Files
openlayers/src/ol/tilecache.js

56 lines
1.2 KiB
JavaScript

goog.provide('ol.TileCache');
goog.require('ol');
goog.require('ol.structs.LRUCache');
goog.require('ol.tilecoord');
/**
* @constructor
* @extends {ol.structs.LRUCache.<ol.Tile>}
* @param {number=} opt_highWaterMark High water mark.
* @struct
*/
ol.TileCache = function(opt_highWaterMark) {
ol.structs.LRUCache.call(this, opt_highWaterMark);
};
ol.inherits(ol.TileCache, ol.structs.LRUCache);
/**
* @param {Object.<string, ol.TileRange>} usedTiles Used tiles.
*/
ol.TileCache.prototype.expireCache = function(usedTiles) {
var tile, zKey;
while (this.canExpireCache()) {
tile = this.peekLast();
zKey = tile.tileCoord[0].toString();
if (zKey in usedTiles && usedTiles[zKey].contains(tile.tileCoord)) {
break;
} else {
this.pop().dispose();
}
}
};
/**
* Prune all tiles from the cache that don't have the same z as the newest tile.
*/
ol.TileCache.prototype.pruneExceptNewestZ = function() {
if (this.getCount() === 0) {
return;
}
var key = this.peekFirstKey();
var tileCoord = ol.tilecoord.fromKey(key);
var z = tileCoord[0];
this.forEach(function(tile) {
if (tile.tileCoord[0] !== z) {
this.remove(ol.tilecoord.getKey(tile.tileCoord));
tile.dispose();
}
}, this);
};