如何实现一个带圆弧角度的圆环

话不多说，先上图

 

 vue实现代码

<template>
  <div class="raw-circle circle">
    <div class="circle__wrap">
      <!-- 左半边 -->
      <div class="circle__half-left">
        <div class="circle__half-left-deg"
             :style="degreeStyle.halfLeft"></div>
      </div>
      <!-- 右半边 -->
      <div class="circle__half-right">
        <div class="circle__half-right-deg"
             :style="degreeStyle.halfRight"></div>
      </div>
      <!-- 中心圆 -->
      <div class="circle__center"></div>
      <!-- 指针臂 -->
      <!-- 开头固定圆弧 -->
      <div class="circle__long-arm circle__long-arm-start">
        <div class="circle__long-arm-point"></div>
      </div>
      <!-- 动态结尾圆弧 -->
      <div class="circle__long-arm"
           :style="degreeStyle.arm">
        <div class="circle__long-arm-point"></div>
      </div>
    </div>
  </div>
</template>

<script>
export default {
  name: 'RawCircle',
  data () {
    return {
      rate: 65
    }
  },
  computed: {
    degreeStyle () {
      let armDeg = 0
      let halfRightDeg = 0
      let halfLeftDeg = 0

      armDeg = 360 * this.rate / 100
      halfRightDeg = this.rate > 50 ? 180 : 360 * this.rate / 100
      halfLeftDeg = this.rate < 50 ? 0 : 360 * (this.rate - 50) / 100

      return {
        arm: {
          transform: `rotate(${armDeg}deg)`
        },
        halfRight: {
          transform: `rotate(${halfRightDeg}deg)`
        },
        halfLeft: {
          transform: `rotate(${halfLeftDeg}deg)`
        }
      }
    }
  }
}
</script>

<style scoped>
/** @define circle; weak */

.circle {
  align-items: center;
  background-color: #2b335a;
  border-radius: 16px;
  margin-top: 40px;
  padding: 40px 0;
  width: 750px;
}

.circle__wrap {
  background-color: #2b335a;
  border-radius: 120px;
  height: 240px;
  overflow: hidden;
  position: relative;
  width: 240px;
}

.circle__center {
  background-color: #2b335a;
  border-radius: 100px;
  height: 200px;
  left: 20px;
  position: absolute;
  top: 20px;
  width: 200px;
}

.circle__long-arm {
  background-color: rgba(32, 178, 170, 0);
  height: 120px;
  left: 110px;
  position: absolute;
  top: 0;
  transform-origin: 10px 120px;
  width: 20px;
}

.circle__long-arm-start {
  transform: rotate(0deg);
}

.circle__long-arm-point {
  background-color: #f95064;
  border-radius: 10px;
  height: 20px;
  left: 0;
  position: absolute;
  top: 0;
  width: 20px;
}

.circle__half-right {
  background-color: #f95064;
  border-radius: 0 120px 120px 0;
  height: 240px;
  overflow: hidden;
  position: absolute;
  right: 0;
  top: 0;
  width: 120px;
}

.circle__half-right-deg {
  background-color: #1d1d33;
  height: 240px;
  transform-origin: left center;
  width: 120px;
}

.circle__half-left {
  background-color: #f95064;
  border-radius: 120px 0 0 120px;
  height: 240px;
  left: 0;
  overflow: hidden;
  position: absolute;
  top: 0;
  width: 120px;
}

.circle__half-left-deg {
  background-color: #1d1d33;
  height: 240px;
  transform-origin: right center;
  width: 120px;
}

</style>