// WMTS Layer Geoportail (http://ol3js.org/en/master/examples/wmts.html)
/**
* @constructor IGN's Geoportail WMTS layer definition
* @extends {ol.source.WMTS}
* @param {String=} key API key.
* @param {String=} layer Layer name.
* @param {olx.source.OSMOptions=} options WMTS options.
* @todo 
*/
ol.source.Geoportail = function(key, layer, options)
{  if (!options) options={};
  var matrixIds = new Array();
  var resolutions = new Array();
  var size = ol.extent.getWidth(ol.proj.get('EPSG:3857').getExtent()) / 256;
  for (var z=0; z <= (options.maxZoom ? options.maxZoom:18) ; z++) 
  {  matrixIds[z] = z ; 
    resolutions[z] = size / Math.pow(2, z)
  }
  var attr = [ ol.source.Geoportail.prototype.attribution ];
  if (options.attributions) attr.push(options.attributions);
  ol.source.WMTS.call (this, 
    {  url: "http://wxs.ign.fr/" + key + "/wmts",
      layer: layer,
      matrixSet: "PM",
      format: options.format ? options.format:"image/jpeg",
      projection: "EPSG:3857",
      tileGrid: new ol.tilegrid.WMTS
      ({  origin: [-20037508, 20037508],
        resolutions: resolutions,
        matrixIds: matrixIds
      }),
      style: options.style ? options.style:"normal",
      attributions: attr
    });  
};
ol.inherits (ol.source.Geoportail, ol.source.WMTS);
// Attribution standard
ol.source.Geoportail.prototype.attribution = new ol.Attribution
    ({  html: '<a href="http://www.geoportail.gouv.fr/">Géoportail</a> &copy; <a href="http://www.ign.fr/">IGN-France</a>'
    });
/** */
// La carte
var map = new ol.Map
({  target: 'map',
  renderer: ["canvas"],  /* ["webgl", "canvas", "dom"] */
  view: new ol.View
  ({  zoom: 7,
    center: [288074, 6247982]
  }),
  controls: ol.control.defaults().extend
  ([  new ol.control.FullScreen()
  ]),
  layers: [new ol.layer.Tile(
    {  source: new ol.source.Geoportail(MA_CLE, "GEOGRAPHICALGRIDSYSTEMS.MAPS")
    })]
});