds(tileResolution,
+               xOrigin + viewXOffset - windowWidth / 2.0 / zoom * 1.5,
+               yOrigin + viewYOffset - windowHeight / 2.0 / zoom * 1.5,
+               xOrigin + viewXOffset + windowWidth / 2.0 / zoom * 1.5,
+               yOrigin + viewYOffset + windowHeight / 2.0 / zoom * 1.5, utmZone,
+               minTileX, minTileY, maxTileX, maxTileY, zoomLevel);
+
+    for (int32_t r = minTileY; r <= maxTileY; ++r)
+    {
+        for (int32_t c = minTileX; c <= maxTileX; ++c)
+        {
+            QString tileURL = getTileLocation(c, r, zoomLevel, tileResolution);
+
+            double x1, y1, x2, y2, x3, y3, x4, y4;
+            imageBounds(c, r, tileResolution, x1, y1, x2, y2, x3, y3, x4, y4);
+
+            TexturePtr t = textureCache->get(tileURL);
+            if (!t.isNull())
+            {
+                t->draw(x1 - xOrigin, y1 - yOrigin,
+                        x2 - xOrigin, y2 - yOrigin,
+                        x3 - xOrigin, y3 - yOrigin,
+                        x4 - xOrigin, y4 - yOrigin, true);
+            }
+        }
+    }
+}
+
+void
+Imagery::prefetch3D(double radius, double tileResolution,
+                    double xOrigin, double yOrigin,
+                    double viewXOffset, double viewYOffset,
+                    const QString& utmZone, bool useHeightModel)
+{
+    int32_t minTileX, minTileY, maxTileX, maxTileY;
+    int32_t zoomLevel;
+
+    tileBounds(tileResolution,
+               xOrigin + viewXOffset - radius,
+               yOrigin + viewYOffset - radius,
+               xOrigin + viewXOffset + radius,
+               yOrigin + viewYOffset + radius, utmZone,
+               minTileX, minTileY, maxTileX, maxTileY, zoomLevel);
+
+    for (int32_t r = minTileY; r <= maxTileY; ++r)
+    {
+        for (int32_t c = minTileX; c <= maxTileX; ++c)
+        {
+            QString url = getTileLocation(c, r, zoomLevel, tileResolution);
+
+            TexturePtr t = textureCache->get(url, useHeightModel);
+        }
+    }
+}
+
+void
+Imagery::draw3D(double radius, double tileResolution,
+                double xOrigin, double yOrigin,
+                double viewXOffset, double viewYOffset,
+                const QString& utmZone, bool useHeightModel)
+{
+    int32_t minTileX, minTileY, maxTileX, maxTileY;
+    int32_t zoomLevel;
+
+    tileBounds(tileResolution,
+               xOrigin + viewXOffset - radius,
+               yOrigin + viewYOffset - radius,
+               xOrigin + viewXOffset + radius,
+               yOrigin + viewYOffset + radius, utmZone,
+               minTileX, minTileY, maxTileX, maxTileY, zoomLevel);
+
+    for (int32_t r = minTileY; r <= maxTileY; ++r)
+    {
+        for (int32_t c = minTileX; c <= maxTileX; ++c)
+        {
+            QString tileURL = getTileLocation(c, r, zoomLevel, tileResolution);
+
+            double x1, y1, x2, y2, x3, y3, x4, y4;
+            imageBounds(c, r, tileResolution, x1, y1, x2, y2, x3, y3, x4, y4);
+
+            TexturePtr t = textureCache->get(tileURL, useHeightModel);
+
+            if (!t.isNull())
+            {
+                t->draw(x1 - xOrigin, y1 - yOrigin,
+                        x2 - xOrigin, y2 - yOrigin,
+                        x3 - xOrigin, y3 - yOrigin,
+                        x4 - xOrigin, y4 - yOrigin, true);
+            }
+        }
+    }
+}
+
+bool
+Imagery::update(void)
+{
+    textureCache->sync();
+
+    return true;
+}
+
+void
+Imagery::imageBounds(int32_t tileX, int32_t tileY, double tileResolution,
+                     double& x1, double& y1, double& x2, double& y2,
+                     double& x3, double& y3, double& x4, double& y4) const
+{
+    if (currentImageryType == GOOGLE_MAP ||
+        currentImageryType == GOOGLE_SATELLITE)
+    {
+        int32_t zoomLevel = MAX_ZOOM_LEVEL - static_cast<int32_t>(rint(log2(tileResolution)));
+        int32_t numTiles = static_cast<int32_t>(exp2(static_cast<double>(zoomLevel)));
+
+        double lon1 = tileXToLongitude(tileX, numTiles);
+        double lon2 = tileXToLongitude(tileX + 1, numTiles);
+
+        double lat1 = tileYToLatitude(tileY, numTiles);
+        double lat2 = tileYToLatitude(tileY + 1, numTiles);
+
+        QString utmZone;
+        LLtoUTM(lat1, lon1, x1, y1, utmZone);
+        LLtoUTM(lat1, lon2, x2, y2, utmZone);
+        LLtoUTM(lat2, lon2, x3, y3, utmZone);
+        LLtoUTM(lat2, lon1, x4, y4, utmZone);
+    }
+    else if (currentImageryType == SWISSTOPO_SATELLITE ||
+             currentImageryType == SWISSTOPO_SATELLITE_3D)
+    {
+        double utmMultiplier = tileResolution * 200.0;
+        double minX = tileX * utmMultiplier;
+        double maxX = minX + utmMultiplier;
+        double minY = tileY * utmMultiplier;
+        double maxY = minY + utmMultiplier;
+
+        x1 = maxX; y1 = minY;
+        x2 = maxX; y2 = maxY;
+        x3 = minX; y3 = maxY;
+        x4 = minX; y4 = minY;
+    }
+}
+
+void
+Imagery::tileBounds(double tileResolution,
+                    double minUtmX, double minUtmY,
+                    double maxUtmX, double maxUtmY, const QString& utmZone,
+                    int32_t& minTileX, int32_t& minTileY,
+                    int32_t& maxTileX, int32_t& maxTileY,
+                    int32_t& zoomLevel) const
+{
+    double centerUtmX = (maxUtmX - minUtmX) / 2.0 + minUtmX;
+    double centerUtmY = (maxUtmY - minUtmY) / 2.0 + minUtmY;
+    int32_t centerTileX, centerTileY;
+
+    if (currentImageryType == GOOGLE_MAP ||
+        currentImageryType == GOOGLE_SATELLITE)
+    {
+        UTMtoTile(minUtmX, minUtmY, utmZone, tileResolution,
+                  minTileX, maxTileY, zoomLevel);
+        UTMtoTile(centerUtmX, centerUtmY, utmZone, tileResolution,
+                  centerTileX, centerTileY, zoomLevel);
+        UTMtoTile(maxUtmX, maxUtmY, utmZone, tileResolution,
+                  maxTileX, minTileY, zoomLevel);
+    }
+    else if (currentImageryType == SWISSTOPO_SATELLITE ||
