Unity使用图片实现transform.LookAt功能

public GameObject target;

void Update()
{
transform.eulerAngles = LookTargetAngle(transform, target.transform.position);
}

Vector3 LookTargetAngle(Transform playerTrans, Vector3 targetPos)
{
float dx = targetPos.x - playerTrans.transform.position.x;
float dy = targetPos.y - playerTrans.transform.position.y;
float rotationZ = Mathf.Atan2(dy, dx) * 180 / Mathf.PI;
//得到最终的角度并且确保在 [0, 360) 这个区间内
rotationZ -= 90;
//获取增加的角度
float originRotationZ = playerTrans.eulerAngles.z;
float addRotationZ = rotationZ - originRotationZ;
//超过 180 度需要修改为负方向的角度
if (addRotationZ > 180)
{
addRotationZ -= 360;
}
//应用旋转
return new Vector3(0, 0, playerTrans.eulerAngles.z + addRotationZ);
}