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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.reproj.Tile'); goog.require('ol'); goog.require('ol.Tile'); goog.require('ol.events'); goog.require('ol.events.EventType'); goog.require('ol.extent'); goog.require('ol.math'); goog.require('ol.reproj'); goog.require('ol.reproj.Triangulation'); /** * @classdesc * Class encapsulating single reprojected tile. * See {@link ol.source.TileImage}. * * @constructor * @extends {ol.Tile} * @param {ol.proj.Projection} sourceProj Source projection. * @param {ol.tilegrid.TileGrid} sourceTileGrid Source tile grid. * @param {ol.proj.Projection} targetProj Target projection. * @param {ol.tilegrid.TileGrid} targetTileGrid Target tile grid. * @param {ol.TileCoord} tileCoord Coordinate of the tile. * @param {ol.TileCoord} wrappedTileCoord Coordinate of the tile wrapped in X. * @param {number} pixelRatio Pixel ratio. * @param {number} gutter Gutter of the source tiles. * @param {ol.ReprojTileFunctionType} getTileFunction * Function returning source tiles (z, x, y, pixelRatio). * @param {number=} opt_errorThreshold Acceptable reprojection error (in px). * @param {boolean=} opt_renderEdges Render reprojection edges. */ ol.reproj.Tile = function(sourceProj, sourceTileGrid, targetProj, targetTileGrid, tileCoord, wrappedTileCoord, pixelRatio, gutter, getTileFunction, opt_errorThreshold, opt_renderEdges) { ol.Tile.call(this, tileCoord, ol.Tile.State.IDLE); /** * @private * @type {boolean} */ this.renderEdges_ = opt_renderEdges !== undefined ? opt_renderEdges : false; /** * @private * @type {number} */ this.pixelRatio_ = pixelRatio; /** * @private * @type {number} */ this.gutter_ = gutter; /** * @private * @type {HTMLCanvasElement} */ this.canvas_ = null; /** * @private * @type {ol.tilegrid.TileGrid} */ this.sourceTileGrid_ = sourceTileGrid; /** * @private * @type {ol.tilegrid.TileGrid} */ this.targetTileGrid_ = targetTileGrid; /** * @private * @type {ol.TileCoord} */ this.wrappedTileCoord_ = wrappedTileCoord ? wrappedTileCoord : tileCoord; /** * @private * @type {!Array.<ol.Tile>} */ this.sourceTiles_ = []; /** * @private * @type {Array.<ol.EventsKey>} */ this.sourcesListenerKeys_ = null; /** * @private * @type {number} */ this.sourceZ_ = 0; var targetExtent = targetTileGrid.getTileCoordExtent(this.wrappedTileCoord_); var maxTargetExtent = this.targetTileGrid_.getExtent(); var maxSourceExtent = this.sourceTileGrid_.getExtent(); var limitedTargetExtent = maxTargetExtent ? ol.extent.getIntersection(targetExtent, maxTargetExtent) : targetExtent; if (ol.extent.getArea(limitedTargetExtent) === 0) { // Tile is completely outside range -> EMPTY // TODO: is it actually correct that the source even creates the tile ? this.state = ol.Tile.State.EMPTY; return; } var sourceProjExtent = sourceProj.getExtent(); if (sourceProjExtent) { if (!maxSourceExtent) { maxSourceExtent = sourceProjExtent; } else { maxSourceExtent = ol.extent.getIntersection( maxSourceExtent, sourceProjExtent); } } var targetResolution = targetTileGrid.getResolution( this.wrappedTileCoord_[0]); var targetCenter = ol.extent.getCenter(limitedTargetExtent); var sourceResolution = ol.reproj.calculateSourceResolution( sourceProj, targetProj, targetCenter, targetResolution); if (!isFinite(sourceResolution) || sourceResolution <= 0) { // invalid sourceResolution -> EMPTY // probably edges of the projections when no extent is defined this.state = ol.Tile.State.EMPTY; return; } var errorThresholdInPixels = opt_errorThreshold !