+             currentImageryType == SWISSTOPO_SATELLITE_3D)
+    {
+        double utmMultiplier = tileResolution * 200;
+
+        minTileX = static_cast<int32_t>(rint(minUtmX / utmMultiplier));
+        minTileY = static_cast<int32_t>(rint(minUtmY / utmMultiplier));
+        centerTileX = static_cast<int32_t>(rint(centerUtmX / utmMultiplier));
+        centerTileY = static_cast<int32_t>(rint(centerUtmY / utmMultiplier));
+        maxTileX = static_cast<int32_t>(rint(maxUtmX / utmMultiplier));
+        maxTileY = static_cast<int32_t>(rint(maxUtmY / utmMultiplier));
+    }
+
+    if (maxTileX - minTileX + 1 > 14)
+    {
+        minTileX = centerTileX - 7;
+        maxTileX = centerTileX + 6;
+    }
+    if (maxTileY - minTileY + 1 > 14)
+    {
+        minTileY = centerTileY - 7;
+        maxTileY = centerTileY + 6;
+    }
+}
+
+double
+Imagery::tileXToLongitude(int32_t tileX, int32_t numTiles) const
+{
+    return 360.0 * (static_cast<double>(tileX)
+                    / static_cast<double>(numTiles)) - 180.0;
+}
+
+double
+Imagery::tileYToLatitude(int32_t tileY, int32_t numTiles) const
+{
+    double unnormalizedRad =
+            (static_cast<double>(tileY) / static_cast<double>(numTiles))
+            * 2.0 * M_PI - M_PI;
+    double rad = 2.0 * atan(exp(unnormalizedRad)) - M_PI / 2.0;
+    return -rad * 180.0 / M_PI;
+}
+
+int32_t
+Imagery::longitudeToTileX(double longitude, int32_t numTiles) const
+{
+    return static_cast<int32_t>((longitude / 180.0 + 1.0) / 2.0 * numTiles);
+}
+
+int32_t
+Imagery::latitudeToTileY(double latitude, int32_t numTiles) const
+{
+    double rad = latitude * M_PI / 180.0;
+    double normalizedRad = -log(tan(rad) + 1.0 / cos(rad));
+    return static_cast<int32_t>((normalizedRad + M_PI)
+                                / (2.0 * M_PI) * numTiles);
+}
+
+void
+Imagery::UTMtoTile(double northing, double easting, const QString& utmZone,
+                   double tileResolution, int32_t& tileX, int32_t& tileY,
+                   int32_t& zoomLevel) const
+{
+    double latitude, longitude;
+
+    UTMtoLL(northing, easting, utmZone, latitude, longitude);
+
+    zoomLevel = MAX_ZOOM_LEVEL - static_cast<int32_t>(rint(log2(tileResolution)));
+    int32_t numTiles = static_cast<int32_t>(exp2(static_cast<double>(zoomLevel)));
+
+    tileX = longitudeToTileX(longitude, numTiles);
+    tileY = latitudeToTileY(latitude, numTiles);
+}
+
+QChar
+Imagery::UTMLetterDesignator(double latitude) const
+{
+    // This routine determines the correct UTM letter designator for the given latitude
+    // returns 'Z' if latitude is outside the UTM limits of 84N to 80S
+    // Written by Chuck Gantz- chuck.gantz@globalstar.com
+    char letterDesignator;
+
+    if ((84.0 >= latitude) && (latitude >= 72.0)) letterDesignator = 'X';
+    else if ((72.0 > latitude) && (latitude >= 64.0)) letterDesignator = 'W';
+    else if ((64.0 > latitude) && (latitude >= 56.0)) letterDesignator = 'V';
+    else if ((56.0 > latitude) && (latitude >= 48.0)) letterDesignator = 'U';
+    else if ((48.0 > latitude) && (latitude >= 40.0)) letterDesignator = 'T';
+    else if ((40.0 > latitude) && (latitude >= 32.0)) letterDesignator = 'S';
+    else if ((32.0 > latitude) && (latitude >= 24.0)) letterDesignator = 'R';
+    else if ((24.0 > latitude) && (latitude >= 16.0)) letterDesignator = 'Q';
+    else if ((16.0 > latitude) && (latitude >= 8.0)) letterDesignator = 'P';
+    else if (( 8.0 > latitude) && (latitude >= 0.0)) letterDesignator = 'N';
+    else if (( 0.0 > latitude) && (latitude >= -8.0)) letterDesignator = 'M';
+    else if ((-8.0 > latitude) && (latitude >= -16.0)) letterDesignator = 'L';
+    else if ((-16.0 > latitude) && (latitude >= -24.0)) letterDesignator = 'K';
+    else if ((-24.0 > latitude) && (latitude >= -32.0)) letterDesignator = 'J';
+    else if ((-32.0 > latitude) && (latitude >= -40.0)) letterDesignator = 'H';
+    else if ((-40.0 > latitude) && (latitude >= -48.0)) letterDesignator = 'G';
+    else if ((-48.0 > latitude) && (latitude >= -56.0)) letterDesignator = 'F';
+    else if ((-56.0 > latitude) && (latitude >= -64.0)) letterDesignator = 'E';
+    else if ((-64.0 > latitude) && (latitude >= -72.0)) letterDesignator = 'D';
+    else if ((-72.0 > latitude) && (latitude >= -80.0)) letterDesignator = 'C';
+    else letterDesignator = 'Z'; //This is here as an error flag to show that the Latitude is outside the UTM limits
+
+    return letterDesignator;
+}
+
+void
+Imagery::LLtoUTM(double latitude, double longitude,
+                 double& utmNorthing, double& utmEasting,
+                 QString& utmZone) const
+{
+    // converts lat/long to UTM coords.  Equations from USGS Bulletin 1532
+    // East Longitudes are positive, West longitudes are negative.
+    // North latitudes are positive, South latitudes are negative
+    // Lat and Long are in decimal degrees
+    // Written by Chuck Gantz- chuck.gantz@globalstar.com
+
+    double k0 = 0.9996;
+
+    double LongOrigin;
+    double eccPrimeSquared;
+    double N, T, C, A, M;
+
+    double LatRad = latitude * M_PI / 180.0;
+    double LongRad = longitude * M_PI / 180.0;
+    double LongOriginRad;
+
+    int32_t ZoneNumber = static_cast<int32_t>((longitude + 180.0) / 6.0) + 1;
+
+    if (latitude >= 56.0 && latitude < 64.0 &&
+        longitude >= 3.0 && longitude < 12.0)
+    {
+        ZoneNumber = 32;
+    }
+
+    // Special zones for Svalbard
+    if (latitude >= 72.0 && latitude < 84.0)
+    {
+        if (     longitude >= 0.0  && longitude <  9.0) ZoneNumber = 31;
+        else if (longitude >= 9.0  && longitude < 21.0) ZoneNumber = 33;
+        else if (longitude >= 21.0 && longitude < 33.0) ZoneNumber = 35;
+        else if (longitude >= 33.0 && longitude < 42.0) ZoneNumber = 37;
+     }
+    LongOrigin = static_cast<double>((ZoneNumber - 1) * 6 - 180 + 3);  //+3 puts origin in middle of zone
+    LongOriginRad = LongOrigin * M_PI / 180.0;
+
+    // compute the UTM Zone from the latitude and longitude
