[Liblas-devel] Bug?: problem copying file with offset

[Peder Axensten]

I have a las-file with non-zero offsets (attached below).

If I used the code below to copy this file to a las-file I "lose" the offset. 
However, if I copy to a compressed laz-file all is well.
If I add a line printing the coordinates, they look normal in both cases (but still lose their offset in the las-case).

The first plots in the las-file becomes:
-3366.35,749.70,-62.21
-3366.34,750.40,-60.36
-3366.46,751.90,-62.03

Whereas in the laz-file they (correctly) are: 
419059.89,6483734.30,106.79
419059.89,6483734.37,106.97
419059.88,6483734.52,106.81

Here is the code (compress_file(out) returns true if the file extension is 'laz'): 
	std::size_t copy (
		const std::vector< std::string > & in,
		const std::string & out
	) {
		std::size_t					count = 0;
		try {
			std::ofstream			ofs( out.c_str(), std::ios::out | std::ios::binary );
			liblas::Header			header;
			header.SetCompressed( compress_file( out ) );
			liblas::Writer			writer( ofs, header );
			
			for( std::size_t i=0; i<in.size(); i++ ) {
				std::ifstream			ifs( in[i].c_str(), std::ios::in | std::ios::binary );
				liblas::ReaderFactory	rf;
				liblas::Reader			reader = rf.CreateWithStream( ifs );
		
				while( reader.ReadNextPoint() ) {
					++count;
					writer.WritePoint( reader.GetPoint() );
				}
			}
		} catch (std::exception const& e) {
			std::cerr << "Error: " << e.what() << std::endl;
		}
		return( count );
	}


Here is the las-file:

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Have I misunderstood something?
Any help appreciated!

Best regards,

Peder Axensten
Research engineer

Swedish University of Agricultural Sciences
Dept. of Forest Resource Management
Forest Remote Sensing
Skogmarksgränd
se-90183 Umeå
Sweden

Phone: +46-90-786.8500
http://www.srh.slu.se/rsl