Now multiple DEMS can be cached. The implemented solution is not fully...

Now multiple DEMS can be cached. The implemented solution is not fully satisfactory (a API change for all plugins would be required), but at least the core of it is implemented (in the Buffer class).

meteoio/GridsManager.cc

@@ -91,11 +91,11 @@ void GridsManager::readDEM(DEMObject& grid2D)
 	if (processing_level == IOUtils::raw){
 		iohandler.readDEM(grid2D);
 	} else {
-		if (buffer.get(grid2D))
+		if (buffer.get(grid2D, "/:DEM"))
 			return;
 
 		iohandler.readDEM(grid2D);
-		buffer.push(grid2D);
+		buffer.push(grid2D, "/:DEM");
 	}
 }
 

meteoio/dataClasses/Buffer.cc

@@ -226,7 +226,7 @@ const std::string MeteoBuffer::toString() const
 /********************************************************************************************/
 
 GridBuffer::GridBuffer(const size_t& in_max_grids) 
-           : dem_buffer(), mapBufferedGrids(), mapBufferedInfos(), IndexBufferedGrids(), max_grids(in_max_grids) 
+           : mapBufferedGrids(), mapBufferedDEMs(), mapBufferedInfos(), IndexBufferedGrids(), IndexBufferedDEMs(), max_grids(in_max_grids) 
 {}
 
 
@@ -266,22 +266,24 @@ bool GridBuffer::get(Grid2DObject& grid, const MeteoGrids::Parameters& parameter
 	return get(grid, grid_hash);
 }
 
-bool GridBuffer::get(DEMObject& grid) const
+bool GridBuffer::get(DEMObject& grid, const std::string& grid_hash) const
 {
-	if (max_grids==0) return false;
-	
-	if (!dem_buffer.empty()) {
-		//HACK: properly manage buffering multiple dems!
-		//already in buffer. If the update properties have changed,
-		//we copy the ones given in input and force the update of the object
+	if (IndexBufferedDEMs.empty())
+		return false;
+
+	const std::map<std::string, DEMObject>::const_iterator it = mapBufferedDEMs.find( grid_hash );
+	if (it != mapBufferedDEMs.end()) { //already in map
+		//properties of the passed dem
 		const DEMObject::update_type in_ppt = (DEMObject::update_type)grid.getUpdatePpt();
 		const DEMObject::slope_type in_slope_alg = (DEMObject::slope_type)grid.getDefaultAlgorithm();
 
-		grid = dem_buffer[0];
+		//get cached dem and its properties
+		grid = (*it).second;
 		const DEMObject::update_type buff_ppt = (DEMObject::update_type)grid.getUpdatePpt();
 		const DEMObject::slope_type buff_slope_alg = (DEMObject::slope_type)grid.getDefaultAlgorithm();
 
 		if (in_ppt!=buff_ppt || in_slope_alg!=buff_slope_alg) {
+			//if passed properties != cached properties -> set the returned one to the passed properties
 			grid.setDefaultAlgorithm(in_slope_alg);
 			grid.setUpdatePpt(in_ppt);
 			grid.update();
@@ -289,21 +291,23 @@ bool GridBuffer::get(DEMObject& grid) const
 
 		return true;
 	}
-	
+
 	return false;
 }
 
-void GridBuffer::push(const DEMObject& grid)
+void GridBuffer::push(const DEMObject& grid, const std::string& grid_hash)
 {
-	//HACK: properly manage buffering multiple dems!
-	//std::ostringstream grid_hash;
-	//grid_hash << dem_buffer[ii].llcorner.printLatLon() << " " << dem_buffer[ii].getNx() << "x" << dem_buffer[ii].getNy() << " @" << dem_buffer[ii].cellsize << "m";
 	if (max_grids==0) return;
-	
-	if (!dem_buffer.empty())
-		dem_buffer.clear();
-	
-	dem_buffer.push_back( grid );
+
+	if(IndexBufferedDEMs.size() >= max_grids) { //we need to remove the oldest grid
+		const string tmp_hash = IndexBufferedDEMs.front();
+		mapBufferedDEMs.erase( mapBufferedDEMs.find( tmp_hash ) );
+		//swap followed by pop_back is faster than erase()
+		swap( IndexBufferedDEMs.front(), IndexBufferedDEMs.back() );
+		IndexBufferedDEMs.pop_back();
+	}
+	mapBufferedDEMs[ grid_hash ] = grid;
+	IndexBufferedDEMs.push_back( grid_hash );
 }
 
