[GIS] google maps tiling scheme index grid

mapstilecachetiling

I have a need to cut tiles from a raster with bounds that result in no partially filled tiles at a particular zoom level (no transparency or black/white areas). First thought was to overlay an index grid so I could see how to cut the raster. Is it possible to find shapefile or other description of the tiling grid for google maps or other tiling schemes.

Also interested in other idea for achieving this goal. One is to simply programmatically discard tiles with empty areas after the fact. Interested in other suggestions as well.

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This page has the information you want http://www.maptiler.org/google-maps-coordinates-tile-bounds-projection/ and python script for programatically finding tile bounds.

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TileCache: Understanding Its Tiling Scheme and Documentation

answer to my comment(this code is for my tms scheme and you can adapt it to your need):

var originShift = 2 * Math.PI * 6378137 / 2.0;
var initialResolution = 2 * Math.PI * 6378137 / 256; //tilesize

var lon = 10;
var lat = 20;

var mx = lon * originShift / 180.0;
var my = Math.log(Math.tan((90 + lat) * Math.PI / 360.0)) / (Math.PI / 180.0);

my = my * originShift / 180.0;

//MetersToPixel(mx, my, zooma)
var res = initialResolution / (Math.pow(2, zooma));
var px = (mx + originShift) / res;
var py = (my + originShift) / res;

//PixelsToTile(px, py)
var tx = Math.ceil(px / parseFloat(256)) - 1;
var ty = Math.ceil(py / parseFloat(256)) - 1;

tx and ty will give you to tms result as lanlot. if you want to know equivalent to google map, you can calculate the Y file name (Math.pow(2, zoom) - 1) - ty

Google Tile Mechanism: x/y/z.jpg

TMS Tile Mechanism: z/y/x.jpg

i hope it helps you...

[GIS] Google maps, download entire province/region from google maps

GoogleMaps is now offering 'off-line' mode, so you can do this without any GIS or programming at all. The trick is you'll need Android Ice Cream Sandwich or Jelly Bean: A new Google Maps app for smartphone and tablets

The offline maps feature for Android is also no longer available. Instead we’ve created a new way for you to access maps offline by simply entering “OK Maps” into the search box when viewing the area you want for later. Finally, My Maps functionality is not supported in this release but will return to future versions of the app. People who want to create powerful custom maps can still do so with Maps Engine Lite on desktop.

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Related Solutions

TileCache: Understanding Its Tiling Scheme and Documentation

[GIS] Google maps, download entire province/region from google maps

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