// The original code is here: https://github.com/manuelnas/CesiumHeatmap/blob/master/HeatmapImageryProvider.js
// the author does not provider any license description
// the license of HeatMap.js is here : https://github.com/pa7/heatmap.js/blob/master/LICENSE
// I did nothing but just make this file easier for Cesiumer to load
(function (window) {
var HeatmapImageryProvider = function (options) {
options = Cesium.defaultValue(options, {});
var arrPoint = options.data;
if (!Cesium.defined(arrPoint) || arrPoint.length == 0) {
throw new Cesium.DeveloperError('data is required.');
}
this._options = Cesium.defaultValue(options.heatmapoptions, {});
this._options.xField = Cesium.defaultValue(this._options.xField, 'x');
this._options.yField = Cesium.defaultValue(this._options.yField, 'y');
this._options.valueField = Cesium.defaultValue(this._options.valueField, 'value');
//计算数据的最大最小值和边界 start
var _x = arrPoint[0][this._options.xField];
var _y = arrPoint[0][this._options.yField];
var _value = arrPoint[0][this._options.valueField];
var bounds = { "east": _x, "west": _x, "north": _y, "south": _y };
var min = _value;
var max = _value;
for (var i = 0; i < arrPoint.length; i++) {
_x = arrPoint[i][this._options.xField];
_y = arrPoint[i][this._options.yField];
_value = arrPoint[i][this._options.valueField];
if (min > _value) min = _value;
if (max < _value) max = _value;
if (_x > bounds.east) bounds.east = _x;
if (_x < bounds.west) bounds.west = _x;
if (_y > bounds.north) bounds.north = _y;
if (_y < bounds.south) bounds.south = _y;
}
//计算数据的最大最小值和边界 end
if (Cesium.defined(options.min)) {
min = options.min;
}
if (Cesium.defined(options.max)) {
max = options.max;
}
this._min = min;
this._max= max;
this._data =arrPoint;
var chInstance = options.chInstance || h337;
this._wmp = new Cesium.WebMercatorProjection();
this._mbounds = this.wgs84ToMercatorBB(bounds);
this._options.gradient = Cesium.defaultValue(this._options.gradient, { 0.25: "rgb(0,0,255)", 0.55: "rgb(0,255,0)", 0.85: "yellow", 1.0: "rgb(255,0,0)" });
this._setWidthAndHeight(this._mbounds);
this._options.radius = Cesium.defaultValue(this._options.radius, Math.round(Cesium.defaultValue(this._options.radius, ((this.width > this.height) ? this.width / 60 : this.height / 60))));
this._spacing = this._options.radius * 1.5;
this._xoffset = this._mbounds.west;
this._yoffset = this._mbounds.south;
this.width = Math.round(this.width + this._spacing * 2);
this.height = Math.round(this.height + this._spacing * 2);
this._mbounds.west -= this._spacing * this._factor;
this._mbounds.east += this._spacing * this._factor;
this._mbounds.south -= this._spacing * this._factor;
this._mbounds.north += this._spacing * this._factor;
this.bounds = this.mercatorToWgs84BB(this._mbounds);
this._container = this._getContainer(this.width, this.height);
this._options.container = this._container;
this._heatmap = chInstance.create(this._options); //热力图对象
this._image = this._canvas = this._container.children[0];
this._tilingScheme = new Cesium.WebMercatorTilingScheme({
rectangleSouthwestInMeters: new Cesium.Cartesian2(this._mbounds.west, this._mbounds.south),
rectangleNortheastInMeters: new Cesium.Cartesian2(this._mbounds.east, this._mbounds.north)
});
this._texture = undefined;
this._tileWidth = this.width;
this._tileHeight = this.height;
this._ready = false;
this.readyPromise = Cesium.when.defer();
this._ready = this.setWGS84Data( this._min, this._max, this._data);
this.readyPromise.resolve(true);
};
Cesium.defineProperties(HeatmapImageryProvider.prototype, {
/**
* Gets the URL of the single, top-level imagery tile.
* @memberof HeatmapImageryProvider.prototype
* @type {String}
* @readonly
*/
url: {
get: function () {
return this._url;
}
},
/**
* Gets the width of each tile, in pixels. This function should
* not be called before {@link HeatmapImageryProvider#ready} returns true.
* @memberof HeatmapImageryProvider.prototype
* @type {Number}
* @readonly
*/
tileWidth: {
get: function () {
if (!this._ready) {
throw new Cesium.DeveloperError('tileWidth must not be called before the imagery provider is ready.');
}
return this._tileWidth;
}
},
/**
* Gets the height of each tile, in pixels. This function should
* not be called before {@link HeatmapImageryProvider#ready} returns true.
