[OSM-talk] "scale" a ShapeFile in Y-direction?

[Juan Lucas Dominguez Rubio]

Hi:

I'm curious about that shapefile that needs some stretching. Assuming its name is filename.shp, try to type this:

ogrinfo -geom=NO filename.shp filename

what is the output?

Regards,
Juan Lucas


________________________________

		


		Hello Frederik,
		
		thanks for your hint. Yes, i know about projections.  Actually, i reprojected
		the rester images of "blue marble" from a form of WGS84 to Mercaator
		with an own program.
		
		But as i've heard it, world_boundaries_m is "defect".  But as an overlay
		to represent the boundaries it would be ok.  If that information was a
		misunderstanding and could be fixed with the right projection that would be
		awesome.
		
		If i use shoreline_300 instead, the projection is perfectly fine, but if you
		try to render it _not_filled_ with a LineSymbolizer instead of a
		PolygonSymbolizer, you get some disturbing "plates".  But the projection
		is fine.
		
		A ShapeFile contains the "source SRS" inside it, right?  When rendering
		world_boundaries_m and shoreline_300 i used the same "target SRS".
		But the result leads to different positions on the final map.
		
		Does that mean that world_boundaries_m is defect?
		
		Is there a way to "fix" it somehow?  Or would scaling be possible?
		
		
		Best regards,
		Torsten.
		
		
		> Hi,
		>
		> Torsten Mohr wrote:
		> > I have a ShapeFile that seems to be incorrect, scaling it in Y-direction
		> > could make it fit the background.
		>
		> Do you have a basic understanding of coordinate projections? If not,
		> you'd be well advised to spend a few hours reading on the subject (start
		> with Wikipedia, take it from there).
		>
		> You need to find out which projection your shapefile is in, and then set
		> the correct one in your map file, and things are likely to work. Simply
		> stretching the data from the shapefile is very unlikely to yield the
		> desired results - you will probably find that the stretch factor that
		> makes Iceland and the Equator fit will still have France out of place.
		>
		> Bye
		> Frederik
		
		
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