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openlayers

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Build tools and sources for developing OpenLayers based mapping applications

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goog.provide('ol.TileCache'); goog.require('ol'); goog.require('ol.structs.LRUCache'); /** * @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); /** * @private * @type {number} */ this.highWaterMark_ = opt_highWaterMark !== undefined ? opt_highWaterMark : 2048; }; ol.inherits(ol.TileCache, ol.structs.LRUCache); /** * @return {boolean} Can expire cache. */ ol.TileCache.prototype.canExpireCache = function() { return this.getCount() > this.highWaterMark_; }; /** * @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(); } } };