targetControl.cs

using UnityEngine;
using System.Collections;

public class targetControl : MonoBehaviour
{
  public bool targetControlEnabled = true;
	public bool boost = false;
	public int boostCount;
// Use this for initialization
	void Start ()
	{
		boostCount = 0;
	}
// Update is called once per frame
	void Update ()
	{
		boost = (boostCount > 0);
		if (targetControlEnabled) {
			if (Input.GetKey ("left"))
				rigidbody.AddForce (-2000F, 0, 0);
			if (Input.GetKey ("right"))
				rigidbody.AddForce (2000F, 0, 0);
			if (Input.GetKey ("space") || Input.GetKey ("up"))
				rigidbody.AddForce (0, 42000F, 0);
		}
		if (Input.GetKey ("0") && boost) {
			rigidbody.AddForce (90000F, 0, 0);
			boostCount--;
		}
	}
	
	void OnTriggerEnter(Collider other){
		if (other.gameObject.tag == "boost") {
			Debug.Log("boosted");
			Debug.Log(other);
			boostCount++;
			Destroy (other.gameObject);
		}
	}
	
	void OnCollisionEnter (Collision collision)
	{
		if (collision.gameObject.tag == "floor") {
			targetControlEnabled = true;
		}
	}

	void OnCollisionExit (Collision collision)
	{
		if (collision.gameObject.tag == "floor") {
			targetControlEnabled = false;
		}
	}
}