code: function getArc(rx, ry, angle, largeArc, sweep, p0, p1) {
              var result = a2c(p0.x, p0.y, p1.x, p1.y, largeArc, sweep, rx, ry, angle);
              var path = [];
  
              if (result.length) {
                  path.push({
                      x: result[0][0],
                      y: result[0][1],
                      onCurve: true
                  });
  
                  // 将三次曲线转换成二次曲线
                  result.forEach(function (c, index) {
                      var q2Array = bezierCubic2Q2({
                          x: c[0],
                          y: c[1]
                      }, {
                          x: c[2],
                          y: c[3]
                      }, {
                          x: c[4],
                          y: c[5]
                      }, {
                          x: c[6],
                          y: c[7]
                      });
  
                      q2Array[0][2].onCurve = true;
                      path.push(q2Array[0][1]);
                      path.push(q2Array[0][2]);
                      if (q2Array[1]) {
                          q2Array[1][2].onCurve = true;
                          path.push(q2Array[1][1]);
                          path.push(q2Array[1][2]);
                      }
                  });
              }
  
              return path;
          }
docs: 获取椭圆弧度
  
  @param {number} rx 椭圆长半轴
  @param {number} ry 椭圆短半轴
  @param {number} angle 旋转角度
  @param {number} largeArc 是否大圆弧
  @param {number} sweep 是否延伸圆弧
  @param {Object} p0 分割点1
  @param {Object} p1 分割点2
  @return {Array} 分割后的路径