* @memberof HeatmapImageryProvider.prototype
* @type {Number}
* @readonly
*/
tileHeight: {
get: function () {
if (!this._ready) {
throw new Cesium.DeveloperError('tileHeight must not be called before the imagery provider is ready.');
}
return this._tileHeight;
}
},
/**
* Gets the maximum level-of-detail that can be requested. This function should
* not be called before {@link HeatmapImageryProvider#ready} returns true.
* @memberof HeatmapImageryProvider.prototype
* @type {Number}
* @readonly
*/
maximumLevel: {
get: function () {
if (!this._ready) {
throw new Cesium.DeveloperError('maximumLevel must not be called before the imagery provider is ready.');
}
return 0;
}
},
/**
* Gets the minimum level-of-detail that can be requested. This function should
* not be called before {@link HeatmapImageryProvider#ready} returns true.
* @memberof HeatmapImageryProvider.prototype
* @type {Number}
* @readonly
*/
minimumLevel: {
get: function () {
if (!this._ready) {
throw new Cesium.DeveloperError('minimumLevel must not be called before the imagery provider is ready.');
}
return 0;
}
},
/**
* Gets the tiling scheme used by this provider. This function should
* not be called before {@link HeatmapImageryProvider#ready} returns true.
* @memberof HeatmapImageryProvider.prototype
* @type {TilingScheme}
* @readonly
*/
tilingScheme: {
get: function () {
if (!this._ready) {
throw new Cesium.DeveloperError('tilingScheme must not be called before the imagery provider is ready.');
}
return this._tilingScheme;
}
},
/**
* Gets the rectangle, in radians, of the imagery provided by this instance. This function should
* not be called before {@link HeatmapImageryProvider#ready} returns true.
* @memberof HeatmapImageryProvider.prototype
* @type {Rectangle}
* @readonly
*/
rectangle: {
get: function () {
return this._tilingScheme.rectangle;//TODO: change to custom rectangle?
}
},
/**
* Gets the tile discard policy. If not undefined, the discard policy is responsible
* for filtering out "missing" tiles via its shouldDiscardImage function. If this function
* returns undefined, no tiles are filtered. This function should
* not be called before {@link HeatmapImageryProvider#ready} returns true.
* @memberof HeatmapImageryProvider.prototype
* @type {TileDiscardPolicy}
* @readonly
*/
tileDiscardPolicy: {
get: function () {
if (!this._ready) {
throw new Cesium.DeveloperError('tileDiscardPolicy must not be called before the imagery provider is ready.');
}
return undefined;
}
},
/**
* Gets an event that is raised when the imagery provider encounters an asynchronous error. By subscribing
* to the event, you will be notified of the error and can potentially recover from it. Event listeners
* are passed an instance of {@link TileProviderError}.
* @memberof HeatmapImageryProvider.prototype
* @type {Event}
* @readonly
*/
errorEvent: {
get: function () {
return this._errorEvent;
}
},
/**
* Gets a value indicating whether or not the provider is ready for use.
* @memberof HeatmapImageryProvider.prototype
* @type {Boolean}
* @readonly
*/
ready: {
get: function () {
return this._ready;
}
},
/**
* Gets the credit to display when this imagery provider is active. Typically this is used to credit
* the source of the imagery. This function should not be called before {@link HeatmapImageryProvider#ready} returns true.
* @memberof HeatmapImageryProvider.prototype
* @type {Credit}
* @readonly
*/
credit: {
get: function () {
return this._credit;
}
},
/**
* Gets a value indicating whether or not the images provided by this imagery provider
* include an alpha channel. If this property is false, an alpha channel, if present, will
* be ignored. If this property is true, any images without an alpha channel will be treated
* as if their alpha is 1.0 everywhere. When this property is false, memory usage
* and texture upload time are reduced.
