fixes #1244 #1258

rspatial · Aug 26, 2023 · 8fb1244 · kadyb · Aug 27, 2023 · 8fb1244
1 parent 96de18d
commit 8fb1244
Show file tree

Hide file tree

Showing 4 changed files with 31 additions and 22 deletions.
diff --git a/R/tiles.R b/R/tiles.R
@@ -45,14 +45,26 @@ setMethod("makeTiles", signature(x="SpatRaster"),
 
 
 setMethod("vrt", signature(x="character"),
-	function(x, filename="", options=NULL, overwrite=FALSE) {
+	function(x, filename="", options=NULL, overwrite=FALSE, set_names=FALSE, return_filename=FALSE) {
 		opt <- spatOptions(filename, overwrite=overwrite)
 		r <- rast()
 		if (is.null(options)) {
 			options=""[0]
 		} 
-		r@pnt <- r@pnt$make_vrt(x, options, opt)
+		f <- r@pnt$make_vrt(x, options, opt)
 		messages(r, "vrt")
+		if (set_names) {
+			v <- readLines(f)
+			nms <- names(rast(x[1]))
+			i <- grep("band=", v)
+			if (length(i) == length(nms)) {
+				nms <- paste0("<Description>", nms, "</Description>")
+				v[i] <- paste(v[i], nms)
+				writeLines(v, f)
+			}
+		}
+		if (return_filename) return(f)
+		rast(f)
 	}
 )
 
diff --git a/man/vrt.Rd b/man/vrt.Rd
@@ -9,18 +9,21 @@
 \title{Virtual Raster Dataset}
 
 \description{ 
-Create a Virtual Raster Dataset (VRT) from a collection of file-based raster datasets (tiles). 
+Create a Virtual Raster Dataset (VRT) from a collection of file-based raster datasets (tiles). See 
+\href{https://gdal.org/programs/gdalbuildvrt.html}{gdalbuildvrt} for details.
 }
 
 \usage{
-\S4method{vrt}{character}(x, filename="", options=NULL, overwrite=FALSE)
+\S4method{vrt}{character}(x, filename="", options=NULL, overwrite=FALSE, set_names=FALSE, return_filename=FALSE)
 }
 
 \arguments{
   \item{x}{character. Filenames of raster "tiles". See \code{\link{tiles}}}
   \item{filename}{character. Output VRT filename}  
   \item{options}{character. All arguments as separate vector elements. Options as for \href{https://gdal.org/programs/gdalbuildvrt.html}{gdalbuildvrt}}
   \item{overwrite}{logical. Should \code{filename} be overwritten if it exists?}
+  \item{set_names}{logical. Add the layer names of the first tile to the vrt?}
+  \item{return_filename}{logical. If \code{TRUE} the filename is returned, otherwise a SpatRaster is retunred}  
 }
 
 \value{

diff --git a/src/gdalio.cpp b/src/gdalio.cpp
@@ -311,10 +311,9 @@ std::vector<std::vector<std::string>> sdinfo(std::string fname) {
 
 #if GDAL_VERSION_MAJOR <= 2 && GDAL_VERSION_MINOR < 1
 
-SpatRaster SpatRaster::make_vrt(std::vector<std::string> filenames, std::vector<std::string> options, SpatOptions &opt) {
-	SpatRaster out;
-	out.setError( "GDAL version >= 2.1 required for vrt");
-	return out;
+std::string SpatRaster::make_vrt(std::vector<std::string> filenames, std::vector<std::string> options, SpatOptions &opt) {
+	setError( "GDAL version >= 2.1 required for vrt");
+	return("");
 }
 
 
@@ -328,15 +327,14 @@ std::string gdalinfo(std::string filename, std::vector<std::string> options, std
 
 # include "gdal_utils.h" // requires >= 2.1
 
-SpatRaster SpatRaster::make_vrt(std::vector<std::string> filenames, std::vector<std::string> options, SpatOptions &opt) {
+std::string SpatRaster::make_vrt(std::vector<std::string> filenames, std::vector<std::string> options, SpatOptions &opt) {
 
-	SpatRaster out;
 	std::string outfile = opt.get_filename();
 	if (outfile.empty()) {
 		outfile = tempFile(opt.get_tempdir(), opt.pid, ".vrt");
 	} else if (file_exists(outfile) && (!opt.get_overwrite())) {
-		out.setError("output file exists. You can use 'overwrite=TRUE' to overwrite it");
-		return(out);
+		setError("output file exists. You can use 'overwrite=TRUE' to overwrite it");
+		return("");
 	}
 
 /*
@@ -377,9 +375,9 @@ SpatRaster SpatRaster::make_vrt(std::vector<std::string> filenames, std::vector<
 	std::vector <char *> vops = string_to_charpnt(options);
 	GDALBuildVRTOptions* vrtops = GDALBuildVRTOptionsNew(vops.data(), NULL);
 	if (vrtops == NULL) {
-		out.setError("options error");
+		setError("options error");
 		CSLDestroy( names );
-		return(out);
+		return("");
 	}
 	int pbUsageError;
 //	GDALDataset *ds = (GDALDataset *) GDALBuildVRT(outfile.c_str(), tiles.size(), (GDALDatasetH *) tiles.data(), nullptr, vrtops, &pbUsageError);
@@ -391,15 +389,11 @@ SpatRaster SpatRaster::make_vrt(std::vector<std::string> filenames, std::vector<
 
 	//for (size_t i= 0; i<tiles.size(); i++) GDALClose(tiles[i]);
 	if(ds == NULL )  {
-		out.setError("cannot create vrt. Error #"+ std::to_string(pbUsageError));
-		return out;
+		setError("cannot create vrt. Error #"+ std::to_string(pbUsageError));
+		return("");
 	}
 	GDALClose(ds);
-	if (!out.constructFromFile(outfile, {-1}, {""}, {}, {})) {
-		out.setError("cannot open created vrt");
-		return out;
-	}
-	return out;
+	return(outfile);
 }
 
 

diff --git a/src/spatRaster.h b/src/spatRaster.h
@@ -492,7 +492,7 @@ class SpatRaster {
 		//bool writeValues2(std::vector<std::vector<double>> &vals, size_t startrow, size_t nrows);
 		bool writeStop();
 		bool writeHDR(std::string filename);
-		SpatRaster make_vrt(std::vector<std::string> filenames, std::vector<std::string> options, SpatOptions &opt);
+		std::string make_vrt(std::vector<std::string> filenames, std::vector<std::string> options, SpatOptions &opt);
 		bool write_aux_json(std::string filename);
 
 		//bool writeStartGDAL(std::string filename, std::string driver, std::string datatype, bool overwrite, SpatOptions &opt);