Files
openlayers/examples/epsg-4326.js

57 lines
1.6 KiB
JavaScript

goog.require('goog.debug.Console');
goog.require('goog.debug.Logger');
goog.require('goog.debug.Logger.Level');
goog.require('ol.Collection');
goog.require('ol.Coordinate');
goog.require('ol.Map');
goog.require('ol.RendererHint');
goog.require('ol.View2D');
goog.require('ol.layer.TileLayer');
goog.require('ol.projection');
goog.require('ol.source.TiledWMS');
if (goog.DEBUG) {
goog.debug.Console.autoInstall();
goog.debug.Logger.getLogger('ol').setLevel(goog.debug.Logger.Level.INFO);
}
var epsg4326 = ol.projection.getFromCode('EPSG:4326');
// We give the single image source a set of resolutions. This prevents the
// source from requesting images of arbitrary resolutions.
var projectionExtent = epsg4326.getExtent();
var maxResolution = Math.max(
projectionExtent.maxX - projectionExtent.minX,
projectionExtent.maxY - projectionExtent.minY) / 256;
var resolutions = new Array(10);
for (var i = 0; i < 10; ++i) {
resolutions[i] = maxResolution / Math.pow(2.0, i);
}
var layers = new ol.Collection([
new ol.layer.TileLayer({
source: new ol.source.TiledWMS({
url: 'http://vmap0.tiles.osgeo.org/wms/vmap0',
crossOrigin: null,
params: {
'LAYERS': 'basic',
'FORMAT': 'image/jpeg'
},
projection: epsg4326
})
})
]);
var map = new ol.Map({
layers: layers,
// The OSgeo server does not set cross origin headers, so we cannot use WebGL
renderers: [ol.RendererHint.CANVAS, ol.RendererHint.DOM],
target: 'map',
view: new ol.View2D({
projection: epsg4326,
center: new ol.Coordinate(0, 0),
zoom: 2
})
});