* @memberof HeatmapImageryProvider.prototype
* @type {Boolean}
* @readonly
*/
hasAlphaChannel: {
get: function () {
return true;
}
}
});
HeatmapImageryProvider.prototype._setWidthAndHeight = function (mbb) {
var maxCanvasSize = 2000;
var minCanvasSize = 700;
this.width = ((mbb.east > 0 && mbb.west < 0) ? mbb.east + Math.abs(mbb.west) : Math.abs(mbb.east - mbb.west));
this.height = ((mbb.north > 0 && mbb.south < 0) ? mbb.north + Math.abs(mbb.south) : Math.abs(mbb.north - mbb.south));
this._factor = 1;
if (this.width > this.height && this.width > maxCanvasSize) {
this._factor = this.width / maxCanvasSize;
if (this.height / this._factor < minCanvasSize) {
this._factor = this.height / minCanvasSize;
}
} else if (this.height > this.width && this.height > maxCanvasSize) {
this._factor = this.height / maxCanvasSize;
if (this.width / this._factor < minCanvasSize) {
this._factor = this.width / minCanvasSize;
}
} else if (this.width < this.height && this.width < minCanvasSize) {
this._factor = this.width / minCanvasSize;
if (this.height / this._factor > maxCanvasSize) {
this._factor = this.height / maxCanvasSize;
}
} else if (this.height < this.width && this.height < minCanvasSize) {
this._factor = this.height / minCanvasSize;
if (this.width / this._factor > maxCanvasSize) {
this._factor = this.width / maxCanvasSize;
}
}
this.width = this.width / this._factor;
this.height = this.height / this._factor;
};
HeatmapImageryProvider.prototype._getContainer = function (width, height, id) {
var c = document.createElement("div");
if (id) { c.setAttribute("id", id); }
c.setAttribute("style", "width: " + width + "px; height: " + height + "px; margin: 0px; display: none;");
document.body.appendChild(c);
return c;
};
/**
* Convert a WGS84 location into a Mercator location.
*
* @param {Object} point The WGS84 location.
* @param {Number} [point.x] The longitude of the location.
* @param {Number} [point.y] The latitude of the location.
* @returns {Cartesian3} The Mercator location.
*/
HeatmapImageryProvider.prototype.wgs84ToMercator = function (point) {
return this._wmp.project(Cesium.Cartographic.fromDegrees(point[this._options.xField], point[this._options.yField]));
};
/**
* Convert a WGS84 bounding box into a Mercator bounding box.
*
* @param {Object} bounds The WGS84 bounding box.
* @param {Number} [bounds.north] The northernmost position.
* @param {Number} [bounds.south] The southrnmost position.
* @param {Number} [bounds.east] The easternmost position.
* @param {Number} [bounds.west] The westernmost position.
* @returns {Object} The Mercator bounding box containing north, south, east and west properties.
*/
HeatmapImageryProvider.prototype.wgs84ToMercatorBB = function (bounds) {
var ne = this._wmp.project(Cesium.Cartographic.fromDegrees(bounds.east, bounds.north));
var sw = this._wmp.project(Cesium.Cartographic.fromDegrees(bounds.west, bounds.south));
return {
north: ne.y,
south: sw.y,
east: ne.x,
west: sw.x
};
};
/**
* Convert a mercator location into a WGS84 location.
*
* @param {Object} point The Mercator lcation.
* @param {Number} [point.x] The x of the location.
* @param {Number} [point.y] The y of the location.
* @returns {Object} The WGS84 location.
*/
HeatmapImageryProvider.prototype.mercatorToWgs84 = function (p) {
var wp = this._wmp.unproject(new Cesium.Cartesian3(p.x, p.y));
return {
x: wp.longitude,
y: wp.latitude
};
};
/**
* Convert a Mercator bounding box into a WGS84 bounding box.
*
* @param {Object} bounds The Mercator bounding box.
* @param {Number} [bounds.north] The northernmost position.
* @param {Number} [bounds.south] The southrnmost position.
* @param {Number} [bounds.east] The easternmost position.
* @param {Number} [bounds.west] The westernmost position.
* @returns {Object} The WGS84 bounding box containing north, south, east and west properties.
*/
HeatmapImageryProvider.prototype.mercatorToWgs84BB = function (bounds) {
var sw = this._wmp.unproject(new Cesium.Cartesian3(bounds.west, bounds.south));
var ne = this._wmp.unproject(new Cesium.Cartesian3(bounds.east, bounds.north));
return {
north: this.rad2deg(ne.latitude),
east: this.rad2deg(ne.longitude),
south: this.rad2deg(sw.latitude),
west: this.rad2deg(sw.longitude)
};
};
/**
* Convert degrees into radians.
*
* @param {Number} degrees The degrees to be converted to radians.
* @returns {Number} The converted radians.
*/
HeatmapImageryProvider.prototype.deg2rad = function (degrees) {
return (degrees * (Math.PI / 180.0));
};
/**
* Convert radians into degrees.
*
* @param {Number} radians The radians to be converted to degrees.
* @returns {Number} The converted degrees.
*/
HeatmapImageryProvider.prototype.rad2deg = function (radians) {
return (radians / (Math.PI / 180.0));
};
/**
* Convert a WGS84 location to the corresponding heatmap location.
