Files
openlayers/src/ol/source/singleimagewmssource.js
2013-03-14 14:29:51 +01:00

71 lines
1.7 KiB
JavaScript

goog.provide('ol.source.SingleImageWMS');
goog.require('ol.Extent');
goog.require('ol.Image');
goog.require('ol.ImageUrlFunction');
goog.require('ol.Size');
goog.require('ol.source.ImageSource');
/**
* @constructor
* @extends {ol.source.ImageSource}
* @param {ol.source.SingleImageWMSOptions} options Options.
*/
ol.source.SingleImageWMS = function(options) {
var imageUrlFunction = goog.isDef(options.url) ?
ol.ImageUrlFunction.createWMSParams(options.url, options.params) :
ol.ImageUrlFunction.nullImageUrlFunction;
goog.base(this, {
attributions: options.attributions,
crossOrigin: options.crossOrigin,
extent: options.extent,
projection: options.projection,
resolutions: options.resolutions,
imageUrlFunction: imageUrlFunction
});
/**
* @private
* @type {ol.Image}
*/
this.image_ = null;
/**
* @private
* @type {number}
*/
this.ratio_ = goog.isDef(options.ratio) ?
options.ratio : 1.5;
};
goog.inherits(ol.source.SingleImageWMS, ol.source.ImageSource);
/**
* @inheritDoc
*/
ol.source.SingleImageWMS.prototype.getImage =
function(extent, resolution, projection) {
resolution = this.findNearestResolution(resolution);
var image = this.image_;
if (!goog.isNull(image) &&
image.getResolution() == resolution &&
image.getExtent().containsExtent(extent)) {
return image;
}
extent = new ol.Extent(extent.minX, extent.minY,
extent.maxX, extent.maxY);
extent.scaleFromCenter(this.ratio_);
var width = extent.getWidth() / resolution;
var height = extent.getHeight() / resolution;
var size = new ol.Size(width, height);
this.image_ = this.createImage(extent, resolution, size, projection);
return this.image_;
};