R/writeStartStop.R

In rspatial/raster: Geographic Data Analysis and Modeling

# Author: Robert J. Hijmans
# Date :  September 2009
# Version 0.9
# Licence GPL v3



setMethod("writeStart", signature(x="RasterLayer", filename="character"), 
function(x, filename, options=NULL, format, prj=FALSE, ...) {

	if (trim(filename) == "") { 
		filename <- rasterTmpFile() 
	}
	filename <- .fullFilename(filename, expand=TRUE)
	if (!file.exists(dirname(filename))) {
		stop("Attempting to write a file to a path that does not exist:\n  ", dirname(filename))
	}
	
	filetype <- .filetype(format=format, filename=filename)
	filename <- .getExtension(filename, filetype)
	if (filetype=="ascii") { 
		x <- .startAsciiWriting(x, filename, ...)
	} else if ( filetype %in% .nativeDrivers() ) { 
		x <- .startRasterWriting(x, filename, format=filetype, ...)
	} else if ( filetype == "CDF" ) { 
		x <- .startWriteCDF(x, filename, ...)
#	} else if ( filetype == "big.matrix" ) { 
#		x <- .startBigMatrixWriting(x, filename, ...)
	} else {
		x <- .startGDALwriting(x, filename, gdal=options, format=filetype, ...)
	}		
	
	if (prj) {
		wk <- wkt(x)
		if (wk != "") {
			writeLines(wk, extension(filename, "prj") )
		}
	}
	return(x)
})


setMethod("writeStart", signature(x="RasterBrick", filename="character"), 
function(x, filename, options=NULL, format, prj=FALSE, ...) {

	if (trim(filename) == "") { 
		filename <- rasterTmpFile() 
	}
	filename <- .fullFilename(filename, expand=TRUE)
	filetype <- .filetype(format=format, filename=filename)
	filename <- .getExtension(filename, filetype)
	
	if (filetype=="ascii") { 
		stop("ARC-ASCII files cannot contain multiple layers") 
	}
	native <- filetype %in% c(.nativeDrivers(), "ascii")
	if (native) { 
		x <- .startRasterWriting(x, filename, format=filetype, ...) 
	} else if ( filetype == "CDF" ) { 
		x <- .startWriteCDF(x, filename, ...)
#	} else if ( filetype == "big.matrix" ) { 
#		x <- .startBigMatrixWriting(x, filename, ...)
	} else {
		x <- .startGDALwriting(x, filename, gdal=options, format=filetype, ...) 
	}
	
	if (prj) {
		crs <-.getCRS(x)
		if (!is.na(crs)) {
			writeLines(wkt(x), extension(filename, "prj") )
		}
	}	
	
	return(x)
})


setMethod("writeStop", signature(x="RasterLayer"), 
	function(x) {
		driver <- x@file@driver
		if ( driver %in% .nativeDrivers() ) { 
			return( .stopRasterWriting(x) )
#		} else if ( driver == "big.matrix" ) { 
#			return( .stopBigMatrixWriting(x) )
		} else if ( driver == "ascii" ) { 
			return( .stopAsciiWriting(x) )
		} else if ( driver == "netcdf" ) { 
			return( .stopWriteCDF(x) )
		} else {
			return( .stopGDALwriting(x) )
		}
	}
)

setMethod("writeStop", signature(x="RasterBrick"), 
	function(x) {
		driver <- x@file@driver
		if (driver  %in% .nativeDrivers()) { 
			return( .stopRasterWriting(x) )
		} else if ( driver == "netcdf" ) { 
			return( .stopWriteCDF(x) )
#		} else if ( driver == "big.matrix" ) { 
#			return( .stopBigMatrixWriting(x) )
		} else {
			return( .stopGDALwriting(x) )
		}
	}
)