 void GridBuffer::push(const Grid2DObject& grid, const std::string& grid_hash, const std::string& grid_info)
@@ -314,7 +318,7 @@ void GridBuffer::push(const Grid2DObject& grid, const std::string& grid_hash, co
 		const string tmp_hash = IndexBufferedGrids.front();
 		mapBufferedGrids.erase( mapBufferedGrids.find( tmp_hash ) );
 		mapBufferedInfos.erase( mapBufferedInfos.find( tmp_hash ) );
-		//IndexBufferedGrids.erase( IndexBufferedGrids.begin() );
+		//swap followed by pop_back is faster than erase()
 		swap( IndexBufferedGrids.front(), IndexBufferedGrids.back() );
 		IndexBufferedGrids.pop_back();
 	}
@@ -345,20 +349,17 @@ const std::string GridBuffer::toString() const
 	os << "Max buffered grids = " << max_grids << "\n";
 
 	//cache content
-	os << "Current buffer content (" << mapBufferedGrids.size() << " grids):\n";
-	std::map<std::string, Grid2DObject>::const_iterator it1;
-	for (it1=mapBufferedGrids.begin(); it1 != mapBufferedGrids.end(); ++it1){
-		os << setw(10) << "Grid " << it1->first << "\n";
+	os << "Cached grids: " << mapBufferedGrids.size() << "\n";
+	std::map<std::string, Grid2DObject>::const_iterator it_grid;
+	for (it_grid=mapBufferedGrids.begin(); it_grid != mapBufferedGrids.end(); ++it_grid){
+		os << setw(10) << "Grid " << it_grid->first << "\n";
 	}
 	
 	//dem buffer
-	if (!dem_buffer.empty()) {
-		os << "Dem buffer content (" << dem_buffer.size() << " grids):\n";
-		for (size_t ii=0; ii<dem_buffer.size(); ++ii){
-			std::ostringstream ss;
-			ss << dem_buffer[ii].llcorner.printLatLon() << " " << dem_buffer[ii].getNx() << "x" << dem_buffer[ii].getNy() << " @" << dem_buffer[ii].cellsize << "m";
-			os << setw(10) << "Dem " << ss.str() << "\n";
-		}
+	os << "Cached dems: " << mapBufferedDEMs.size() << "\n";
+	std::map<std::string, DEMObject>::const_iterator it_dem;
+	for (it_dem=mapBufferedDEMs.begin(); it_dem != mapBufferedDEMs.end(); ++it_dem){
+		os << setw(10) << "Dem " << it_dem->first << "\n";
 	}
 
 	os << "</GridBuffer>\n";

meteoio/dataClasses/Buffer.h

@@ -134,22 +134,23 @@ class GridBuffer {
 		
 		void setMaxGrids(const size_t& in_max_grids) {max_grids=in_max_grids;};
 		
-		bool get(DEMObject& grid) const;
+		bool get(DEMObject& grid, const std::string& grid_hash) const;
 		bool get(Grid2DObject& grid, const std::string& grid_hash) const;
 		bool get(Grid2DObject& grid, const std::string& grid_hash, std::string& grid_info) const;
 		bool get(Grid2DObject& grid, const MeteoGrids::Parameters& parameter, const Date& date) const;
 		
-		void push(const DEMObject& grid);
+		void push(const DEMObject& grid, const std::string& grid_hash);
 		void push(const Grid2DObject& grid, const std::string& grid_hash);
 		void push(const Grid2DObject& grid, const std::string& grid_hash, const std::string& grid_info);
 		void push(const Grid2DObject& grid, const MeteoGrids::Parameters& parameter, const Date& date);
 		
 		const std::string toString() const;
 	private:		
-		std::vector<DEMObject> dem_buffer;
 		std::map<std::string, Grid2DObject> mapBufferedGrids;  ///< Buffer interpolated grids
+		std::map<std::string, DEMObject> mapBufferedDEMs;  ///< Buffer interpolated grids
 		std::map<std::string, std::string> mapBufferedInfos; ///< Buffer interpolations info messages
 		std::vector<std::string> IndexBufferedGrids; // this is required in order to know which grid is the oldest one
+		std::vector<std::string> IndexBufferedDEMs; // this is required in order to know which grid is the oldest one
 		size_t max_grids; ///< How many grids to buffer (grids, dem, landuse and assimilation grids together)
 };