Input.GetKeyUp Help (C#)

I would just like to confirm one thing, will "It will not return true until the user has pressed the key and released it"? (quoted from http://docs.unity3d.com/ScriptReference/Input.GetKeyUp.html) or does it return true even just when the player lets the button go. I would just like to know because if that's the case then my code should work.

 

Just out of curiosity, when is he going to press it? During scene load?

 

In the update method

 

Hmm... so for the user/player to release the key he first has to press it?

 

It will return true at the time you release
the key only..i.e it remains false all the time
but becomes true just when you release the key
and then again immediately in the next frame it becomes false again.

 

It's not possible to let go of a button unless you have pressed it first. That's #3 in the Fundamental Laws of How Keyboards Work.

If you're trying to do this:

Code (csharp):

1. if(Input.GetKeyDown(KeyCode.someKey)) {
2.     if(Input.GetKeyUp(KeyCode.someKey)) {
3.         foo.DoTheBar();
4.     }
5. }

It won't work - a key isn't both down and up on the same frame. It might be physically possible if you have really fast fingers, but I'm pretty sure that either the OS or Unity spreads those two events out over time.

 

Question how do you make that little box for the code?

Ok well I had that and I figured it wouldn't work so I went with just:

1. if(Input.GetKeyUp(KeyCode.someKey)) {
2. //code
3. }

but that didnt seems to work either, Im not at home right now and can't check the code but I will reply my code when i do.

 

You get the box from clicking "insert -> code".

Input.GetKeyUp works, so it's definitely a bug in your code somewhere. It's easier to help if you actually post it.

 

Ok Thanks I get put the code up later today

 

This is the part of the code that isn't working, I want it to update the variable but It stay's the same

Code (CSharp):

1.  
2. using UnityEngine;
3. using System.Collections;
4.  
5. public class VariableChangeTest : MonoBehaviour {
6.     public int Side = 1;
7.     void FixedUpdate () {
8.         if( Input.GetKeyUp(KeyCode.Comma) == true && Side == 1 ) {
9.             Side = 2;
10.         }
11.     }
12. }
13.  

EDIT: Does it matter whether I use fixed update or a normal update ( I heard fixed update is better )

 

Clearly you are not a tester
What if I take the focus off the game, press the key, return focus to the game, and then release the key?
Players tend to try many things to break the game y'know.

 

Wait, so is there something wrong with the code?

 

GetKeyUp/Down changes every Update frame. This means that they are not reliable in FixedUpdate. Try to do the same thing in Update, and it'll be fine.

if you need to react to the input in FixedUpdate, poll the input in Update, and store some bool that you read in fixed:

Code (CSharp):

1. public int side = 1;
2. public int side = 1;
3.  
4. void Update() {
5.     if(Input.GetKeyUp(KeyCode.Comma)
6.         commaUnpressed = true;
7. }
8.  
9. void FixedUpdate() {
10.     if(commaUnpressed) {
11.         commaUnpressed = false;
12.         side = 2;
13.     }
14. }

 

FixedUpdate is used for physics-related calculations, since you'd want it to work in fixed intervals.
That would mean that if someone leaves and presses a key again, the actions may fall on times that the FixedUpdate was not there to catch these commands.

 

Ok Thanks, I'll test it

 

Ok it still dosn't work, but here's by full code (Pretty much i just want this camera to rotate around a 7x7 cube)

Code (CSharp):

1.  
2. using UnityEngine;
3. using System.Collections;
4.  
5. public class CameraControl1 : MonoBehaviour {
6.     public int Side = 1;
7.     void Update () {
8.         if( Input.GetKeyUp(KeyCode.Z) == true && Side == 1 ) {
9.             transform.Translate(-4,0,+4);
10.             Side = 2;
11.         }
12.         if( Input.GetKeyUp(KeyCode.Z) == true) {
13.             transform.Translate(+4,0,+4);
14.             Side = 3;
15.         }
16.         if( Input.GetKeyUp(KeyCode.Z) == true) {
17.             transform.Translate(+4,0,-4);
18.             Side = 4;
19.         }
20.         if( Input.GetKeyUp(KeyCode.Z) == true) {
21.             transform.Translate(-4,0,-4);
22.             Side = 1;
23.         }
24.     }
25. }
26.  

 

At first glance I can say one thing : All of your if clauses are going to run simultaneously when the Z
key is lifted.

Maybe, you wanted to add a && side == x etc in each of the if clause ?

 

ugh.. all those useless if statements...

Code (csharp):

1. void Update() {
2.   if (Input.GetKeyUp(KeyCode.Z)) {
3.     //do things
4.     switch(Side) {
5.       case 1: //do things
6.       case 2: //do things
7.     }
8.   }

 

Yeh, your right, I should add that, I just did so much fiddling I forgot to add it in

 

Still ugly ! You should use break with switch statements (otherwise your code will continue to check all cases).

Code (CSharp):

1. public class CameraControl1 : MonoBehaviour {
2.     public int Side = 0;
3.  
4.     private Vector3[] sideVectors = new Vector3[4];
5.  
6.     void Awake() {
7.         sideVectors[0] = new Vector3(-4, 0, 4);
8.         sideVectors[1] = new Vector3(4, 0, 4);
9.         sideVectors[2] = new Vector3(4, 0, -4);
10.         sideVectors[3] = new Vector3(-4, 0, -4);
11.     }
12.  
13.     void Update () {
14.         if(Input.GetKeyUp(KeyCode.Z) == true) {
15.             transform.Translate(sideVectors[Side]);
16.             Side++;
17.  
18.             if (Side >= sideVectors.Length) {
19.                 Side = 0;
20.             }
21.         }
22.     }
23. }

/codeBattle

 

You can't even use a switch without break statement..(will through compiler error) so it was kind off implied

 

It's quite possible when the frame rate is low due to whatever reasons. It's easy to simulate:

Code (csharp):

1.     void Start()
2.     {
3.         Application.targetFrameRate = 1;
4.         QualitySettings.vSyncCount = 0;
5.     }
6.  
7.     void Update()
8.     {
9.         if (Input.GetKeyDown(KeyCode.Alpha7))
10.         {
11.             Debug.Log("7 is down");
12.             if (Input.GetKeyUp(KeyCode.Alpha7))
13.             {
14.                 Debug.Log("7 is up");
15.             }
16.         }
17.     }
18.  

 

Um, Im still fairly new to all this so that's a tad confusing