+    utmZone = QString("%1%2").arg(ZoneNumber).arg(UTMLetterDesignator(latitude));
+
+    eccPrimeSquared = WGS84_ECCSQ / (1.0 - WGS84_ECCSQ);
+
+    N = WGS84_A / sqrt(1.0f - WGS84_ECCSQ * sin(LatRad) * sin(LatRad));
+    T = tan(LatRad) * tan(LatRad);
+    C = eccPrimeSquared * cos(LatRad) * cos(LatRad);
+    A = cos(LatRad) * (LongRad - LongOriginRad);
+
+    M = WGS84_A * ((1.0 - WGS84_ECCSQ / 4.0
+                    - 3.0 * WGS84_ECCSQ * WGS84_ECCSQ / 64.0
+                    - 5.0 * WGS84_ECCSQ * WGS84_ECCSQ * WGS84_ECCSQ / 256.0)
+                   * LatRad
+                   - (3.0 * WGS84_ECCSQ / 8.0
+                      + 3.0 * WGS84_ECCSQ * WGS84_ECCSQ / 32.0
+                      + 45.0 * WGS84_ECCSQ * WGS84_ECCSQ * WGS84_ECCSQ / 1024.0)
+                   * sin(2.0 * LatRad)
+                   + (15.0 * WGS84_ECCSQ * WGS84_ECCSQ / 256.0
+                      + 45.0 * WGS84_ECCSQ * WGS84_ECCSQ * WGS84_ECCSQ / 1024.0)
+                   * sin(4.0 * LatRad)
+                   - (35.0 * WGS84_ECCSQ * WGS84_ECCSQ * WGS84_ECCSQ / 3072.0)
+                   * sin(6.0 * LatRad));
+
+    utmEasting = k0 * N * (A + (1.0 - T + C) * A * A * A / 6.0
+                           + (5.0 - 18.0 * T + T * T + 72.0 * C
+                              - 58.0 * eccPrimeSquared)
+                           * A * A * A * A * A / 120.0)
+                 + 500000.0;
+
+    utmNorthing = k0 * (M + N * tan(LatRad) *
+                        (A * A / 2.0 +
+                         (5.0 - T + 9.0 * C + 4.0 * C * C) * A * A * A * A / 24.0
+                         + (61.0 - 58.0 * T + T * T + 600.0 * C
+                            - 330.0 * eccPrimeSquared)
+                         * A * A * A * A * A * A / 720.0));
+    if (latitude < 0.0)
+    {
+        utmNorthing += 10000000.0; //10000000 meter offset for southern hemisphere
+    }
+}
+
+void
+Imagery::UTMtoLL(double utmNorthing, double utmEasting, const QString& utmZone,
+                 double& latitude, double& longitude) const
+{
+    // converts UTM coords to lat/long.  Equations from USGS Bulletin 1532
+    // East Longitudes are positive, West longitudes are negative.
+    // North latitudes are positive, South latitudes are negative
+    // Lat and Long are in decimal degrees.
+    // Written by Chuck Gantz- chuck.gantz@globalstar.com
+
+    double k0 = 0.9996;
+    double eccPrimeSquared;
+    double e1 = (1.0 - sqrt(1.0 - WGS84_ECCSQ)) / (1.0 + sqrt(1.0 - WGS84_ECCSQ));
+    double N1, T1, C1, R1, D, M;
+    double LongOrigin;
+    double mu, phi1, phi1Rad;
+    double x, y;
+    int32_t ZoneNumber;
+    char ZoneLetter;
+    bool NorthernHemisphere;
+
+    x = utmEasting - 500000.0; //remove 500,000 meter offset for longitude
+    y = utmNorthing;
+
+    std::istringstream iss(utmZone.toStdString());
+    iss >> ZoneNumber >> ZoneLetter;
+    if ((ZoneLetter - 'N') >= 0)
+    {
+        NorthernHemisphere = true;//point is in northern hemisphere
+    }
+    else
+    {
+        NorthernHemisphere = false;//point is in southern hemisphere
+        y -= 10000000.0;//remove 10,000,000 meter offset used for southern hemisphere
+    }
+
+    LongOrigin = (ZoneNumber - 1.0) * 6.0 - 180.0 + 3.0;  //+3 puts origin in middle of zone
+
+    eccPrimeSquared = WGS84_ECCSQ / (1.0 - WGS84_ECCSQ);
+
+    M = y / k0;
+    mu = M / (WGS84_A * (1.0 - WGS84_ECCSQ / 4.0
+                         - 3.0 * WGS84_ECCSQ * WGS84_ECCSQ / 64.0
+                         - 5.0 * WGS84_ECCSQ * WGS84_ECCSQ * WGS84_ECCSQ / 256.0));
+
+    phi1Rad = mu + (3.0 * e1 / 2.0 - 27.0 * e1 * e1 * e1 / 32.0) * sin(2.0 * mu)
+              + (21.0 * e1 * e1 / 16.0 - 55.0 * e1 * e1 * e1 * e1 / 32.0)
+              * sin(4.0 * mu)
+              + (151.0 * e1 * e1 * e1 / 96.0) * sin(6.0 * mu);
+    phi1 = phi1Rad / M_PI * 180.0;
+
+    N1 = WGS84_A / sqrt(1.0 - WGS84_ECCSQ * sin(phi1Rad) * sin(phi1Rad));
+    T1 = tan(phi1Rad) * tan(phi1Rad);
+    C1 = eccPrimeSquared * cos(phi1Rad) * cos(phi1Rad);
+    R1 = WGS84_A * (1.0 - WGS84_ECCSQ) /
+         pow(1.0 - WGS84_ECCSQ * sin(phi1Rad) * sin(phi1Rad), 1.5);
+    D = x / (N1 * k0);
+
+    latitude = phi1Rad - (N1 * tan(phi1Rad) / R1)
+               * (D * D / 2.0 - (5.0 + 3.0 * T1 + 10.0 * C1 - 4.0 * C1 * C1
+                                 - 9.0 * eccPrimeSquared) * D * D * D * D / 24.0
+                  + (61.0 + 90.0 * T1 + 298.0 * C1 + 45.0 * T1 * T1
+                     - 252.0 * eccPrimeSquared - 3.0 * C1 * C1)
+                  * D * D * D * D * D * D / 720.0);
+    latitude *= 180.0 / M_PI;
+
+    longitude = (D - (1.0 + 2.0 * T1 + C1) * D * D * D / 6.0
+                 + (5.0 - 2.0 * C1 + 28.0 * T1 - 3.0 * C1 * C1
+                    + 8.0 * eccPrimeSquared + 24.0 * T1 * T1)
+                 * D * D * D * D * D / 120.0) / cos(phi1Rad);
+    longitude = LongOrigin + longitude / M_PI * 180.0;
+}
+
+QString
+Imagery::getTileLocation(int32_t tileX, int32_t tileY, int32_t zoomLevel,
+                         double tileResolution) const
+{
+    std::ostringstream oss;
+
+    switch (currentImageryType)
+    {
+    case GOOGLE_MAP:
+        oss << "http://mt0.google.com/vt/lyrs=m@120&x=" << tileX
+            << "&y=" << tileY << "&z=" << zoomLevel;
+        break;
+    case GOOGLE_SATELLITE:
+        oss << "http://khm.google.com/vt/lbw/lyrs=y&x=" << tileX
+            << "&y=" << tileY << "&z=" << zoomLevel;
+        break;
+    case SWISSTOPO_SATELLITE: case SWISSTOPO_SATELLITE_3D:
+        oss << "../map/eth_zurich_swissimage_025/200/color/" << tileY
+            << "/tile-";
+        if (tileResolution < 1.0)
+        {
+            oss << std::fixed << std::setprecision(2) << tileResolution;
+        }
+        else
+        {
+            oss << static_cast<int32_t>(rint(tileResolution));
+        }
+        oss << "-" << tileY << "-" << tileX << ".jpg";
+    default:
+        {};
+    }
+
+    QString url(oss.str().c_str());
+
+    return url;
+}

