Visualize a subway map in SQL server 2012 spatial data based on the map of the subway. The map shall use geometry, traffic rail road as line object, station as point object and zon as polygon object.

In order to display the map, I need retrieve X, Y coordinate (cartesian coordinate system) and display it in the SQL server spatial data.

The question is:
How should I get X and Y coordination in every object from the map when you have the map as a paperwork or gif picture?

I have a feeling that I need a special application having cartesian coordinate system for the map. In the application (maybe same application as CAD) you have the map as a background and then you use the cursor to retrieve X and Y coordinate for every object. Then you have the data so you can use SQL server to picturize a map with data.
Maybe you have another solution.

Other Info
*Please take account that I do not want to use geography data.

*The X and Y data retrieve from the special application shall be enable to use in SQL server. In other word, same cartesian coordinate system.

*The Spatial reference system shall not be used.

enter image description here

  • And what does "I do not want to use geography data" mean? You don't want to work with Lat/Long to figure this problem out?
    – Taylor H.
    Feb 4 '13 at 14:16
  • You're right. In this context lat/long doesn't work. Sorry!
    – What'sUP
    Feb 4 '13 at 14:24
  • Are the unit vector lengths and the origin of the coordinate system arbitrary?
    – Jake
    Feb 4 '13 at 14:26
  • The X and Y will not be linked to spatial reference system because I be using a naturally cartesian in SQL server which means that it will not be linked to coordinate system like UTM, WSGR84 etc.
    – What'sUP
    Feb 4 '13 at 15:05

What you want is a process called 'Georeferencing'. It involves taking an image with no spatial reference (like the one you have) and placing it in space. This usually involves having several GPS points and matching them up to points on the map. You need at least 4 of these points. Check out this overview of Georeferencing posted in a recent thread. Credit to Sunil

In my experience this map would be extremely difficult to create an accurate georeferenced map from because it has been generalized. However, it might be possible to get the Lat/Long of the subway stations and match the map up that way. Check out this tutorial I made. It might help you figure out this process. You will definitely need some GIS software. If you don't have ArcGIS then QGIS is a more than capable alternative.


You can georeference the image above but don't forget that the map is highly stylised and the positions of the stations and indeed the coastline are not geographically correct.

  • I'm fully aware about it.
    – What'sUP
    Feb 4 '13 at 15:50

Why do you need to map this in a geographic information system, they aren't buit for this type of problem. Don't mistake this type of mapping for what GIS is. Adobe Illustrator or Inkscape (free) would be a better route, I think. You could georeference but the results would be mostly meaningless as what are the points that you need to match that match real world objects. What is the purpose here of storing in a sql interface with a lat lon that is not geographic? You can backend both Illustrator and Inkscape with sql for specific purposes. Here is a reference from a google search "FormObject - Inkscape Wikiwiki.inkscape.org/wiki/index.php/FormObjectCached - Jun 24, 2004 – This should also be usable for implementing SQL tables for diagramming purposes." http://wiki.inkscape.org/wiki/index.php/FormObject

  • Well, I'm not storing lat/lon. I'm storing x and y in relation to geometry.
    – What'sUP
    Feb 4 '13 at 21:01
  • This answer is the closest one but unfortunately I still haven't retrieved the right solution to my purpose. Thank you for your help.
    – What'sUP
    Feb 5 '13 at 13:47
  • I was curious to what specificaly are you trying to achieve with x,y?
    – lewis
    Feb 5 '13 at 14:08
  • To draw a picture based on vector point
    – What'sUP
    Feb 5 '13 at 14:10
  • Inkscape, and I assume Illustrator, have a cartesian cordinate system, use vectors and have vector and point tools, and do a good job of visual display and styling and are aften used by map makers and cartographers for the very purpose of making system maps.
    – lewis
    Feb 5 '13 at 14:42

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