Perform pruning of polygons only at zoom level 14

systemed · May 4, 2021 · 9dada2f · 9dada2f
1 parent e13e9d5
commit 9dada2f
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Showing 3 changed files with 13 additions and 7 deletions.
diff --git a/include/output_object.h b/include/output_object.h
@@ -120,7 +120,7 @@ static inline void intrusive_ptr_release(OutputObject *oo) {
  * Returns a boost::variant -
  *	 POLYGON->MultiPolygon, CENTROID->Point, LINESTRING->MultiLinestring
  */
-Geometry buildWayGeometry(OSMStore &osmStore, OutputObject const &oo, const TileBbox &bbox);
+Geometry buildWayGeometry(OSMStore &osmStore, OutputObject const &oo, const TileBbox &bbox, unsigned int zoom_level);
 
 //\brief Build a node geometry
 LatpLon buildNodeGeometry(OSMStore &osmStore, OutputObject const &oo, const TileBbox &bbox);

diff --git a/src/output_object.cpp b/src/output_object.cpp
@@ -111,7 +111,7 @@ Ring ReduceRing(Ring const &input, Box const &clippingBox, CheckLine checkline)
 	return result;
 }
 
-Geometry buildWayGeometry(OSMStore &osmStore, OutputObject const &oo, const TileBbox &bbox) 
+Geometry buildWayGeometry(OSMStore &osmStore, OutputObject const &oo, const TileBbox &bbox, unsigned int zoom) 
 {
 	switch(oo.geomType) {
 		case OutputGeometryType::POINT:
@@ -159,6 +159,12 @@ Geometry buildWayGeometry(OSMStore &osmStore, OutputObject const &oo, const Tile
 			geom::convert(bbox.clippingBox, clippingPolygon);
 			if (!geom::intersects(input, clippingPolygon)) { return MultiPolygon(); }
 
+			if(zoom < 14) {
+				MultiPolygon mp;
+				geom::intersection(input, clippingPolygon, mp);
+				return mp;
+			}
+
 			MultiPolygon mp;
 			Polygon extendPolygon;
 			geom::convert(bbox.getExtendBox(), extendPolygon);

diff --git a/src/tile_worker.cpp b/src/tile_worker.cpp
@@ -62,7 +62,7 @@ void ReorderMultiLinestring(MultiLinestring &input, MultiLinestring &output) {
 
 template <typename T>
 void CheckNextObjectAndMerge(OSMStore &osmStore, OutputObjectsConstIt &jt, OutputObjectsConstIt ooSameLayerEnd, 
-	const TileBbox &bbox, T &g) {
+	const TileBbox &bbox, unsigned int zoom, T &g) {
 
 	// If a object is a linestring/polygon that is followed by
 	// other linestrings/polygons with the same attributes,
@@ -81,7 +81,7 @@ void CheckNextObjectAndMerge(OSMStore &osmStore, OutputObjectsConstIt &jt, Outpu
 		else ooNext.reset();
 
 		try {
-			T to_merge = boost::get<T>(buildWayGeometry(osmStore, *oo, bbox));
+			T to_merge = boost::get<T>(buildWayGeometry(osmStore, *oo, bbox, zoom));
 			T output;
 			geom::union_(g, to_merge, output);
 			g = move(output);
@@ -114,7 +114,7 @@ void ProcessObjects(OSMStore &osmStore, OutputObjectsConstIt ooSameLayerBegin, O
 		} else {
 			Geometry g;
 			try {
-				g = buildWayGeometry(osmStore, *oo, bbox);
+				g = buildWayGeometry(osmStore, *oo, bbox, zoom);
 			} catch (std::out_of_range &err) {
 				if (verbose) cerr << "Error while processing geometry " << oo->geomType << "," << oo->objectID <<"," << err.what() << endl;
 				continue;
@@ -126,13 +126,13 @@ void ProcessObjects(OSMStore &osmStore, OutputObjectsConstIt ooSameLayerBegin, O
 
 			//This may increment the jt iterator
 			if (oo->geomType == OutputGeometryType::LINESTRING && zoom < sharedData.config.combineBelow) {
-				CheckNextObjectAndMerge(osmStore, jt, ooSameLayerEnd, bbox, boost::get<MultiLinestring>(g));
+				CheckNextObjectAndMerge(osmStore, jt, ooSameLayerEnd, bbox, zoom, boost::get<MultiLinestring>(g));
 				MultiLinestring reordered;
 				ReorderMultiLinestring(boost::get<MultiLinestring>(g), reordered);
 				g = move(reordered);
 				oo = *jt;
 			} else if (oo->geomType == OutputGeometryType::POLYGON && combinePolygons) {
-				CheckNextObjectAndMerge(osmStore, jt, ooSameLayerEnd, bbox, boost::get<MultiPolygon>(g));
+				CheckNextObjectAndMerge(osmStore, jt, ooSameLayerEnd, bbox, zoom, boost::get<MultiPolygon>(g));
 				oo = *jt;
 			}