src/ui/map3D/Pixhawk3DWidget.cc

@@ -172,7 +172,9 @@ Pixhawk3DWidget::showWaypoints(int state)
 void
 Pixhawk3DWidget::selectVehicleModel(int index)
 {
+    egocentricMap->removeChild(vehicleModel);
     vehicleModel = vehicleModels.at(index);
+    egocentricMap->addChild(vehicleModel);
 }
 
 void
@@ -201,7 +203,7 @@ Pixhawk3DWidget::toggleFollowCamera(int32_t state)
         followCamera = false;
     }
 }
-
+#include <osgDB/WriteFile>
 QVector< osg::ref_ptr<osg::Node> >
 Pixhawk3DWidget::findVehicleModels(void)
 {
@@ -211,14 +213,15 @@ Pixhawk3DWidget::findVehicleModels(void)
     QVector< osg::ref_ptr<osg::Node> > nodes;
 
     // add Pixhawk Bravo model
-    vehicleModels.push_back(PixhawkCheetahGeode::instance());
+    nodes.push_back(PixhawkCheetahGeode::instance());
 
+    // add all other models in folder
     for (int i = 0; i < files.size(); ++i)
     {
         osg::ref_ptr<osg::Node> node =
                 osgDB::readNodeFile(directory.absoluteFilePath(files[i]).toStdString().c_str());
 
-        vehicleModels.push_back(node);
+        nodes.push_back(node);
     }
 
     return nodes;
@@ -264,11 +267,11 @@ Pixhawk3DWidget::buildLayout(void)
     layout->addWidget(gridCheckBox, 1, 0);
     layout->addWidget(trailCheckBox, 1, 1);
     layout->addWidget(waypointsCheckBox, 1, 2);
-    layout->addItem(new QSpacerItem(20, 0, QSizePolicy::Expanding, QSizePolicy::Expanding), 1, 3);
+    layout->addItem(new QSpacerItem(10, 0, QSizePolicy::Expanding, QSizePolicy::Expanding), 1, 3);
     layout->addWidget(modelLabel, 1, 4);
     layout->addWidget(modelComboBox, 1, 5);
     layout->addWidget(targetButton, 1, 6);
-    layout->addItem(new QSpacerItem(20, 0, QSizePolicy::Expanding, QSizePolicy::Expanding), 1, 7);
+    layout->addItem(new QSpacerItem(10, 0, QSizePolicy::Expanding, QSizePolicy::Expanding), 1, 7);
     layout->addWidget(recenterButton, 1, 8);
     layout->addWidget(followCameraCheckBox, 1, 9);
     layout->setRowStretch(0, 100);

src/ui/map3D/Q3DWidget.cc

@@ -35,10 +35,6 @@ This file is part of the QGROUNDCONTROL project
 #include <osg/LineWidth>
 #include <osg/MatrixTransform>
 
-static const float KEY_ROTATE_AMOUNT = 5.0f;
-static const float KEY_MOVE_AMOUNT   = 10.0f;
-static const float KEY_ZOOM_AMOUNT   = 5.0f;
-
 Q3DWidget::Q3DWidget(QWidget* parent)
     : QGLWidget(parent)
     , root(new osg::Group())

