forked from SuperMap/iClient-JavaScript
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathHeatMap.js
More file actions
446 lines (405 loc) · 17.7 KB
/
HeatMap.js
File metadata and controls
446 lines (405 loc) · 17.7 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
/* Copyright© 2000 - 2018 SuperMap Software Co.Ltd. All rights reserved.
* This program are made available under the terms of the Apache License, Version 2.0
* which accompanies this distribution and is available at http://www.apache.org/licenses/LICENSE-2.0.html.*/
import ol from 'openlayers';
import {Util} from '../core/Util';
import {
GeoJSON as GeoJSONFormat,
GeometryVector,
ServerFeature,
CommonUtil,
LonLat,
GeometryPoint,
GeoText
} from '@supermap/iclient-common';
/**
* @class ol.source.HeatMap
* @classdesc 热力图层类。
* @category Visualization HeatMap
* @param {string} name - 图层名称
* @param {Object} options - 构造参数。
* @param {ol.Map} options.map - openlayers 的 map 对象。
* @param {string} [options.id] - 专题图层 ID，默认使用 CommonUtil.createUniqueID("HeatMapSource_") 创建专题图层 ID。
* @param {string} [options.featureWeight] - 对应 feature 属性中的热点权重字段名称，权重值类型为 float。
* @param {number} [options.radius=50] - 热点渲染的最大半径（热点像素半径），单位为 px，当 useGeoUnit 参数 为 true 时，单位使用当前图层地理坐标单位。热点显示的时候以精确点为中心点开始往四周辐射衰减，其衰减半径和权重值成比列。
* @param {boolean} [options.loadWhileAnimating=true] - 是否实时重绘。（当绘制大数据量要素的情况下会出现卡顿，建议把该参数设为 false）。
* @param {number} [options.opacity=1] - 图层透明度。
* @param {Array.<string>} [options.colors=['blue','cyan','lime','yellow','red']] - 颜色线性渐变数组，颜色值必须为 canvas 所支持的。
* @param {boolean} [options.useGeoUnit=false] - 使用地理单位，false 表示默认热点半径默认使用像素单位。当设置为 true 时，热点半径和图层地理坐标保持一致。
* @extends {ol.source.ImageCanvas}
*/
export class HeatMap extends ol.source.ImageCanvas {
constructor(name, opt_options) {
var options = opt_options ? opt_options : {};
super({
attributions: options.attributions || new ol.Attribution({
html: "Map Data <span>© <a href='http://support.supermap.com.cn/product/iServer.aspx' target='_blank'>SuperMap iServer</a></span> with <span>© <a href='http://iclient.supermap.io' target='_blank'>SuperMap iClient</a></span>"
}),
canvasFunction: canvasFunctionInternal_,
logo: options.logo,
projection: options.projection,
ratio: options.ratio,
resolutions: options.resolutions,
state: options.state
});
function canvasFunctionInternal_(extent, resolution, pixelRatio, size, projection) { // eslint-disable-line no-unused-vars
var mapWidth = size[0] * pixelRatio;
var mapHeight = size[1] * pixelRatio;
this.rootCanvas.width = this.maxWidth = mapWidth;
this.rootCanvas.height = this.maxHeight = mapHeight;
if (!this.features) {
return this.rootCanvas;
}
this.pixelRatio = pixelRatio;
//记录偏移量
var width = this.map.getSize()[0] * pixelRatio;
var height = this.map.getSize()[1] * pixelRatio;
this.offset = [(mapWidth - width) / 2 / pixelRatio, (mapHeight - height) / 2 / pixelRatio];
this.updateHeatPoints(resolution);
return this.rootCanvas;
}
//初始化成员变量
this.canvasFunctionInternal_ = canvasFunctionInternal_;
this.features = [];
this.name = name;
if (!options.map) {
throw new Error('options.map is not found.');
}
this.map = options.map;
// this.TFEvents = options.TFEvents || [];
this.id = options.id ? options.id : CommonUtil.createUniqueID("HeatMapSource_");
this.opacity = options.opacity ? options.opacity : 1;
