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@walkermatt
Created July 2, 2012 18:25
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Leaflet Map using Proj4Leaflet to display a projected TMS base map from MapProxy
// Bounding box of our TMS that define our area of interest
var bbox = [-600000, -300000, 1300000, 1600000];
// Resolutions of our TMS that the tiles will be displayed at calculated so
// that at resolution 0 the bounds fit one 256x256 tile: (maxx - minx)/256
var res = [7421.875, 3710.9375, 1855.46875, 927.734375];
// Define the Proj4Leaflet coordinate reference system base on British National Grid
var crs = L.CRS.proj4js(
'EPSG:27700',
'+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 +ellps=airy +datum=OSGB36 +units=m +no_defs',
new L.Transformation(1, -bbox[0], -1, bbox[3])
);
// Define a scale custom function to calculate
// the scale based on the current zoom. Prior to
// v0.4 the scale function was a member of the map
crs.scale = function(zoom) {
return 1 / res[zoom];
};
var map = new L.Map('map', {
crs: crs,
continuousWorld: true,
worldCopyJump: false
});
var mapUrl = 'http://my.mapproxy.server/tms/1.0.0/layername_EPSG27700/{z}/{x}/{y}.png';
var tilelayer = new L.TileLayer(mapUrl, {
tms: true,
maxZoom: res.length - 1,
minZoom: 0,
continuousWorld: true,
attribution: 'Copyright 2012'
});
map.addLayer(tilelayer);
// Centre on London zoom to the maximum extent
map.setView(new L.LatLng(51.33129296535873, -0.6680291327536106), 0);
@walkermatt
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JavaScript required to create a Leaflet map configured with a British National Grid projection and a TMS backed layer provided by MapProxy using Proj4Leaflet to enable the use of a custom projection.

Based on the Proj4Leaflet example Thanks to @perliedman and @bartvde for their help with the original and the post Leaflet v0.4 update.

Things of note:

  • I think that Leaflet requires that each resolution must be half of the preceeding resolution.
  • You can get the appropriate Proj4 coordinate system definition from the awesome spatialreference.org, for instance the definition used above can be found here: http://spatialreference.org/ref/epsg/27700/ then click on Proj4.
  • Prior to Leaflet v0.4 TileLayer had a scheme property that had to be set to tms, post v0.4 you set the tms property to true.
  • In my previous example I think I messed up the Transformation parameters. The current version uses: 1, -minx, -1, maxy. The transformation is used when going from projected coordiates to grid coordinates, further detail in @perliedman's blog post: http://blog.kartena.se/local-projections-in-a-world-of-spherical-mercator/.
  • Coordinates are still defined in LatLong.
  • You should be able to determine everything required to set up a TMS layer from spatialreference.org together with the GetCapabilites document which for the example MapProxy server used above would be available at: http://my.mapproxy.server/tms/1.0.0/layername_EPSG27700

@pkorac
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pkorac commented Mar 22, 2013

Matt thx very much for the gist.
Have you got a full example working anywhere?
I'm having trouble understanding which js in proje4leaflet's example does what.

Peter

@edwhittaker
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Thanks Matt!

I was just having a play with Leaflet and a WMS in EPSG27700, your code has got me up and going.

Cheers,

Ed

@tomchadwin
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From memory, the projection might not be quite right (offset by ca 200m). Try removing the DATUM declaration, and replace with a correct towgs84:

+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 +ellps=airy +towgs84=446.448,-125.157,542.06,0.15,0.247,0.842,-20.489 +units=m +no_defs

@abersh
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abersh commented Jan 13, 2016

how to overlay maps on openlayers API by tms server I render maps by mapnik but doesn't dysplay on openlayers API
please help any one !!!

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