src/ui/map3D/Texture.cc

+/*=====================================================================
+
+QGroundControl Open Source Ground Control Station
+
+(c) 2009, 2010 QGROUNDCONTROL PROJECT <http://www.qgroundcontrol.org>
+
+This file is part of the QGROUNDCONTROL project
+
+    QGROUNDCONTROL is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    QGROUNDCONTROL is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with QGROUNDCONTROL. If not, see <http://www.gnu.org/licenses/>.
+
+======================================================================*/
+
+/**
+ * @file
+ *   @brief Definition of the class Texture.
+ *
+ *   @author Lionel Heng <hengli@student.ethz.ch>
+ *
+ */
+
+#include "Texture.h"
+
+Texture::Texture()
+    : _is3D(false)
+{
+
+}
+
+const QString&
+Texture::getSourceURL(void) const
+{
+    return sourceURL;
+}
+
+void
+Texture::setID(GLuint id)
+{
+    this->id = id;
+}
+
+void
+Texture::sync(const WebImagePtr& image)
+{
+    state = static_cast<State>(image->getState());
+
+    if (image->getState() != WebImage::UNINITIALIZED &&
+        (sourceURL != image->getSourceURL() ||
+         _is3D != image->is3D()))
+    {
+        sourceURL = image->getSourceURL();
+        _is3D = image->is3D();
+    }
+
+    if (image->getState() == WebImage::READY && image->getSyncFlag())
+    {
+        image->setSyncFlag(false);
+
+        if (image->getWidth() != imageWidth ||
+            image->getHeight() != imageHeight)
+        {
+            imageWidth = image->getWidth();
+            textureWidth = 32;
+            while (textureWidth < imageWidth)
+            {
+                textureWidth *= 2;
+            }
+            imageHeight = image->getHeight();
+            textureHeight = 32;
+            while (textureHeight < imageHeight)
+            {
+                textureHeight *= 2;
+            }
+
+            maxU = static_cast<double>(imageWidth)
+                   / static_cast<double>(textureWidth);
+            maxV = static_cast<double>(imageHeight)
+                   / static_cast<double>(textureHeight);
+
+            glBindTexture(GL_TEXTURE_2D, id);
+            glTexImage2D(GL_TEXTURE_2D, 0, 3, textureWidth, textureHeight,
+                         0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
+        }
+
+        glBindTexture(GL_TEXTURE_2D, id);
+        glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, imageWidth, imageHeight,
+                        GL_RGBA, GL_UNSIGNED_BYTE, image->getImageData());
+
+        heightModel = image->getHeightModel();
+    }
+}
+
+void
+Texture::draw(float x1, float y1, float x2, float y2,
+              bool smoothInterpolation) const
+{
+    draw(x1, y1, x2, y1, x2, y2, x1, y2, smoothInterpolation);
+}
+
+void
+Texture::draw(float x1, float y1, float x2, float y2,
+              float x3, float y3, float x4, float y4,
+              bool smoothInterpolation) const
+{
+    if (state == REQUESTED)
+    {
+        glBegin(GL_LINE_LOOP);
+        glColor3f(0.0f, 0.0f, 1.0f);
+        glVertex2f(x1, y1);
+        glVertex2f(x2, y2);
+        glVertex2f(x3, y3);
+        glVertex2f(x4, y4);
+        glEnd();
+
+        return;
+    }
+
+    glEnable(GL_TEXTURE_2D);
+    glBindTexture(GL_TEXTURE_2D, id);
+
+    float dx, dy;
+    if (smoothInterpolation)
+    {
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+        dx = 1.0f / (2.0f * textureWidth);
+        dy = 1.0f / (2.0f * textureHeight);
+    }
+    else
+    {
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+        dx = 0.0f;
+        dy = 0.0f;
+    }
+
+    glColor3f(1.0f, 1.0f, 1.0f);
+    if (!_is3D)
+    {
+        glBegin(GL_QUADS);
+        glTexCoord2f(dx, maxV - dy);
+        glVertex3f(x1, y1, 0.0f);
+        glTexCoord2f(maxU - dx, maxV - dy);
+        glVertex3f(x2, y2, 0.0f);
+        glTexCoord2f(maxU - dx, dy);
+        glVertex3f(x3, y3, 0.0f);
+        glTexCoord2f(dx, dy);
+        glVertex3f(x4, y4, 0.0f);
+        glEnd();
+    }
+    else
+    {
+        float scaleX = 1.0f / static_cast<float>(heightModel.size() - 1);
+
+        for (int32_t i = 0; i < heightModel.size() - 1; ++i)
+        {
+            float scaleI = scaleX * static_cast<float>(i);
+
+            float scaleY =
+                    1.0f / static_cast<float>(heightModel[i].size() - 1);
+
+            float x1i = x1 + scaleI * (x4 - x1);
+            float x1f = x2 + scaleI * (x3 - x2);
+            float x2i = x1i + scaleX * (x4 - x1);
+            float x2f = x1f + scaleX * (x3 - x2);
+
+            for (int32_t j = 0; j < heightModel[i].size() - 1; ++j)
+            {
+                float scaleJ = scaleY * static_cast<float>(j);
+
+                float y1i = y1 + scaleJ * (y2 - y1);
+                float y1f = y4 + scaleJ * (y3 - y4);
+                float y2i = y1i + scaleY * (y2 - y1);
+                float y2f = y1f + scaleY * (y3 - y4);
+
+                float nx1 = x1i + scaleJ * (x1f - x1i);
+                float nx2 = x1i + (scaleJ + scaleY) * (x1f - x1i);
+                float nx3 = x2i + (scaleJ + scaleY) * (x2f - x2i);
+                float nx4  = x2i + scaleJ * (x2f - x2i);
+                float ny1 = y1i + scaleI * (y1f - y1i);
+                float ny2 = y2i + scaleI * (y2f - y2i);
+                float ny3 = y2i + (scaleI + scaleX) * (y2f - y2i);
+                float ny4 = y1i + (scaleI + scaleX) * (y1f - y1i);
+
+                glBegin(GL_QUADS);
+                glTexCoord2f(dx + scaleJ * (maxU - dx * 2.0f),
+                             dy + (1.0f - scaleI) * (maxV - dy * 2.0f));
+                glVertex3f(nx1, ny1, -static_cast<float>(heightModel[i][j]));
+                glTexCoord2f(dx + (scaleJ + scaleY) * (maxU - dx * 2.0f),
+                             dy + (1.0f - scaleI) * (maxV - dy * 2.0f));
+                glVertex3f(nx2, ny2, -static_cast<float>(heightModel[i][j + 1]));
+                glTexCoord2f(dx + (scaleJ + scaleY) * (maxU - dx * 2.0f),
+                             dy + (1.0f - scaleI - scaleX) * (maxV - dy * 2.0f));
+                glVertex3f(nx3, ny3, -static_cast<float>(heightModel[i + 1][j + 1]));
+                glTexCoord2f(dx + scaleJ * (maxU - dx * 2.0f),
+                             dy + (1.0f - scaleI - scaleX) * (maxV - dy * 2.0f));
+                glVertex3f(nx4, ny4, -static_cast<float>(heightModel[i + 1][j]));
+
+                glEnd();
+            }
+        }
+    }
+
+    glDisable(GL_TEXTURE_2D);
+}
+
+bool
+Texture::is3D(void) const
+{
+    return _is3D;
+}

