I want to get geo data as geojson for geojson tile layer requests in leaflet. I set up a geojson layer like this: https://github.com/glenrobertson/leaflet-tilelayer-geojson/

A php script answers requests and reads polygon geometries as geojson with ST_AsGeoJSON from postgreSQL.

Each request is mapped to those php file by an htaccess to geo.php.

I can see all requests in Google Chrome in developer tools on network tab. It looks like:


with following response:


Output is calculated by x,y and z as zoom. Those parameters are calculated and transformed by the following function:

function tileCoord2BBox($url)
    $parsed = explode("/",$url);

    $z = $parsed[3];
    $x = $parsed[4];
    $y = $parsed[5];

    $n = pow(2, $z);

    $lon1 = $x / $n * 360.0 - 180.0;
    $lat1 = rad2deg(atan(sinh(pi() * (1 - 2 * $y / $n))));

    $lon2 = ($x + 1) / $n * 360.0 - 180.0;
    $lat2 = rad2deg(atan(sinh(pi() * (1 - 2 * ($y + 1) / $n))));

    $bbox =  array();
    $bbox['lon1'] = $lon1;
    $bbox['lat1'] = $lat1;
    $bbox['lon2'] = $lon2;
    $bbox['lat2'] = $lat2;

    return $bbox;

Reference: http://wiki.openstreetmap.org/wiki/Slippy_map_tilenames

Those return values are used in sql statement defininig a bounding box which selects those polygons which are in that tile. Postgres returns geojson for resulting geometry.

I tested the responses with http://geojsonlint.com/ They all looks great.

But on leaflet map, I only see a partial polygon on only one tile. When I zoom or pan over leaflet map then another tile shows up with partial polygon.

In tilelayer.geojson.js on line 187 Chrome reports many errors with following output:

Uncaught TypeError: Cannot read property 'type' of undefined TileLayer.GeoJSON.js:187 L.TileLayer.GeoJSON.L.TileLayer.Ajax.extend.addTileData TileLayer.GeoJSON.js:187 L.TileLayer.GeoJSON.L.TileLayer.Ajax.extend._tileLoaded TileLayer.GeoJSON.js:246 (anonymous function)

It is reported on this line: https://github.com/glenrobertson/leaflet-tilelayer-geojson/blob/master/TileLayer.GeoJSON.js#L187

I think my output from server is ok. I will see a result on one tile and http://geojsonlint.com/ shows correctly that those data is valid for all the other requests. Also all requests have valid output.

What am I doing wrong? Why is it still showing an error even though all responses seem to be valid? If someone has a complete example with client and server side code using a geojson layer and with postgres or similiar, I really would appreciate that.

I do not know how I can solve my problem.

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