JavaScript实现绘制两个坐标之间的连线

const midX = (x1 + x2) / 2;
const midY = (y1 + y2) / 2;

  const a = x2 -x1;
  const b = y2 - y1;
  const length = Math.sqrt(a * a + b * b);

  const a = x2 -x1;
  const b = y2 - y1;
  const c = (180 * Math.atan2(b, a)) / Math.PI;

export const drawLine = (startObj, endObj) => {
    // 起点坐标
    const startY = startObj.y;
    const startX = startObj.x;

    // 终点坐标
    const endY = endObj.y;
    const endX = endObj.x;

    // 用勾股定律计算出斜边长度及其夹角（即连线的旋转角度）
    const a = endX - startX;
    const b = endY - startY;
    // 计算连线长度
    const length = Math.sqrt(a * a + b * b);
    // 弧度值转换为角度值
    const c = (180 * Math.atan2(b, a)) / Math.PI;

    // 连线中心坐标
    const midX = (endX + startX) / 2;
    const midY = (endY + startY) / 2;
    const deg = c <= -90 ? 360 + c : c; // 负角转换为正角

    return {
        position: 'fixed',
        top: `${midY}px`,
        left: `${midX - length / 2}px`,
        width: `${length}px`,
        transform: `rotate(${deg}deg)`,
    };
};