src/ui/map3D/Texture.h

+/*=====================================================================
+
+QGroundControl Open Source Ground Control Station
+
+(c) 2009, 2010 QGROUNDCONTROL PROJECT <http://www.qgroundcontrol.org>
+
+This file is part of the QGROUNDCONTROL project
+
+    QGROUNDCONTROL is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    QGROUNDCONTROL is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with QGROUNDCONTROL. If not, see <http://www.gnu.org/licenses/>.
+
+======================================================================*/
+
+/**
+ * @file
+ *   @brief Definition of the class Texture.
+ *
+ *   @author Lionel Heng <hengli@student.ethz.ch>
+ *
+ */
+
+#ifndef TEXTURE_H
+#define TEXTURE_H
+
+#if (defined __APPLE__) & (defined __MACH__)
+#include <OpenGL/gl.h>
+#else
+#include <GL/gl.h>
+#endif
+#include <inttypes.h>
+#include <QSharedPointer>
+
+#include "WebImage.h"
+
+class Texture
+{
+public:
+    Texture();
+
+    const QString& getSourceURL(void) const;
+
+    void setID(GLuint id);
+
+    void sync(const WebImagePtr& image);
+
+    void draw(float x1, float y1, float x2, float y2,
+              bool smoothInterpolation) const;
+    void draw(float x1, float y1, float x2, float y2,
+              float x3, float y3, float x4, float y4,
+              bool smoothInterpolation) const;
+
+    bool is3D(void) const;
+
+private:
+    enum State
+    {
+        UNINITIALIZED = 0,
+        REQUESTED = 1,
+        READY = 2
+    };
+
+    State state;
+    QString sourceURL;
+    GLuint id;
+
+    int32_t textureWidth;
+    int32_t textureHeight;
+
+    int32_t imageWidth;
+    int32_t imageHeight;
+
+    bool _is3D;
+    QVector< QVector<int32_t> > heightModel;
+
+    float maxU;
+    float maxV;
+};
+
+typedef QSharedPointer<Texture> TexturePtr;
+
+#endif // TEXTURE_H

src/ui/map3D/TextureCache.cc

+/*=====================================================================
+
+QGroundControl Open Source Ground Control Station
+
+(c) 2009, 2010 QGROUNDCONTROL PROJECT <http://www.qgroundcontrol.org>
+
+This file is part of the QGROUNDCONTROL project
+
+    QGROUNDCONTROL is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    QGROUNDCONTROL is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with QGROUNDCONTROL. If not, see <http://www.gnu.org/licenses/>.
+
+======================================================================*/
+
+/**
+ * @file
+ *   @brief Definition of the class TextureCache.
+ *
+ *   @author Lionel Heng <hengli@student.ethz.ch>
+ *
+ */
+
+#include "TextureCache.h"
+
+TextureCache::TextureCache(uint32_t _cacheSize)
+    : cacheSize(_cacheSize)
+    , imageCache(new WebImageCache(0, cacheSize))
+{
+    for (uint32_t i = 0; i < cacheSize; ++i)
+    {
+        TexturePtr t(new Texture);
+
+        GLuint id;
+        glGenTextures(1, &id);
+        t->setID(id);
+        glBindTexture(GL_TEXTURE_2D, id);
+        glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+
+        textures.push_back(t);
+    }
+}
+
+TexturePtr
+TextureCache::get(const QString& tileURL, bool useHeightModel)
+{
+    QPair<TexturePtr, int32_t> p1 = lookup(tileURL, useHeightModel);
+    if (!p1.first.isNull())
+    {
+        return p1.first;
+    }
+
+    QPair<WebImagePtr, int32_t> p2 =
+            imageCache->lookup(tileURL, useHeightModel);
+    if (!p2.first.isNull())
+    {
+        textures[p2.second]->sync(p2.first);
+        p1 = lookup(tileURL, useHeightModel);
+
+        return p1.first;
+    }
+
+    return TexturePtr();
+}
+
+void
+TextureCache::sync(void)
+{
+    if (requireSync())
+    {
+        for (int32_t i = 0; i < textures.size(); ++i)
+        {
+            textures[i]->sync(imageCache->at(i));
+        }
+    }
+}
+
+QPair<TexturePtr, int32_t>
+TextureCache::lookup(const QString& tileURL, bool useHeightModel)
+{
+    for (int32_t i = 0; i < textures.size(); ++i)
+    {
+        if (textures[i]->getSourceURL() == tileURL &&
+            textures[i]->is3D() == useHeightModel)
+        {
+            return qMakePair(textures[i], i);
+        }
+    }
+
+    return qMakePair(TexturePtr(), -1);
+}
+
+bool
+TextureCache::requireSync(void) const
+{
+    for (uint32_t i = 0; i < cacheSize; ++i)
+    {
+        if (imageCache->at(i)->getSyncFlag())
+        {
+            return true;
+        }
+    }
+    return false;
+}

src/ui/map3D/TextureCache.h

+/*=====================================================================
+
+QGroundControl Open Source Ground Control Station
+
+(c) 2009, 2010 QGROUNDCONTROL PROJECT <http://www.qgroundcontrol.org>
+
+This file is part of the QGROUNDCONTROL project
+
+    QGROUNDCONTROL is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    QGROUNDCONTROL is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with QGROUNDCONTROL. If not, see <http://www.gnu.org/licenses/>.
+
+======================================================================*/
+
+/**
+ * @file
+ *   @brief Definition of the class TextureCache.
+ *
+ *   @author Lionel Heng <hengli@student.ethz.ch>
+ *
+ */
+
+#ifndef TEXTURECACHE_H
+#define TEXTURECACHE_H
+
+#include <QVector>
+
+#include "Texture.h"
+#include "WebImageCache.h"
+
+class TextureCache
+{
+public:
+    explicit TextureCache(uint32_t cacheSize);
+
+    TexturePtr get(const QString& tileURL, bool useHeightModel = false);
+
+    void sync(void);
+
+private:
+    QPair<TexturePtr, int32_t> lookup(const QString& tileURL,
+                                      bool useHeightModel);
+
+    bool requireSync(void) const;
+
+    uint32_t cacheSize;
+    QVector<TexturePtr> textures;
+
+    QScopedPointer<WebImageCache> imageCache;
+};
+
+#endif // TEXTURECACHE_H

