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I'm relatively new to using a GIS.

I've been wondering how could I determine tile(s) on a selected area/point at a specified zoom level?

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  • 1
    what exactly are you trying to achieve? Why do you want the width and height at a particular zoom level? Jul 9, 2014 at 8:03
  • i'm going to do a map tile downloader. I've read about bing map tile system wherein you can get the tiles that will be downloaded on a selected area/point.
    – Minadale
    Jul 9, 2014 at 8:07
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    So basically you are asking which tiles will cover your area? If so I'll suggest that you edit your question to clarify this. Jul 9, 2014 at 8:09
  • msdn.microsoft.com/en-us/library/bb259689.aspx This is the Bing map's tile system. You can reference.
    – luqinghui
    Oct 7, 2016 at 10:36
  • This appears to be a comment to the posted answer, rather than an answer itself.
    – nmtoken
    Oct 7, 2016 at 12:01

1 Answer 1

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Bing Maps, Google Maps, OpenStreetMap and others use a Tiling scheme which has the following properties:

  • Tiles are 256 × 256 pixel PNG files
  • Each zoom level is a directory, each column is a subdirectory, and each tile in that column is a file
  • Filename(url) format is /zoom/x/y.png

This has been described in detail on MSDN as well as the OSM wiki

Both these pages contain code which shows how you can get the tile name (i.e. the x & the y for each tile), but the pseudo code is as follows:

n = 2 ^ zoom
xtile = n * ((lon_deg + 180) / 360)
ytile = n * (1 - (log(tan(lat_rad) + sec(lat_rad)) / π)) / 2

You can use this code to get the tilenames for your Area of Interest, and download the tiles yourself, or you can use a GUI software like Mobile Atlas Cache which can download these tiles for you.

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