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I'v got a detail map for an event as PDF an made an openlayers slippy map with Maptiler. I now need to place markers at the position of gps/gsm-trackers, which store their coordinate on a server.

The map's north isn't at top and i need some kind of formula (projection?) to translate the gps coordinates to the coordinates of my map.

Is this somehow possible, e.g. via. 2 points where I know the coordinates in both systems?

I don't expect a finished solution but maybe you can give a hint where to start, I've no idea how to do this.

Example: GPS 48.26771, 16.36882 (somewhere in Vienna, Austria) in my projection is 0, 0

GPS 48.26673, 16.3696 is 100, 0

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For starters, can you provide an example of your coordinates, which projection are they in currently, and which projectio do you wish them to be in after conversion? –  CatchingMonkey Jun 13 '12 at 8:53
    
edited my question, please see example above –  stwagner Jun 13 '12 at 9:15
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1 Answer 1

The general approach is to georeference the image/PDF, perform a reprojection if necessary (will screw up labels though!) and only then create tiles and overlays.

For georeferencing, you can use QGIS georeferencer for example.

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thanks for the idea, but everything is based on the coordinate system starting with 0,0 on the left top. isn't it possible to translate the coordinates? –  stwagner Jun 13 '12 at 12:21
    
Depending on how the PDF map looks like it might be possible to find working transformation settings for scaling, translating and rotating. You can read up on the theory e.g. at plone.itc.nl/geometrics/Coordinate%20transformations/…. –  underdark Jun 14 '12 at 6:42
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