unity实现点击鼠标左键 在屏幕位置创建物体

public void Update(){Vector3 mouse= Input.mousePosition;//获得鼠标屏幕坐标mouse.z = 15;//设置z值（相当于与摄像机之间的距离）Vector3 worldmouse = Camera.main.ScreenToWorldPoint(mouse);//获得屏幕的世界坐标if (Input.GetMouseButtonDown(0))//若点下鼠标右键{GameObject a = GameObject.CreatePrimitive(PrimitiveType.Sphere);//创建球体a.transform.position = worldmouse;//球体的世界坐标=鼠标世界坐标}}