openlayers
Version:
Build tools and sources for developing OpenLayers based mapping applications
114 lines (94 loc) • 2.85 kB
JavaScript
goog.provide('ol.source.TileDebug');
goog.require('ol');
goog.require('ol.Tile');
goog.require('ol.dom');
goog.require('ol.size');
goog.require('ol.source.Tile');
/**
* @classdesc
* A pseudo tile source, which does not fetch tiles from a server, but renders
* a grid outline for the tile grid/projection along with the coordinates for
* each tile. See examples/canvas-tiles for an example.
*
* Uses Canvas context2d, so requires Canvas support.
*
* @constructor
* @extends {ol.source.Tile}
* @param {olx.source.TileDebugOptions} options Debug tile options.
* @api
*/
ol.source.TileDebug = function(options) {
ol.source.Tile.call(this, {
opaque: false,
projection: options.projection,
tileGrid: options.tileGrid,
wrapX: options.wrapX !== undefined ? options.wrapX : true
});
};
ol.inherits(ol.source.TileDebug, ol.source.Tile);
/**
* @inheritDoc
*/
ol.source.TileDebug.prototype.getTile = function(z, x, y) {
var tileCoordKey = this.getKeyZXY(z, x, y);
if (this.tileCache.containsKey(tileCoordKey)) {
return /** @type {!ol.source.TileDebug.Tile_} */ (this.tileCache.get(tileCoordKey));
} else {
var tileSize = ol.size.toSize(this.tileGrid.getTileSize(z));
var tileCoord = [z, x, y];
var textTileCoord = this.getTileCoordForTileUrlFunction(tileCoord);
var text = !textTileCoord ? '' :
this.getTileCoordForTileUrlFunction(textTileCoord).toString();
var tile = new ol.source.TileDebug.Tile_(tileCoord, tileSize, text);
this.tileCache.set(tileCoordKey, tile);
return tile;
}
};
/**
* @constructor
* @extends {ol.Tile}
* @param {ol.TileCoord} tileCoord Tile coordinate.
* @param {ol.Size} tileSize Tile size.
* @param {string} text Text.
* @private
*/
ol.source.TileDebug.Tile_ = function(tileCoord, tileSize, text) {
ol.Tile.call(this, tileCoord, ol.Tile.State.LOADED);
/**
* @private
* @type {ol.Size}
*/
this.tileSize_ = tileSize;
/**
* @private
* @type {string}
*/
this.text_ = text;
/**
* @private
* @type {HTMLCanvasElement}
*/
this.canvas_ = null;
};
ol.inherits(ol.source.TileDebug.Tile_, ol.Tile);
/**
* Get the image element for this tile.
* @return {HTMLCanvasElement} Image.
*/
ol.source.TileDebug.Tile_.prototype.getImage = function() {
if (this.canvas_) {
return this.canvas_;
} else {
var tileSize = this.tileSize_;
var context = ol.dom.createCanvasContext2D(tileSize[0], tileSize[1]);
context.strokeStyle = 'black';
context.strokeRect(0.5, 0.5, tileSize[0] + 0.5, tileSize[1] + 0.5);
context.fillStyle = 'black';
context.textAlign = 'center';
context.textBaseline = 'middle';
context.font = '24px sans-serif';
context.fillText(this.text_, tileSize[0] / 2, tileSize[1] / 2);
this.canvas_ = context.canvas;
return context.canvas;
}
};