Merge pull request #622 from openmobilemaps/feature/epsg-url-template

Feature/epsg url template

CHANGELOG.md

@@ -1,5 +1,8 @@
 # Changelog for Open Mobile Maps
 
+## Version 2.2.0
+- Adds support for `{bbox-epsg-3857}` placeholder in URL template
+
 ## Version 2.1.0 (08.04.2024)
 - Adds dotted line style (line-dotted boolean and an optional skewFactor, defaulting to 1.0 and denoting the stretch factor)
 - Fixes style for short dashes

shared/public/Tiled2dMapVectorLayerConfig.h

@@ -32,6 +32,29 @@ class Tiled2dMapVectorLayerConfig : public Tiled2dMapLayerConfig {
 
     std::string getTileUrl(int32_t x, int32_t y, int32_t t, int32_t zoom) override {
         std::string url = sourceDescription->vectorUrl;
+        size_t epsg3857Index = url.find("{bbox-epsg-3857}", 0);
+        if (epsg3857Index != std::string::npos) {
+            const auto zoomLevelInfos = getDefaultEpsg3857ZoomLevels(zoom, zoom);
+            const Tiled2dMapZoomLevelInfo &zoomLevelInfo = zoomLevelInfos.at(0);
+            RectCoord layerBounds = zoomLevelInfo.bounds;
+            const double tileWidth = zoomLevelInfo.tileWidthLayerSystemUnits;
+
+            const bool leftToRight = layerBounds.topLeft.x < layerBounds.bottomRight.x;
+            const bool topToBottom = layerBounds.topLeft.y < layerBounds.bottomRight.y;
+            const double tileWidthAdj = leftToRight ? tileWidth : -tileWidth;
+            const double tileHeightAdj = topToBottom ? tileWidth : -tileWidth;
+
+            const double boundsLeft = layerBounds.topLeft.x;
+            const double boundsTop = layerBounds.topLeft.y;
+
+            const Coord topLeft = Coord(epsg3857Id, x * tileWidthAdj + boundsLeft, y * tileHeightAdj + boundsTop, 0);
+            const Coord bottomRight = Coord(epsg3857Id, topLeft.x + tileWidthAdj, topLeft.y + tileHeightAdj, 0);
+
+            std::string boxString = std::to_string(topLeft.x) + "," + std::to_string(bottomRight.y) + "," + std::to_string(bottomRight.x) + "," + std::to_string(topLeft.y);
+            url = url.replace(epsg3857Index, 16, boxString);
+            return url;
+
+        }
         size_t zoomIndex = url.find("{z}", 0);
         if (zoomIndex == std::string::npos) throw std::invalid_argument("Layer url \'" + url + "\' has no valid format!");
         url = url.replace(zoomIndex, 3, std::to_string(zoom));