this.colors = options.colors ? options.colors : ['blue', 'cyan', 'lime', 'yellow', 'red'];
this.useGeoUnit = options.useGeoUnit ? options.useGeoUnit : false;
this.radius = options.radius ? options.radius : 50;
this.featureWeight = options.featureWeight ? options.featureWeight : null;
this.maxWeight = null;
this.minWeight = null;
this.maxWidth = null;
this.maxHeight = null;
//创建热力图绘制面板
this.rootCanvas = document.createElement("canvas");
var mapSize = this.map.getSize();
this.rootCanvas.width = this.maxWidth = parseInt(mapSize[0]);
this.rootCanvas.height = this.maxHeight = parseInt(mapSize[1]);
CommonUtil.modifyDOMElement(this.rootCanvas, null, null, null,
null, null, null, this.opacity);
this.canvasContext = this.rootCanvas.getContext('2d');
}
/**
* @function ol.source.HeatMap.prototype.addFeatures
* @description 添加热点信息。
* @param {(GeoJSONObject|Array.<ol.Feature>)} features - 待添加的要素数组。
* @example
* var geojson = {
* "type": "FeatureCollection",
* "features": [
* {
* "type": "feature",
* "geometry": {
* "type": "Point", //只支持point类型
* "coordinates": [0, 0]
* },
* "properties": {
* "height": Math.random()*9,
* }
* }
* ]
* };
* var heatMapSource = new ol.source.HeatMap("heatMap",{"map": map});
* heatMapSource.addFeatures(geojson);
* map.addLayer(new ol.layer.Image({
* source: heatMapSource
* }));
*/
addFeatures(features) {
this.features = this.toiClientFeature(features);
//支持更新features，刷新底图
this.changed();
}
/**
* @function ol.source.HeatMap.prototype.setOpacity
* @description 设置图层的不透明度，取值 [0-1] 之间。
* @param {number} opacity - 不透明度。
*/
setOpacity(opacity) {
if (opacity !== this.opacity) {
this.opacity = opacity;
var element = this.rootCanvas;
CommonUtil.modifyDOMElement(element, null, null, null,
null, null, null, opacity);
if (this.map !== null) {
// this.dispatchEvent({type: 'changelayer', value: {layer: this, property: "opacity"}});
this.changed();
}
}
}
/**
* @function ol.source.HeatMap.prototype.updateHeatPoints
* @description 刷新热点图显示。
* @param {ol.LngLatBounds} resolution - 当前显示范围。
* @private
*/
updateHeatPoints(resolution) {
if (this.features && this.features.length > 0) {
this.convertFastToPixelPoints(resolution);
} else {
this.canvasContext.clearRect(0, 0, this.maxWidth, this.maxWidth);
}
}
/**
* @function ol.source.HeatMap.prototype.convertFastToPixelPoints
* @description 过滤位于当前显示范围内的热点，并转换其为当前分辨率下的像素坐标。
* @param {number} resolution - 当前分辨率。
* @private
*/
convertFastToPixelPoints(resolution) {
var data = [], x, y, k, maxTemp, minTemp, maxWeightTemp;
//热点半径
this.useRadius = this.useGeoUnit ? parseInt(this.radius / resolution) : this.radius;
for (var i = 0; i < this.features.length; i++) {
var feature = this.features[i];
var point = feature.geometry;
//过滤，只显示当前范围
// if (mapBounds.contains(point.x, point.y)) {
var pixelPoint = this.getLocalXY(new LonLat(point.x, point.y));
if (this.featureWeight) {
pixelPoint.weight = feature.attributes[this.featureWeight];//point.value;
if (!this.maxWeight) {
//找出最大最小权重值
maxTemp = maxTemp ? maxTemp : pixelPoint.weight;
minTemp = minTemp ? minTemp : pixelPoint.weight;
maxTemp = Math.max(maxTemp, pixelPoint.weight);
minTemp = Math.min(minTemp, pixelPoint.weight);
}
} else {
pixelPoint.weight = 1;
}
x = Math.floor(pixelPoint[0]);
y = Math.floor(pixelPoint[1]);
k = pixelPoint.weight;
data.push([x, y, k]);
// }