*
* @param {Object} point The WGS84 location.
* @param {Number} [point.x] The longitude of the location.
* @param {Number} [point.y] The latitude of the location.
* @returns {Object} The corresponding heatmap location.
*/
HeatmapImageryProvider.prototype.wgs84PointToHeatmapPoint = function (point) {
return this.mercatorPointToHeatmapPoint(this.wgs84ToMercator(point));
};
/**
* Convert a mercator location to the corresponding heatmap location.
*
* @param {Object} point The Mercator lcation.
* @param {Number} [point.x] The x of the location.
* @param {Number} [point.y] The y of the location.
* @returns {Object} The corresponding heatmap location.
*/
HeatmapImageryProvider.prototype.mercatorPointToHeatmapPoint = function (point) {
var pn = {};
pn[this._options.xField] = Math.round((point.x - this._xoffset) / this._factor + this._spacing);
pn[this._options.yField] = Math.round((point.y - this._yoffset) / this._factor + this._spacing);
pn[this._options.yField] = this.height - pn[this._options.yField];
return pn;
};
/**
* Set an array of heatmap locations.
*
* @param {Number} min The minimum allowed value for the data points.
* @param {Number} max The maximum allowed value for the data points.
* @param {Array} data An array of data points with heatmap coordinates(x, y) and value
* @returns {Boolean} Wheter or not the data was successfully added or failed.
*/
HeatmapImageryProvider.prototype.setData = function (min, max, data) {
if (data && data.length > 0 && min !== null && min !== false && max !== null && max !== false) {
this._heatmap.setData({
min: min,
max: max,
data: data
});
return true;
}
return false;
};
/**
* Set an array of WGS84 locations.
*
* @param {Number} min The minimum allowed value for the data points.
* @param {Number} max The maximum allowed value for the data points.
* @param {Array} data An array of data points with WGS84 coordinates(x=lon, y=lat) and value
* @returns {Boolean} Wheter or not the data was successfully added or failed.
*/
HeatmapImageryProvider.prototype.setWGS84Data = function (min, max, data) {
if (data && data.length > 0 && min !== null && min !== false && max !== null && max !== false) {
var convdata = [];
for (var i = 0; i < data.length; i++) {
var gp = data[i];
var hp = this.wgs84PointToHeatmapPoint(gp);
var value = gp[this._options.valueField];
if (value) {
hp[this._options.valueField] = value;
}
convdata.push(hp);
}
return this.setData(min, max, convdata);
}
return false;
};
/**
* Gets the credits to be displayed when a given tile is displayed.
*
* @param {Number} x The tile X coordinate.
* @param {Number} y The tile Y coordinate.
* @param {Number} level The tile level;
* @returns {Credit[]} The credits to be displayed when the tile is displayed.
*
* @exception {DeveloperError} getTileCredits must not be called before the imagery provider is ready.
*/
HeatmapImageryProvider.prototype.getTileCredits = function (x, y, level) {
return undefined;
};
/**
* Requests the image for a given tile. This function should
* not be called before {@link HeatmapImageryProvider#ready} returns true.
*
* @param {Number} x The tile X coordinate.
* @param {Number} y The tile Y coordinate.
* @param {Number} level The tile level.
* @returns {Promise} A promise for the image that will resolve when the image is available, or
* undefined if there are too many active requests to the server, and the request
* should be retried later. The resolved image may be either an
* Image or a Canvas DOM object.
*
* @exception {DeveloperError} requestImage must not be called before the imagery provider is ready.
*/
HeatmapImageryProvider.prototype.requestImage = function (x, y, level) {
if (!this._ready) {
throw new Cesium.DeveloperError('requestImage must not be called before the imagery provider is ready.');
}
return this._image;
};
/**
* Picking features is not currently supported by this imagery provider, so this function simply returns
* undefined.
*
* @param {Number} x The tile X coordinate.
* @param {Number} y The tile Y coordinate.
* @param {Number} level The tile level.
* @param {Number} longitude The longitude at which to pick features.
* @param {Number} latitude The latitude at which to pick features.
* @return {Promise} A promise for the picked features that will resolve when the asynchronous
* picking completes. The resolved value is an array of {@link ImageryLayerFeatureInfo}
* instances. The array may be empty if no features are found at the given location.
* It may also be undefined if picking is not supported.
*/
HeatmapImageryProvider.prototype.pickFeatures = function () {
return undefined;
};
wutu3d.HeatmapImageryProvider = HeatmapImageryProvider;
})(window);