src/ui/map3D/WebImage.cc

+/*=====================================================================
+
+QGroundControl Open Source Ground Control Station
+
+(c) 2009, 2010 QGROUNDCONTROL PROJECT <http://www.qgroundcontrol.org>
+
+This file is part of the QGROUNDCONTROL project
+
+    QGROUNDCONTROL is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    QGROUNDCONTROL is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with QGROUNDCONTROL. If not, see <http://www.gnu.org/licenses/>.
+
+======================================================================*/
+
+/**
+ * @file
+ *   @brief Definition of the class WebImage.
+ *
+ *   @author Lionel Heng <hengli@student.ethz.ch>
+ *
+ */
+
+#include "WebImage.h"
+
+#include <QFile>
+#include <QGLWidget>
+
+WebImage::WebImage()
+    : state(WebImage::UNINITIALIZED)
+    , sourceURL("")
+    , image(0)
+    , lastReference(0)
+    , _is3D(false)
+    , syncFlag(false)
+{
+
+}
+
+void
+WebImage::clear(void)
+{
+    image.reset();
+    sourceURL.clear();
+    state = WebImage::UNINITIALIZED;
+    lastReference = 0;
+    heightModel.clear();
+}
+
+WebImage::State
+WebImage::getState(void) const
+{
+    return state;
+}
+
+void
+WebImage::setState(State state)
+{
+    this->state = state;
+}
+
+const QString&
+WebImage::getSourceURL(void) const
+{
+    return sourceURL;
+}
+
+void
+WebImage::setSourceURL(const QString& url)
+{
+    sourceURL = url;
+}
+
+const uint8_t*
+WebImage::getImageData(void) const
+{
+    return image->scanLine(0);
+}
+
+const QVector< QVector<int32_t> >&
+WebImage::getHeightModel(void) const
+{
+    return heightModel;
+}
+
+bool
+WebImage::setData(const QByteArray& data)
+{
+    QImage tempImage;
+    if (tempImage.loadFromData(data))
+    {
+        if (image.isNull())
+        {
+            image.reset(new QImage);
+        }
+        *image = QGLWidget::convertToGLFormat(tempImage);
+
+        return true;
+    }
+    else
+    {
+        return false;
+    }
+}
+
+bool
+WebImage::setData(const QString& filename)
+{
+    QImage tempImage;
+    if (tempImage.load(filename))
+    {
+        if (image.isNull())
+        {
+            image.reset(new QImage);
+        }
+        *image = QGLWidget::convertToGLFormat(tempImage);
+
+        return true;
+    }
+    else
+    {
+        return false;
+    }
+}
+
+bool
+WebImage::setData(const QString& imageFilename, const QString& heightFilename)
+{
+    QFile heightFile(heightFilename);
+
+    QImage tempImage;
+    if (tempImage.load(imageFilename) && heightFile.open(QIODevice::ReadOnly))
+    {
+        if (image.isNull())
+        {
+            image.reset(new QImage);
+        }
+        *image = QGLWidget::convertToGLFormat(tempImage);
+
+        QDataStream heightDataStream(&heightFile);
+
+        // read in width and height values for height map
+        char header[8];
+        heightDataStream.readRawData(header, 8);
+
+        int32_t height = *(reinterpret_cast<int32_t *>(header));
+        int32_t width = *(reinterpret_cast<int32_t *>(header + 4));
+
+        char buffer[height * width * sizeof(int32_t)];
+        heightDataStream.readRawData(buffer, height * width * sizeof(int32_t));
+
+        heightModel.clear();
+        for (int32_t i = 0; i < height; ++i)
+        {
+            QVector<int32_t> scanline;
+            for (int32_t j = 0; j < width; ++j)
+            {    
+                int32_t n = *(reinterpret_cast<int32_t *>(buffer
+                                                          + (i * height + j)
+                                                          * sizeof(int32_t)));
+                scanline.push_back(n);
+            }
+            heightModel.push_back(scanline);
+        }
+
+        heightFile.close();
+
+        _is3D = true;
+
+        return true;
+    }
+    else
+    {
+        return false;
+    }
+}
+
+int32_t
+WebImage::getWidth(void) const
+{
+    return image->width();
+}
+
+int32_t
+WebImage::getHeight(void) const
+{
+    return image->height();
+}
+
+int32_t
+WebImage::getByteCount(void) const
+{
+    return image->byteCount();
+}
+
+bool
+WebImage::is3D(void) const
+{
+    return _is3D;
+}
+
+uint64_t
+WebImage::getLastReference(void) const
+{
+    return lastReference;
+}
+
+void
+WebImage::setLastReference(uint64_t value)
+{
+    lastReference = value;
+}
+
+bool
+WebImage::getSyncFlag(void) const
+{
+    return syncFlag;
+}
+
+void
+WebImage::setSyncFlag(bool onoff)
+{
+    syncFlag = onoff;
+}

src/ui/map3D/WebImage.h

+/*=====================================================================
+
+QGroundControl Open Source Ground Control Station
+
+(c) 2009, 2010 QGROUNDCONTROL PROJECT <http://www.qgroundcontrol.org>
+
+This file is part of the QGROUNDCONTROL project
+
+    QGROUNDCONTROL is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    QGROUNDCONTROL is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with QGROUNDCONTROL. If not, see <http://www.gnu.org/licenses/>.
+
+======================================================================*/
+
+/**
+ * @file
+ *   @brief Definition of the class WebImage.
+ *
+ *   @author Lionel Heng <hengli@student.ethz.ch>
+ *
+ */
+
+#ifndef WEBIMAGE_H
+#define WEBIMAGE_H
+
+#include <inttypes.h>
+#include <QImage>
+#include <QScopedPointer>
+#include <QSharedPointer>
+
+class WebImage
+{
+public:
+    WebImage();
+
+    void clear(void);
+
+    enum State
+    {
+        UNINITIALIZED = 0,
+        REQUESTED = 1,
+        READY = 2
+    };
+
+    State getState(void) const;
+    void setState(State state);
+
+    const QString& getSourceURL(void) const;
+    void setSourceURL(const QString& url);
+
+    const uint8_t* getImageData(void) const;
+    const QVector< QVector<int32_t> >& getHeightModel(void) const;
+    bool setData(const QByteArray& data);
+    bool setData(const QString& filename);
+    bool setData(const QString& imageFilename, const QString& heightFilename);
+
+    int32_t getWidth(void) const;
+    int32_t getHeight(void) const;
+    int32_t getByteCount(void) const;
+
+    bool is3D(void) const;
+
+    uint64_t getLastReference(void) const;
+    void setLastReference(uint64_t value);
+
+    bool getSyncFlag(void) const;
+    void setSyncFlag(bool onoff);
+
+private:
+    State state;
+    QString sourceURL;
+    QScopedPointer<QImage> image;
+    QVector< QVector<int32_t> > heightModel;
+    uint64_t lastReference;
+    bool _is3D;
+    bool syncFlag;
+};
+
+typedef QSharedPointer<WebImage> WebImagePtr;
+
+#endif // WEBIMAGE_H