}
//无最大权重设置
if (!this.maxWeight) {
if (maxTemp && minTemp) {
maxWeightTemp = (maxTemp + minTemp) / 2;
} else {
maxWeightTemp = 1;
}
this.draw(data, maxWeightTemp);
} else {
this.draw(data, this.maxWeight);
}
}
/**
* @function ol.source.HeatMap.prototype.draw
* @description 绘制热点图。
* @param {Array} data - convertToPixelPoints 方法计算出的点。
* @param {number} maxWeight -最大权重。
* @private
*/
draw(data, maxWeight) {
if (this.maxHeight > 0 && this.maxWidth > 0) {
//清空
var ctx = this.canvasContext;
this.canvasContext.clearRect(0, 0, this.maxWidth, this.maxHeight);
this.drawCircle(this.useRadius);
this.createGradient();
for (var i = 0; i < data.length; i++) {
var p = data[i];
this.canvasContext.globalAlpha = Math.max(p[2] / maxWeight, 0.05);
this.canvasContext.drawImage(this.circle, p[0] - this.useRadius, p[1] - this.useRadius);
}
var colored = ctx.getImageData(0, 0, this.maxWidth, this.maxHeight);
this.colorize(colored.data, this.grad);
ctx.putImageData(colored, 0, 0);
} else {
return false;
}
}
/**
* @function ol.source.HeatMap.prototype.colorize
* @description 根据渐变色重置热点图 rgb 值。
* @param {Object} pixels - 像素 rgba 值。
* @param {Array} gradient - 渐变 canvas.getImageData.data。
* @private
*/
colorize(pixels, gradient) {
for (var i = 0, j; i < pixels.length; i += 4) {
j = pixels[i + 3] * 4;
if (j) {
pixels[i] = gradient[j];
pixels[i + 1] = gradient[j + 1];
pixels[i + 2] = gradient[j + 2];
}
}
}
/**
* @function ol.source.HeatMap.drawCircle
* @description 绘制热点半径圆。
* @param {number} r - 热点半径。
* @private
*/
drawCircle(r) {
var blur = r / 2;
var circle = this.circle = document.createElement('canvas'),
ctx = circle.getContext("2d");
circle.height = 2 * r;
circle.width = 2 * r;
ctx.shadowOffsetX = ctx.shadowOffsetY = 2 * r;
ctx.shadowBlur = blur;
ctx.shadowColor = "#000000";
ctx.beginPath();
ctx.arc(-r, -r, r / 2, 0, Math.PI * 2, true);
ctx.closePath();
ctx.fill();
}
/**
* @function ol.source.HeatMap.createGradient
* @description 根据 this.canvasColors 设置渐变并 getImageData。
* @private
*/
createGradient() {
var colors = this.colors;
var canvas = document.createElement('canvas'),
ctx = canvas.getContext("2d"),
gradient = ctx.createLinearGradient(0, 0, 0, 256);
canvas.height = 256;
canvas.width = 1;
var index = 1;
for (var i = 0, len = colors.length; i < len; i++) {
gradient.addColorStop(index / len, colors[i]);
index++;
}
ctx.fillStyle = gradient;
ctx.fillRect(0, 0, 1, 256);
this.grad = ctx.getImageData(0, 0, 1, 256).data;
}
/**
* @function ol.source.HeatMap.prototype.getLocalXY
* @description 获取坐标系统。
* @param {Object} coordinate - 坐标位置。
*/
getLocalXY(coordinate) {
var pixelP, map = this.map;
if (coordinate instanceof GeometryPoint || coordinate instanceof GeoText) {
pixelP = map.getPixelFromCoordinate([coordinate.x, coordinate.y]);
}
if (coordinate instanceof LonLat) {
pixelP = map.getPixelFromCoordinate([coordinate.lon, coordinate.lat]);
}
var rotation = -map.getView().getRotation();
var center = map.getPixelFromCoordinate(map.getView().getCenter());
var rotatedP = pixelP;
if (this.pixelRatio) {
rotatedP = this.scale(pixelP, center, this.pixelRatio);
}
if (pixelP && center) {
rotatedP = this.rotate(rotatedP, rotation, center);
}
if (this.offset && rotatedP) {
return [rotatedP[0] + this.offset[0], rotatedP[1] + this.offset[1]];
}
return rotatedP;
}
/**
