94 lines
2.1 KiB
JavaScript
94 lines
2.1 KiB
JavaScript
goog.provide('ol.TilePriorityFunction');
|
|
goog.provide('ol.TileQueue');
|
|
|
|
goog.require('goog.events');
|
|
goog.require('goog.events.EventType');
|
|
goog.require('ol.Coordinate');
|
|
goog.require('ol.Tile');
|
|
goog.require('ol.structs.PriorityQueue');
|
|
|
|
|
|
/**
|
|
* @typedef {function(ol.Tile, string, ol.Coordinate, number): number}
|
|
*/
|
|
ol.TilePriorityFunction;
|
|
|
|
|
|
|
|
/**
|
|
* @constructor
|
|
* @extends {ol.structs.PriorityQueue}
|
|
* @param {ol.TilePriorityFunction} tilePriorityFunction
|
|
* Tile priority function.
|
|
* @param {function(): ?} tileChangeCallback
|
|
* Function called on each tile change event.
|
|
*/
|
|
ol.TileQueue = function(tilePriorityFunction, tileChangeCallback) {
|
|
|
|
goog.base(
|
|
this,
|
|
/**
|
|
* @param {Array} element Element.
|
|
* @return {number} Priority.
|
|
*/
|
|
function(element) {
|
|
return tilePriorityFunction.apply(null, element);
|
|
},
|
|
/**
|
|
* @param {Array} element Element.
|
|
* @return {string} Key.
|
|
*/
|
|
function(element) {
|
|
return /** @type {ol.Tile} */ (element[0]).getKey();
|
|
});
|
|
|
|
/**
|
|
* @private
|
|
* @type {function(): ?}
|
|
*/
|
|
this.tileChangeCallback_ = tileChangeCallback;
|
|
|
|
/**
|
|
* @private
|
|
* @type {number}
|
|
*/
|
|
this.tilesLoading_ = 0;
|
|
|
|
};
|
|
goog.inherits(ol.TileQueue, ol.structs.PriorityQueue);
|
|
|
|
|
|
/**
|
|
* @return {number} Number of tiles loading.
|
|
*/
|
|
ol.TileQueue.prototype.getTilesLoading = function() {
|
|
return this.tilesLoading_;
|
|
};
|
|
|
|
|
|
/**
|
|
* @protected
|
|
*/
|
|
ol.TileQueue.prototype.handleTileChange = function() {
|
|
--this.tilesLoading_;
|
|
this.tileChangeCallback_();
|
|
};
|
|
|
|
|
|
/**
|
|
* @param {number} maxTotalLoading Maximum number tiles to load simultaneously.
|
|
* @param {number} maxNewLoads Maximum number of new tiles to load.
|
|
*/
|
|
ol.TileQueue.prototype.loadMoreTiles = function(maxTotalLoading, maxNewLoads) {
|
|
var newLoads = Math.min(
|
|
maxTotalLoading - this.getTilesLoading(), maxNewLoads, this.getCount());
|
|
var i, tile;
|
|
for (i = 0; i < newLoads; ++i) {
|
|
tile = /** @type {ol.Tile} */ (this.dequeue()[0]);
|
|
goog.events.listenOnce(tile, goog.events.EventType.CHANGE,
|
|
this.handleTileChange, false, this);
|
|
tile.load();
|
|
}
|
|
this.tilesLoading_ += newLoads;
|
|
};
|