src/ui/map3D/WebImageCache.cc

+/*=====================================================================
+
+QGroundControl Open Source Ground Control Station
+
+(c) 2009, 2010 QGROUNDCONTROL PROJECT <http://www.qgroundcontrol.org>
+
+This file is part of the QGROUNDCONTROL project
+
+    QGROUNDCONTROL is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    QGROUNDCONTROL is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with QGROUNDCONTROL. If not, see <http://www.gnu.org/licenses/>.
+
+======================================================================*/
+
+/**
+ * @file
+ *   @brief Definition of the class WebImageCache.
+ *
+ *   @author Lionel Heng <hengli@student.ethz.ch>
+ *
+ */
+
+#include "WebImageCache.h"
+
+#include <QNetworkReply>
+#include <QPixmap>
+
+WebImageCache::WebImageCache(QObject* parent, uint32_t _cacheSize)
+    : QObject(parent)
+    , cacheSize(_cacheSize)
+    , currentReference(0)
+    , networkManager(new QNetworkAccessManager)
+{
+    for (uint32_t i = 0; i < cacheSize; ++i)
+    {
+        WebImagePtr image(new WebImage);
+
+        webImages.push_back(image);
+    }
+
+    connect(networkManager.data(), SIGNAL(finished(QNetworkReply*)),
+            this, SLOT(downloadFinished(QNetworkReply*)));
+}
+
+QPair<WebImagePtr, int32_t>
+WebImageCache::lookup(const QString& url, bool useHeightModel)
+{
+    QPair<WebImagePtr, int32_t> cacheEntry;
+
+    for (int32_t i = 0; i < webImages.size(); ++i)
+    {
+        if (webImages[i]->getState() != WebImage::UNINITIALIZED &&
+            webImages[i]->getSourceURL() == url &&
+            webImages[i]->is3D() == useHeightModel)
+        {
+            cacheEntry.first = webImages[i];
+            cacheEntry.second = i;
+            break;
+        }
+    }
+
+    if (cacheEntry.first.isNull())
+    {
+        for (int32_t i = 0; i < webImages.size(); ++i)
+        {
+            // get uninitialized image
+            if (webImages[i]->getState() == WebImage::UNINITIALIZED)
+            {
+                cacheEntry.first = webImages[i];
+                cacheEntry.second = i;
+                break;
+            }
+            // get oldest image
+            else if (webImages[i]->getState() == WebImage::READY &&
+                     (cacheEntry.first.isNull() ||
+                      webImages[i]->getLastReference() <
+                      cacheEntry.first->getLastReference()))
+            {
+                cacheEntry.first = webImages[i];
+                cacheEntry.second = i;
+            }
+        }
+
+        if (cacheEntry.first.isNull())
+        {
+            return qMakePair(WebImagePtr(), -1);
+        }
+        else
+        {
+            if (cacheEntry.first->getState() == WebImage::READY)
+            {
+                cacheEntry.first->clear();
+            }
+            cacheEntry.first->setSourceURL(url);
+            cacheEntry.first->setLastReference(currentReference);
+            ++currentReference;
+            cacheEntry.first->setState(WebImage::REQUESTED);
+
+            if (url.left(4).compare("http") == 0)
+            {
+                networkManager->get(QNetworkRequest(QUrl(url)));
+            }
+            else
+            {
+                bool success;
+
+                if (useHeightModel)
+                {
+                    QString heightURL = url;
+                    heightURL.replace("color", "dom");
+                    heightURL.replace(".jpg", ".txt");
+
+                    success = cacheEntry.first->setData(url, heightURL);
+                }
+                else
+                {
+                    success = cacheEntry.first->setData(url);
+                }
+
+                if (success)
+                {
+                    cacheEntry.first->setSyncFlag(true);
+                    cacheEntry.first->setState(WebImage::READY);
+                }
+                else
+                {
+                    cacheEntry.first->setState(WebImage::UNINITIALIZED);
+                }
+            }
+
+            return cacheEntry;
+        }
+    }
+    else
+    {
+        if (cacheEntry.first->getState() == WebImage::READY)
+        {
+            cacheEntry.first->setLastReference(currentReference);
+            ++currentReference;
+            return cacheEntry;
+        }
+        else
+        {
+            return qMakePair(WebImagePtr(), -1);
+        }
+    }
+}
+
+WebImagePtr
+WebImageCache::at(int32_t index) const
+{
+    return webImages[index];
+}
+
+void
+WebImageCache::downloadFinished(QNetworkReply* reply)
+{
+    reply->deleteLater();
+
+    if (reply->error() != QNetworkReply::NoError)
+    {
+        return;
+    }
+    QVariant attribute = reply->attribute(QNetworkRequest::RedirectionTargetAttribute);
+    if (attribute.isValid())
+    {
+        return;
+    }
+
+    WebImagePtr image;
+    foreach(image, webImages)
+    {
+        if (reply->url().toString() == image->getSourceURL())
+        {
+            image->setData(reply->readAll());
+            image->setSyncFlag(true);
+            image->setState(WebImage::READY);
+
+            return;
+        }
+    }
+}

src/ui/map3D/WebImageCache.h

+/*=====================================================================
+
+QGroundControl Open Source Ground Control Station
+
+(c) 2009, 2010 QGROUNDCONTROL PROJECT <http://www.qgroundcontrol.org>
+
+This file is part of the QGROUNDCONTROL project
+
+    QGROUNDCONTROL is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    QGROUNDCONTROL is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with QGROUNDCONTROL. If not, see <http://www.gnu.org/licenses/>.
+
+======================================================================*/
+
+/**
+ * @file
+ *   @brief Definition of the class WebImageCache.
+ *
+ *   @author Lionel Heng <hengli@student.ethz.ch>
+ *
+ */
+
+#ifndef WEBIMAGECACHE_H
+#define WEBIMAGECACHE_H
+
+#include <QNetworkAccessManager>
+#include <QObject>
+#include <QPair>
+
+#include "WebImage.h"
+
+class WebImageCache : public QObject
+{
+    Q_OBJECT
+
+public:
+    WebImageCache(QObject* parent, uint32_t cacheSize);
+
+    QPair<WebImagePtr, int32_t> lookup(const QString& url,
+                                       bool useHeightModel);
+
+    WebImagePtr at(int32_t index) const;
+
+private Q_SLOTS:
+    void downloadFinished(QNetworkReply* reply);
+
+private:
+    uint32_t cacheSize;
+
+    QVector<WebImagePtr> webImages;
+    uint64_t currentReference;
+
+    QScopedPointer<QNetworkAccessManager> networkManager;
+};
+
+#endif // WEBIMAGECACHE_H