Change light when in trigger and pressing "E" ?

Question

Hey everybody. I'm making a game that need a door to be unlocked using this "electricity box". When I come into the room the box's light is red, altough when I enter the trigger, the light turns green and the door unlocks. Everything there is ok.

But the problem is, that I want the light to turn green when I'm in the trigger and pressing E, not by just aproaching it.

Any help would be really nice. Thanks.

Oh and here is the script I got:

 function Start(){
 }
 
 //Activate the Main function when player is near the box
 function OnTriggerEnter(c:Collider)
     {
        if(c.gameObject.tag =="Player") 
  
     {
        light.color = Color.green;
        
        }
 }

Answer 1

I have also added a boolean switchActivated which you can use to check if true to activate other things :

Updated answer Player toggles light on/off while standing in the trigger zone.

 var soundTurnOff : AudioClip;
 var soundTurnOn : AudioClip;
 
 var playerInTrigger : boolean = false;
 var switchActivated : boolean = false;
 
 function Update()
 {
     // check the player is in the trigger zone
     if ( playerInTrigger )
     {
         // check for player input
         if ( Input.GetKeyDown( KeyCode.E ) )
         {
             // behaviour based on the state of switchActivated
             switch ( switchActivated )
             {
                 // if switchActivated == false, turn it ON
                 case false :
                     switchActivated = true;
                     
                     light.color = Color.green;
                     
                     audio.clip = soundTurnOn;
                     audio.Play();
                 break;
                 
                 // if switchActivated == true, turn it OFF
                 case true :
                     switchActivated = false;
                     
                     light.color = Color.red;
                     
                     audio.clip = soundTurnOff;
                     audio.Play();
                 break;
             }
         }
     }
 }
  
 function OnTriggerEnter(c:Collider)
 {
     if ( c.gameObject.tag == "Player" )
     {
         playerInTrigger = true;
     }
 }
  
 function OnTriggerExit(c:Collider)
 {
     if ( c.gameObject.tag == "Player" )
     {
         playerInTrigger = false;
     }
 }

// ------------------------------------------------------------------------------------

original answer that automatically turned off when player left the trigger.

 var soundTurnOff : AudioClip;
 var soundTurnOn : AudioClip;
 
 var playerInTrigger : boolean = false;
 var switchActivated : boolean = false;
 
 function Update()
 {
     if ( playerInTrigger && !switchActivated )
     {
         if ( Input.GetKeyDown( KeyCode.E ) )
         {
             switchActivated = true;
             
             light.color = Color.green;
             
             audio.clip = soundTurnOn;
             audio.Play();//It plays the TurnOn sound
         }
     }
     
     if ( !playerInTrigger && switchActivated )
     {
         switchActivated = false;
         
         light.color = Color.red;
         
         audio.clip = soundTurnOff;
         audio.Play(); //It plays TurnOff sound
     }
 }
  
 function OnTriggerEnter(c:Collider)
 {
     if ( c.gameObject.tag == "Player" )
     {
         playerInTrigger = true;
     }
 }
  
 function OnTriggerExit(c:Collider)
 {
     if ( c.gameObject.tag == "Player" )
     {
         playerInTrigger = false;
     }
 }

Answer 2

Answer by gdubrocks · May 11, 2014 at 06:04 AM

Right now your code activates any time your player enters the area.

You want to check if a key was pressed, so use Input.getKey()

 function OnTriggerEnter(c:Collider)
 {
    if(c.gameObject.tag =="Player") 
    {
        if (Input.GetKey ("e"))
        {
        light.color = Color.green;
        }
    }
 }

This explains it better http://docs.unity3d.com/Documentation/ScriptReference/Input.GetKey.html

Add comment · Show 5 · Share

poff · May 11, 2014 at 08:05 AM 0

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I tried your code, but for some wierd reason it doesn't work. I enter the trigger, the sound still plays, the door unlocks on it's own without me even pressing E. Here, I edited the script a bit:

 var soundTurnOff : AudioClip;
 var soundTurnOn : AudioClip;
 
 function Start(){
 }
 
 //Activate the $$anonymous$$ain function when player is near the box
 
 function OnTriggerEnter(c:Collider)
 {
        if(c.gameObject.tag =="Player"){ //If the player enters the trigger..
        audio.clip = soundTurnOn;
        audio.Play();//It plays the TurnOn sound     
        light.color = Color.green;
        } else { //If player is not in trigger...
        audio.clip = soundTurnOff;
        audio.Play(); //It plays TurnOff sound
        
 }
             }

AlucardJay · May 11, 2014 at 08:55 AM 0

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Never check for a key in a trigger/collision event. This has been covered many times before. Unless you are psychic or have amazing reflexes, the chance that you will press a key at the exact moment of the event is never.

@poff you never even added the input condition :/

have a boolean that is toggled by trigger enter/exit events, then in update check if the boolean is true and key is pressed down.

Scribe · May 11, 2014 at 11:03 AM 0

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@alucardj out of interest, is it okay to check key presses in OnTriggerStay or is this bad for performance reasons? P.S. Once I'm home I can check this myself so don't worry if you miss this.

AlucardJay · May 11, 2014 at 11:09 AM 0

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http://docs.unity3d.com/Documentation/ScriptReference/Input.html

Note also that the Input flags are not reset until "Update()", so its suggested you make all the Input Calls in the Update Loop.

As trigger events occur at different intervals to Update, it is not recommendable.

Scribe · May 11, 2014 at 11:18 AM 0

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Ok cool, that makes sense. Thanks!

Change light when in trigger and pressing "E" ?

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