What is the tiling scheme of TileCache?

Question

I am using TileCache from MetaCarta to create tiles for a WMS service. It creates a tile with an URL like http://example.com/tiles/Admin/06/000/000/357/000/000/158.png.

I am trying to understand how to start from Map Coordinates, and get the appropriate tile.

I am looking for some documentation which explains the Folder structure/hierarchy of the server cache directory

Answer 1

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...

Answer 2

Not to be snarky, but just read the source.