Mathf.Clamp01

public static float Clamp01 (float value);

설명

Clamps value between 0 and 1 and returns value.

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour {
    void Update() {
        transform.position = new Vector3(Mathf.Clamp01(Time.time), 0, 0);
    }
}