something about "Camera.ScreenToWorldPoint"

Unity Engine
1

hi ,everyone ,here is my code piece:

void FixedUpdate () {
        Vector3 rawPosition =Camera.main.ScreenToWorldPoint(Input.mousePosition);
        print (rawPosition);
    }

this script is attached to a simple cube.
here is the question:
the output is a fixed value instread of changing by movement of my mouse,could anyone tell me what happens?
by the way,that fixed value is the location of my MainCamera

2

No need to post twice: