version 2.21.1

Map download API
mapviewer download feature

libs/map/mapview.cpp

@@ -7,8 +7,10 @@
 
 #include <QGraphicsPixmapItem>
 #include <QGraphicsScene>
+#include <QMetaMethod>
 #include <QPainter>
 #include <QPixmap>
+#include <QProgressDialog>
 #include <QScrollBar>
 #include <QWheelEvent>
 
@@ -19,7 +21,9 @@ MapView::MapView(QWidget * parent): QWidget(parent) {
 	downloader = new OSMDownloader(this);
 	cache      = new OSMTileCache(this);
 	setMouseTracking(true);
-	connect(cache, &OSMTileCache::tileReady, this, [this]() { drawBackground(); });
+	connect(cache, &OSMTileCache::tileReady, this, [this]() {
+		if (!is_downloading) drawBackground();
+	});
 	int size = 16;
 	QPixmap px(QSize(size, size) * 2);
 	QPainter p(&px);
@@ -77,6 +81,88 @@ void MapView::setZoom(double z) {
 }
 
 
+QString MapView::cachePath() const {
+	return cache->cacheRoot();
+}
+
+
+void MapView::setCachePath(const QString & p) {
+	cache->setCacheRoot(p);
+	drawBackground();
+}
+
+
+void collectDownloadIndeces(QQueue<OSM::TileIndex> & indeces, OSM::TileIndex index, int target_zoom_level) {
+	indeces << index;
+	if (index.z >= target_zoom_level) return;
+	int z = index.z + 1;
+	int x = index.x * 2;
+	int y = index.y * 2;
+	for (int i = 0; i < 2; ++i) {
+		for (int j = 0; j < 2; ++j) {
+			collectDownloadIndeces(indeces, (OSM::TileIndex){z, x + i, y + j}, target_zoom_level);
+		}
+	}
+}
+
+
+void MapView::downloadCurrentView(int target_zoom_level) {
+	int sx            = qMax(0, (int)floor(view_rect.left() * tiles_side));
+	int sy            = qMax(0, (int)floor(view_rect.top() * tiles_side));
+	int ex            = qMin(tiles_side, (int)ceil(view_rect.right() * tiles_side));
+	int ey            = qMin(tiles_side, (int)ceil(view_rect.bottom() * tiles_side));
+	target_zoom_level = qMin(target_zoom_level, max_level);
+	QQueue<OSM::TileIndex> indeces;
+	for (int ix = sx; ix < ex; ++ix) {
+		for (int iy = sy; iy < ey; ++iy) {
+			collectDownloadIndeces(indeces, (OSM::TileIndex){zoom_level, ix, iy}, target_zoom_level);
+		}
+	}
+	if (indeces.size() < 4) return;
+	QProgressDialog dialog;
+	dialog.setWindowTitle(tr("MapView"));
+	dialog.setLabelText(tr("Downloading ..."));
+	dialog.setCancelButtonText(tr("Cancel"));
+	dialog.setMaximum(indeces.size());
+	dialog.setValue(0);
+	downloader->clearQueue();
+	std::atomic_int value(0);
+	auto conn = connect(
+		downloader,
+		&OSMDownloader::tileDone,
+		this,
+		[this, &dialog, &indeces, &value]() {
+			// qDebug() << "done";
+			value++;
+			int cv = value;
+			dialog.setValue(cv);
+			if (indeces.isEmpty())
+				dialog.cancel();
+			else {
+				downloader->queueTile(indeces.dequeue(), true);
+			}
+		},
+		Qt::DirectConnection);
+	connect(&dialog, &QProgressDialog::canceled, this, [this, &dialog]() {
+		dialog.cancel();
+		downloader->clearQueue();
+	});
+	is_downloading = true;
+	for (int i = 0; i < 1; ++i)
+		downloader->queueTile(indeces.dequeue());
+	// dialog.exec();
+	dialog.setModal(true);
+	dialog.show();
+	while (!dialog.isHidden()) {
+		QThread::msleep(1);
+		QApplication::processEvents();
+	}
+	disconnect(conn);
+	is_downloading = false;
+	drawBackground();
+}
+
+
 void MapView::mousePressEvent(QMouseEvent * e) {
 	is_pan           = false;
 	press_point      = e->pos();