求助，关于射线的碰撞检测

Ray mRay = Camera.main.ScreenPointToRay(Input.mousePosition);
RaycastHit mHit;
//判断射线是否击中地面
if(Physics.Raycast(mRay,out mHit))
{
if(mHit.collider.gameObject.tag == "Terrain")
{
//获取目标坐标
mTargetPos = new Vector3(mHit.point.x,mHit.point.y + 0.5f,mHit.point.z);
//让主角面朝目标坐标
shapeTransform.LookAt(mTargetPos);
}
}
if(Input.GetMouseButton(0))
{
if (attackTimer > 0)
attackTimer -= Time.deltaTime;
if (attackTimer < 0)
attackTimer = 0;
if(attackTimer == 0)
{
Ray shotRay = new Ray(mTargetPos,priringPoint.position);
Debug.DrawLine (mTargetPos,priringPoint.position,Color.yellow);
RaycastHit shotHit;
if(Physics.Raycast(shotRay,out shotHit))
{
if(shotHit.collider.gameObject.tag == "Enemy")
{
//获取敌对目标
EnemyAI enemy = (EnemyAI)shotHit.collider.GetComponent("EnemyAI");
enemy.AddjustCurrenHealth(-10);
}
}
attackTimer = coolDown;
}
}

// 获取鼠标点击 屏幕的 位置
Ray mRay = Camera.main.ScreenPointToRay(Input.mousePosition);
RaycastHit mHit;
//判断射线是否击中地面
if(Physics.Raycast(mRay,out mHit))
{
if(mHit.collider.gameObject.tag == "Terrain")
{
//获取目标坐标
mTargetPos = new Vector3(mHit.point.x,mHit.point.y + 0.5f,mHit.point.z);
//让主角面朝目标坐标
shapeTransform.LookAt(mTargetPos);
}
}
// 发射 射线的代码 ， 方向点 是鼠标点击屏幕的位置 ，起点是模型 ，
if(Input.GetMouseButton(0))
{
if (attackTimer > 0)
attackTimer -= Time.deltaTime;
if (attackTimer < 0)
attackTimer = 0;
if(attackTimer == 0)
{
Ray shotRay = new Ray(mTargetPos,priringPoint.position);
Debug.DrawLine (mTargetPos,priringPoint.position,Color.yellow);
RaycastHit shotHit;
if(Physics.Raycast(shotRay,out shotHit))
{
if(shotHit.collider.gameObject.tag == "Enemy")
{
//获取敌对目标
EnemyAI enemy = (EnemyAI)shotHit.collider.GetComponent("EnemyAI");
enemy.AddjustCurrenHealth(-10);
}
}
attackTimer = coolDown;
}
}