== undefined ? opt_errorThreshold : ol.DEFAULT_RASTER_REPROJECTION_ERROR_THRESHOLD; /** * @private * @type {!ol.reproj.Triangulation} */ this.triangulation_ = new ol.reproj.Triangulation( sourceProj, targetProj, limitedTargetExtent, maxSourceExtent, sourceResolution * errorThresholdInPixels); if (this.triangulation_.getTriangles().length === 0) { // no valid triangles -> EMPTY this.state = ol.Tile.State.EMPTY; return; } this.sourceZ_ = sourceTileGrid.getZForResolution(sourceResolution); var sourceExtent = this.triangulation_.calculateSourceExtent(); if (maxSourceExtent) { if (sourceProj.canWrapX()) { sourceExtent[1] = ol.math.clamp( sourceExtent[1], maxSourceExtent[1], maxSourceExtent[3]); sourceExtent[3] = ol.math.clamp( sourceExtent[3], maxSourceExtent[1], maxSourceExtent[3]); } else { sourceExtent = ol.extent.getIntersection(sourceExtent, maxSourceExtent); } } if (!ol.extent.getArea(sourceExtent)) { this.state = ol.Tile.State.EMPTY; } else { var sourceRange = sourceTileGrid.getTileRangeForExtentAndZ( sourceExtent, this.sourceZ_); var tilesRequired = sourceRange.getWidth() * sourceRange.getHeight(); if (ol.DEBUG && !(tilesRequired < ol.RASTER_REPROJECTION_MAX_SOURCE_TILES)) { console.assert(false, 'reasonable number of tiles is required'); this.state = ol.Tile.State.ERROR; return; } for (var srcX = sourceRange.minX; srcX <= sourceRange.maxX; srcX++) { for (var srcY = sourceRange.minY; srcY <= sourceRange.maxY; srcY++) { var tile = getTileFunction(this.sourceZ_, srcX, srcY, pixelRatio); if (tile) { this.sourceTiles_.push(tile); } } } if (this.sourceTiles_.length === 0) { this.state = ol.Tile.State.EMPTY; } } }; ol.inherits(ol.reproj.Tile, ol.Tile); /** * @inheritDoc */ ol.reproj.Tile.prototype.disposeInternal = function() { if (this.state == ol.Tile.State.LOADING) { this.unlistenSources_(); } ol.Tile.prototype.disposeInternal.call(this); }; /** * @inheritDoc */ ol.reproj.Tile.prototype.getImage = function() { return this.canvas_; }; /** * @private */ ol.reproj.Tile.prototype.reproject_ = function() { var sources = []; this.sourceTiles_.forEach(function(tile, i, arr) { if (tile && tile.getState() == ol.Tile.State.LOADED) { sources.push({ extent: this.sourceTileGrid_.getTileCoordExtent(tile.tileCoord), image: tile.getImage() }); } }, this); this.sourceTiles_.length = 0; if (sources.length === 0) { this.state = ol.Tile.State.ERROR; } else { var z = this.wrappedTileCoord_[0]; var size = this.targetTileGrid_.getTileSize(z); var width = typeof size === 'number' ? size : size[0]; var height = typeof size === 'number' ? size : size[1]; var targetResolution = this.targetTileGrid_.getResolution(z); var sourceResolution = this.sourceTileGrid_.getResolution(this.sourceZ_); var targetExtent = this.targetTileGrid_.getTileCoordExtent( this.wrappedTileCoord_); this.canvas_ = ol.reproj.render(width, height, this.pixelRatio_, sourceResolution, this.sourceTileGrid_.getExtent(), targetResolution, targetExtent, this.triangulation_, sources, this.gutter_, this.renderEdges_); this.state = ol.Tile.State.LOADED; } this.changed(); }; /** * @inheritDoc */ ol.reproj.Tile.prototype.load = function() { if (this.state == ol.Tile.State.IDLE) { this.state = ol.Tile.State.LOADING; this.changed(); var leftToLoad = 0; ol.DEBUG && console.assert(!this.sourcesListenerKeys_, 'this.sourcesListenerKeys_ should be null'); this.sourcesListenerKeys_ = []; this.sourceTiles_.forEach(function(tile, i, arr) { var state = tile.getState(); if (state == ol.Tile.State.IDLE || state == ol.Tile.State.LOADING) { leftToLoad++; var sourceListenKey; sourceListenKey = ol.events.listen(tile, ol.events.EventType.CHANGE, function(e) { var state = tile.getState(); if (state == ol.Tile.State.LOADED || state == ol.Tile.State.ERROR || state == ol.Tile.State.EMPTY) { ol.events.unlistenByKey(sourceListenKey); leftToLoad--; ol.DEBUG && console.assert(leftToLoad >= 0, 'leftToLoad should not be negative'); if (leftToLoad === 0) { this.unlistenSources_(); this.reproject_(); } } }, this); this.sourcesListenerKeys_.push(sourceListenKey); } }, this); this.sourceTiles_.forEach(function(tile, i, arr) { var state = tile.getState(); if (state == ol.Tile.State.IDLE) { tile.load(); } }); if (leftToLoad === 0) { setTimeout(this.reproject_.bind(this), 0); } } }; /** * @private */ ol.reproj.Tile.prototype.unlistenSources_ = function() { this.sourcesListenerKeys_.forEach(ol.events.unlistenByKey); this.sourcesListenerKeys_ = null; };