* @function ol.source.HeatMap.prototype.rotate
* @description 获取某像素坐标点 pixelP 绕中心 center 逆时针旋转 rotation 弧度后的像素点坐标。
* @param {number} pixelP - 像素坐标点位置。
* @param {number} rotation - 旋转角度。
* @param {number} center - 中心位置。
*/
rotate(pixelP, rotation, center) {
var x = Math.cos(rotation) * (pixelP[0] - center[0]) - Math.sin(rotation) * (pixelP[1] - center[1]) + center[0];
var y = Math.sin(rotation) * (pixelP[0] - center[0]) + Math.cos(rotation) * (pixelP[1] - center[1]) + center[1];
return [x, y];
}
/**
* @function ol.source.HeatMap.prototype.scale
* @description 获取某像素坐标点 pixelP 相对于中心 center 进行缩放 scaleRatio 倍后的像素点坐标。
* @param {Object} pixelP - 像素点。
* @param {Object} center - 中心点。
* @param {number} scaleRatio - 缩放倍数。
* @returns {Array.<number>} 返回数组形比例
*/
scale(pixelP, center, scaleRatio) {
var x = (pixelP[0] - center[0]) * scaleRatio + center[0];
var y = (pixelP[1] - center[1]) * scaleRatio + center[1];
return [x, y];
}
/**
* @function ol.source.HeatMap.prototype.removeFeatures
* @description 移除指定的热点信息。
* @param {Array.<SuperMap.Feature.Vector>} features - 热点信息数组。
*/
removeFeatures(features) {
if (!features || features.length === 0 || !this.features || this.features.length === 0) {
return;
}
if (features === this.features) {
return this.removeAllFeatures();
}
if (!(CommonUtil.isArray(features))) {
features = [features];
}
var heatPoint, index, heatPointsFailedRemoved = [];
for (var i = 0, len = features.length; i < len; i++) {
heatPoint = features[i];
index = CommonUtil.indexOf(this.features, heatPoint);
//找不到视为删除失败
if (index === -1) {
heatPointsFailedRemoved.push(heatPoint);
continue;
}
//删除热点
this.features.splice(index, 1);
}
var succeed = heatPointsFailedRemoved.length == 0 ? true : false;
//派发删除features成功的事件
this.dispatchEvent({type: 'featuresremoved', value: {features: heatPointsFailedRemoved, succeed: succeed}});
this.changed();
}
/**
* @function ol.source.HeatMapprototype.removeAllFeatures
* @description 移除全部的热点信息。
*/
removeAllFeatures() {
this.features = [];
this.changed();
}
/**
* @function ol.source.HeatMap.prototype.toiClientFeature
* @description 转为 iClient 要素。
* @param {GeoJSONObject|Array.<ol.Feature>} features - 待添加的要素数组。
* @returns {SuperMap.Feature.Vector} 转换后的 iClient 要素
*/
toiClientFeature(features) {
if (!Util.isArray(features)) {
features = [features];
}
let featuresTemp = [], geometry, attributes;
for (let i = 0, len = features.length; i < len; i++) {
if (features[i] instanceof ol.Feature) {
//热点图支支持传入点对象要素
if (features[i].getGeometry() instanceof ol.geom.Point) {
geometry = new GeometryPoint(features[i].getGeometry().getCoordinates()[0], features[i].getGeometry().getCoordinates()[1]);
//固定属性字段为 "Properties"
attributes = features[i].getProperties()["Properties"] ? features[i].getProperties()["Properties"] : {};
featuresTemp.push(new GeometryVector(geometry, attributes));
}
} else if (["FeatureCollection", "Feature", "Geometry"].indexOf(features[i].type) != -1) {
let format = new GeoJSONFormat();
featuresTemp = featuresTemp.concat(format.read(features[i]));
} else if (features[i].geometry && features[i].geometry.parts) {
//iServer服务器返回数据格式
featuresTemp.push(ServerFeature.fromJson(features[i]).toFeature());
} else {
throw new Error(`Features[${i}]'s type does not match, please check.`);
}
}
return featuresTemp;
}
}
ol.source.HeatMap = HeatMap;