import React, { PureComponent } from 'react'; import autoHeight from '../autoHeight'; import styles from './index.less'; /* eslint no-return-assign: 0 */ /* eslint no-mixed-operators: 0 */ // riddle: https://riddle.alibaba-inc.com/riddles/2d9a4b90 @autoHeight() export default class WaterWave extends PureComponent { state = { radio: 1, }; componentDidMount() { requestAnimationFrame(() => { this.renderChart(); this.resize(); }); window.addEventListener('resize', this.resize, { passive: true }); } componentWillUnmount() { cancelAnimationFrame(this.timer); if (this.node) { this.node.innerHTML = ''; } window.removeEventListener('resize', this.resize); } resize = () => { requestAnimationFrame(() => { if (this.root) { const { height } = this.props; const { offsetWidth } = this.root.parentNode; this.setState({ radio: offsetWidth < height ? offsetWidth / height : 1, }); } }); }; renderChart() { const { percent, color = '#1890FF' } = this.props; const data = percent / 100; const self = this; if (!this.node || !data) { return; } const canvas = this.node; const ctx = canvas.getContext('2d'); const canvasWidth = canvas.width; const canvasHeight = canvas.height; const radius = canvasWidth / 2; const lineWidth = 2; const cR = radius - lineWidth; ctx.beginPath(); ctx.lineWidth = lineWidth * 2; const axisLength = canvasWidth - lineWidth; const unit = axisLength / 8; const range = 0.2; // 振幅 let currRange = range; const xOffset = lineWidth; let sp = 0; // 周期偏移量 let currData = 0; const waveupsp = 0.005; // 水波上涨速度 let arcStack = []; const bR = radius - lineWidth; const circleOffset = -(Math.PI / 2); let circleLock = true; for (let i = circleOffset; i < circleOffset + 2 * Math.PI; i += 1 / (8 * Math.PI)) { arcStack.push([radius + bR * Math.cos(i), radius + bR * Math.sin(i)]); } const cStartPoint = arcStack.shift(); ctx.strokeStyle = color; ctx.moveTo(cStartPoint[0], cStartPoint[1]); function drawSin() { ctx.beginPath(); ctx.save(); const sinStack = []; for (let i = xOffset; i <= xOffset + axisLength; i += 20 / axisLength) { const x = sp + (xOffset + i) / unit; const y = Math.sin(x) * currRange; const dx = i; const dy = 2 * cR * (1 - currData) + (radius - cR) - unit * y; ctx.lineTo(dx, dy); sinStack.push([dx, dy]); } const startPoint = sinStack.shift(); ctx.lineTo(xOffset + axisLength, canvasHeight); ctx.lineTo(xOffset, canvasHeight); ctx.lineTo(startPoint[0], startPoint[1]); const gradient = ctx.createLinearGradient(0, 0, 0, canvasHeight); gradient.addColorStop(0, '#ffffff'); gradient.addColorStop(1, '#1890FF'); ctx.fillStyle = gradient; ctx.fill(); ctx.restore(); } function render() { ctx.clearRect(0, 0, canvasWidth, canvasHeight); if (circleLock) { if (arcStack.length) { const temp = arcStack.shift(); ctx.lineTo(temp[0], temp[1]); ctx.stroke(); } else { circleLock = false; ctx.lineTo(cStartPoint[0], cStartPoint[1]); ctx.stroke(); arcStack = null; ctx.globalCompositeOperation = 'destination-over'; ctx.beginPath(); ctx.lineWidth = lineWidth; ctx.arc(radius, radius, bR, 0, 2 * Math.PI, 1); ctx.beginPath(); ctx.save(); ctx.arc(radius, radius, radius - 3 * lineWidth, 0, 2 * Math.PI, 1); ctx.restore(); ctx.clip(); ctx.fillStyle = '#1890FF'; } } else { if (data >= 0.85) { if (currRange > range / 4) { const t = range * 0.01; currRange -= t; } } else if (data <= 0.1) { if (currRange < range * 1.5) { const t = range * 0.01; currRange += t; } } else { if (currRange <= range) { const t = range * 0.01; currRange += t; } if (currRange >= range) { const t = range * 0.01; currRange -= t; } } if (data - currData > 0) { currData += waveupsp; } if (data - currData < 0) { currData -= waveupsp; } sp += 0.07; drawSin(); } self.timer = requestAnimationFrame(render); } render(); } render() { const { radio } = this.state; const { percent, title, height } = this.props; return (
(this.root = n)} style={{ transform: `scale(${radio})` }} >
(this.node = n)} width={height * 2} height={height * 2} />
{title && {title}}

{percent}%

); } }