void TileLoader::start() {
// discard previous set of tiles and all pending requests
abort();
qnam_ = new QNetworkAccessManager(this);
QObject::connect(qnam_, SIGNAL(finished(QNetworkReply *)), this,
SLOT(finishedRequest(QNetworkReply *)));
// determine what range of tiles we can load
const int min_x = std::max(0, tile_x_ - blocks_);
const int min_y = std::max(0, tile_y_ - blocks_);
const int max_x = std::min(maxTiles(), tile_x_ + blocks_);
const int max_y = std::min(maxTiles(), tile_y_ + blocks_);
// initiate requests
for (int y = min_y; y <= max_y; y++) {
for (int x = min_x; x <= max_x; x++) {
const QUrl uri = uriForTile(x, y);
// send request
const QNetworkRequest request = QNetworkRequest(uri);
QNetworkReply *rep = qnam_->get(request);
emit initiatedRequest(request);
tiles_.push_back(MapTile(x, y, rep));
}
}
}
void TileLoader::start() {
// discard previous set of tiles and all pending requests
abort();
ROS_INFO("loading %d blocks around tile=(%d,%d)", blocks_, center_tile_x_, center_tile_y_ );
qnam_.reset( new QNetworkAccessManager(this) );
QObject::connect(qnam_.get(), SIGNAL(finished(QNetworkReply *)), this,
SLOT(finishedRequest(QNetworkReply *)));
// determine what range of tiles we can load
const int min_x = std::max(0, center_tile_x_ - blocks_);
const int min_y = std::max(0, center_tile_y_ - blocks_);
const int max_x = std::min(maxTiles(), center_tile_x_ + blocks_);
const int max_y = std::min(maxTiles(), center_tile_y_ + blocks_);
// initiate requests
for (int y = min_y; y <= max_y; y++) {
for (int x = min_x; x <= max_x; x++) {
// Generate filename
const QString full_path = cachedPathForTile(x, y, zoom_);
// Check if tile is already in the cache
QFile tile(full_path);
if (tile.exists()) {
QImage image(full_path);
tiles_.push_back(MapTile(x, y, zoom_, image));
} else {
const QUrl uri = uriForTile(x, y, zoom_);
// send request
const QNetworkRequest request = QNetworkRequest(uri);
QNetworkReply *rep = qnam_->get(request);
emit initiatedRequest(request);
tiles_.push_back(MapTile(x, y, zoom_, rep));
}
}
}
checkIfLoadingComplete();
}
