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/*
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* Licensed to the Apache Software Foundation (ASF) under one
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* or more contributor license agreements. See the NOTICE file
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* distributed with this work for additional information
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* regarding copyright ownership. The ASF licenses this file
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* to you under the Apache License, Version 2.0 (the
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* "License"); you may not use this file except in compliance
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* with the License. You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing,
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* software distributed under the License is distributed on an
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* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
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* KIND, either express or implied. See the License for the
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* specific language governing permissions and limitations
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* under the License.
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*/
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/**
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* AUTO-GENERATED FILE. DO NOT MODIFY.
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*/
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/*
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* Licensed to the Apache Software Foundation (ASF) under one
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* or more contributor license agreements. See the NOTICE file
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* distributed with this work for additional information
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* regarding copyright ownership. The ASF licenses this file
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* to you under the Apache License, Version 2.0 (the
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* "License"); you may not use this file except in compliance
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* with the License. You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing,
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* software distributed under the License is distributed on an
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* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
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* KIND, either express or implied. See the License for the
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* specific language governing permissions and limitations
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* under the License.
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*/
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/* global Uint8ClampedArray */
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import { platformApi } from 'zrender/lib/core/platform.js';
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var GRADIENT_LEVELS = 256;
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var HeatmapLayer = /** @class */function () {
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function HeatmapLayer() {
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this.blurSize = 30;
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this.pointSize = 20;
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this.maxOpacity = 1;
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this.minOpacity = 0;
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this._gradientPixels = {
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inRange: null,
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outOfRange: null
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};
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var canvas = platformApi.createCanvas();
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this.canvas = canvas;
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}
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/**
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* Renders Heatmap and returns the rendered canvas
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* @param data array of data, each has x, y, value
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* @param width canvas width
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* @param height canvas height
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*/
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HeatmapLayer.prototype.update = function (data, width, height, normalize, colorFunc, isInRange) {
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var brush = this._getBrush();
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var gradientInRange = this._getGradient(colorFunc, 'inRange');
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var gradientOutOfRange = this._getGradient(colorFunc, 'outOfRange');
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var r = this.pointSize + this.blurSize;
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var canvas = this.canvas;
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var ctx = canvas.getContext('2d');
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var len = data.length;
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canvas.width = width;
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canvas.height = height;
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for (var i = 0; i < len; ++i) {
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var p = data[i];
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var x = p[0];
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var y = p[1];
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var value = p[2];
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// calculate alpha using value
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var alpha = normalize(value);
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// draw with the circle brush with alpha
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ctx.globalAlpha = alpha;
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ctx.drawImage(brush, x - r, y - r);
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}
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if (!canvas.width || !canvas.height) {
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// Avoid "Uncaught DOMException: Failed to execute 'getImageData' on
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// 'CanvasRenderingContext2D': The source height is 0."
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return canvas;
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}
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// colorize the canvas using alpha value and set with gradient
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var imageData = ctx.getImageData(0, 0, canvas.width, canvas.height);
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var pixels = imageData.data;
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var offset = 0;
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var pixelLen = pixels.length;
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var minOpacity = this.minOpacity;
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var maxOpacity = this.maxOpacity;
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var diffOpacity = maxOpacity - minOpacity;
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while (offset < pixelLen) {
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var alpha = pixels[offset + 3] / 256;
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var gradientOffset = Math.floor(alpha * (GRADIENT_LEVELS - 1)) * 4;
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// Simple optimize to ignore the empty data
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if (alpha > 0) {
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var gradient = isInRange(alpha) ? gradientInRange : gradientOutOfRange;
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// Any alpha > 0 will be mapped to [minOpacity, maxOpacity]
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alpha > 0 && (alpha = alpha * diffOpacity + minOpacity);
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pixels[offset++] = gradient[gradientOffset];
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pixels[offset++] = gradient[gradientOffset + 1];
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pixels[offset++] = gradient[gradientOffset + 2];
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pixels[offset++] = gradient[gradientOffset + 3] * alpha * 256;
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} else {
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offset += 4;
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}
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}
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ctx.putImageData(imageData, 0, 0);
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return canvas;
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};
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/**
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* get canvas of a black circle brush used for canvas to draw later
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*/
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HeatmapLayer.prototype._getBrush = function () {
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var brushCanvas = this._brushCanvas || (this._brushCanvas = platformApi.createCanvas());
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// set brush size
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var r = this.pointSize + this.blurSize;
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var d = r * 2;
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brushCanvas.width = d;
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brushCanvas.height = d;
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var ctx = brushCanvas.getContext('2d');
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ctx.clearRect(0, 0, d, d);
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// in order to render shadow without the distinct circle,
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// draw the distinct circle in an invisible place,
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// and use shadowOffset to draw shadow in the center of the canvas
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ctx.shadowOffsetX = d;
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ctx.shadowBlur = this.blurSize;
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// draw the shadow in black, and use alpha and shadow blur to generate
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// color in color map
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ctx.shadowColor = '#000';
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// draw circle in the left to the canvas
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ctx.beginPath();
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ctx.arc(-r, r, this.pointSize, 0, Math.PI * 2, true);
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ctx.closePath();
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ctx.fill();
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return brushCanvas;
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};
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/**
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* get gradient color map
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* @private
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*/
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HeatmapLayer.prototype._getGradient = function (colorFunc, state) {
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var gradientPixels = this._gradientPixels;
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var pixelsSingleState = gradientPixels[state] || (gradientPixels[state] = new Uint8ClampedArray(256 * 4));
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var color = [0, 0, 0, 0];
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var off = 0;
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for (var i = 0; i < 256; i++) {
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colorFunc[state](i / 255, true, color);
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pixelsSingleState[off++] = color[0];
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pixelsSingleState[off++] = color[1];
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pixelsSingleState[off++] = color[2];
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pixelsSingleState[off++] = color[3];
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}
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return pixelsSingleState;
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};
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return HeatmapLayer;
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}();
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export default HeatmapLayer;
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