Files
openlayers/src/ol/dom/tilelayerrenderer.js
2012-08-03 11:13:01 +02:00

154 lines
4.2 KiB
JavaScript

// FIXME ol.dom.TileLayerRenderer should cope with "not ready" layers
// FIXME ol.dom.TileLayerRenderer should re-render when layer loads
goog.provide('ol.dom.TileLayerRenderer');
goog.require('goog.dom');
goog.require('ol.Coordinate');
goog.require('ol.Extent');
goog.require('ol.dom.LayerRenderer');
/**
* @constructor
* @extends {ol.dom.LayerRenderer}
* @param {ol.dom.Map} map Map.
* @param {ol.TileLayer} tileLayer Tile layer.
* @param {!Element} target Target.
*/
ol.dom.TileLayerRenderer = function(map, tileLayer, target) {
goog.base(this, map, tileLayer, target);
/**
* @type {Object}
* @private
*/
this.renderedTiles_ = {};
/**
* @type {number|undefined}
* @private
*/
this.renderedMapResolution_ = undefined;
};
goog.inherits(ol.dom.TileLayerRenderer, ol.dom.LayerRenderer);
/**
* @override
* @return {ol.TileLayer} Layer.
*/
ol.dom.TileLayerRenderer.prototype.getLayer = function() {
return /** @type {ol.TileLayer} */ goog.base(this, 'getLayer');
};
/**
* @inheritDoc
*/
ol.dom.TileLayerRenderer.prototype.render = function() {
var map = this.getMap();
if (!map.isDef()) {
return;
}
var mapExtent = /** @type {!ol.Extent} */ map.getExtent();
var mapResolution = /** @type {number} */ map.getResolution();
var tileLayer = this.getLayer();
var tileStore = tileLayer.getStore();
var tileGrid = tileStore.getTileGrid();
if (mapResolution != this.renderedMapResolution_) {
this.renderedTiles_ = {};
goog.dom.removeChildren(this.target);
}
// z represents the "best" resolution
var z = tileGrid.getZForResolution(mapResolution);
var tileBounds =
tileGrid.getTileBoundsForExtentAndResolution(mapExtent, mapResolution);
var tileOffset = this.getTileOffset_(z, mapResolution);
var fragment = document.createDocumentFragment();
var key, tile, pixelBounds, img, newTiles = false;
tileBounds.forEachTileCoord(z, function(tileCoord) {
key = tileCoord.toString();
tile = this.renderedTiles_[key];
if (!goog.isDef(tile)) {
tile = tileStore.getTile(tileCoord);
if (goog.isNull(tile)) {
} else {
if (!tile.isLoaded()) {
tile.load();
}
this.renderedTiles_[key] = tile;
pixelBounds = tileGrid.getPixelBoundsForTileCoordAndResolution(
tileCoord, mapResolution);
img = tile.getImage(this);
img.style.position = 'absolute';
img.style.left = (pixelBounds.minX - tileOffset.x) + 'px';
img.style.top = (-pixelBounds.maxY - tileOffset.y) + 'px';
img.style.width = pixelBounds.getWidth() + 'px';
img.style.height = pixelBounds.getHeight() + 'px';
goog.dom.appendChild(fragment, img);
newTiles = true;
}
}
}, this);
if (newTiles) {
goog.dom.appendChild(this.target, fragment);
}
this.removeInvisibleTiles_(tileBounds, z);
this.renderedMapResolution_ = mapResolution;
};
/**
* Get the pixel offset between the tile origin and the container origin.
* @private
* @param {number} z Z.
* @param {number} resolution Resolution.
* @return {ol.Coordinate} Offset.
*/
ol.dom.TileLayerRenderer.prototype.getTileOffset_ = function(z, resolution) {
var tileLayer = this.getLayer();
var tileStore = tileLayer.getStore();
var tileGrid = tileStore.getTileGrid();
var tileOrigin = tileGrid.getOrigin(z);
var offset = new ol.Coordinate(
Math.round((this.origin.x - tileOrigin.x) / resolution),
Math.round((tileOrigin.y - this.origin.y) / resolution));
return offset;
};
/**
* Get rid of tiles outside the rendered extent.
* @private
* @param {ol.TileBounds} tileBounds Tile bounds.
* @param {number} z Z.
*/
ol.dom.TileLayerRenderer.prototype.removeInvisibleTiles_ = function(
tileBounds, z) {
var key, tileCoord, prune, tile;
for (key in this.renderedTiles_) {
tileCoord = ol.TileCoord.createFromString(key);
prune = z !== tileCoord.z ||
tileCoord.x < tileBounds.minX ||
tileCoord.x > tileBounds.maxX ||
tileCoord.y < tileBounds.minY ||
tileCoord.y > tileBounds.maxY;
if (prune) {
tile = this.renderedTiles_[key];
delete this.renderedTiles_[key];
goog.dom.removeNode(tile.getImage(this));
}
}
};