Develop Reference

VR speedrun timer

I am working on a VR speedrun game and I need a timer. The timer doesn't need to be showed in the screen for the player, just on the map I made. It needs to start when the player (VR) passes a specific point and end when it reaches a different point. If anyone has an idea of how to make this work I would really appreciate it.

On the start line you could have an empty gameobject with a trigger collider on it, and in the OnTriggerEnter event you could start a Coroutine that keeps track of the time, and on the finish line you'd have another trigger collider that sets a flag and stops the timer.
Something along the lines of this should work:
using UnityEngine;
using System;
public class Player : MonoBehaviour {
private bool _isTimerStarted = false;
private float _timeElapsed = 0;
private void OnTriggerEnter(Collider other) {
if (other.gameObject.name.Equals("Start Line")) {
_isTimerStarted = true;
StartCoroutine(StartTimer());
} else if (other.gameObject.name.Equals("Finish Line") {
_isTimerStarted = false;
}
}
IEnumerator StartTimer() {
while (_isTimerStarted) {
_elapsedTime += Time.deltaTime;
yield return null;
}
yield break;
}
}
For this to work just make sure your player has a RigidBody attached or else no collision will be detected :)

If you want a "timer" as in "show the elapsed time since some event" you might take a look at Stopwatch
var sw = Stopwatch.StartNew();
...
Console.WriteLine(sw.Elapsed.ToString());
The stopwatch is primarily intended for performance measurements. But it is easy to use, so if it fits your use case you might as well make use of it, even if the resolution and accuracy is much greater than you need.

How to do if something happened make number - 1

I am trying to do when i destroy all boxes something happen.
My code is;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.SceneManagement;
public class destroy : MonoBehaviour
{
private string BALL_TAG = "ball";
public AudioClip coin;
public AudioSource src;
public float numBox = 120f;
public bool isDestroyed;
private void OnCollisionEnter2D(Collision2D collision)
{
if (collision.gameObject.CompareTag(BALL_TAG))
{
src.clip = coin;
src.Play();
Destroy(gameObject);
isDestroyed = true;
}
}
private void Update()
{
boxes();
}
public void boxes()
{
if(isDestroyed == true)
numBox -= 1f;
if(numBox == 119)
SceneManager.LoadScene("mainManu");
}
private IEnumerator Two()
{
yield return new WaitForSeconds(1f);
Destroy(gameObject);
}
}
But it doesn't work.
It is suppose to do when I broke 1 box it sends me to menu.
I think its problem in "numBox -= 1f;" because I don't know hot to make this.

I don't understand your code completely. So, I need to make some assumptions.
I think the Script is attached to the box and every box has this Script. I also think, that your player Shoots Ball. Those Balls have a collider with an ball tag.
There are multiple problems with your code.
The first one is, that your count variable, numBox, is saved in your destroy Script, which is placed on each box.
this means, that every Box is counting for itself.
You have to centralize this. There are multiple ways for doing this.
One way is to declare this variable as static(https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/static)
This is not best practice, but works.
A Better way is to have a Script on Your Player, which holds this number and every Box searches for this Script and change this number if it is destroyed.
The second big Problem is, that your are doing some really weird thing in your Update and the collision handling
First of all, you are setting isDestroyed to true. Then in your boxes method, which is called in every Frame, you are decrementing your numBox variable by one, if this is Destroyed is true.
So if your Box gets hit, you are decrementing every frame.
After that you are checking every frame if your numBox is 119
If so, you change the Scene.
This is the reason, why you are getting to your MainMenu after only one boy
This behaviour is very weird, because it is totally unnecessary. You can reduce your variable directly in in your OnCollisionEnter2D Method.
There are some little things, which can be improved.
When you are trying to play a Sound, you don't have to specify the AudioClip in code. You can assign this directly in Unity on the AudioSource Component via drag and drop. This makes your code simpler.
You are not calling the Two Coroutine. You've specified this Coroutine but don't call it.
//Script on Player
public class PlayerBoxDestroyManager:MonoBehaviour
{
public int StartBoxes = 120;
private int Boxes;
private void Start()
{
Boxes = StartBoxes;
}
public void DestroyBox()
{
//Reduce our Boxes count
//This is equal to Boxes -= 1
// Boxes = Boxes -1
Boxes--;
// If we have less or zero Boxes left, we End call our EndGame methode
if(Boxes <= 0)
{
EndGame();
}
}
private void EndGame()
{
// We change the Scene to the mainMenu
SceneManager.LoadScene("mainManu");
}
}
```
//Script on all Boxes
public class Box : MonoBehaviour
{
public string Balltag = "ball";
//Audio Source the Audio Clip has to be assigned in the Unity editor
public AudioSource Coin;
private void OnCollisionEnter2D(Collision2D collision)
{
//Check it colliding Object has the right Tag
if(collision.transform.tag == Balltag)
{
//Get the reference to the Player Script
PlayerBoxDestroyManager PBDM = FindObjectOfType<PlayerBoxDestroyManager>();
//We can now access the Destroy Box Methode
PBDM.DestroyBox();
//Play the sound
Coin.Play();
//If we destroy our Object now, the Sound would also be deletet.
//We want to hear the sound, so we have to wait, till the sound is finished.
StartCoroutine(WaitTillAudioIsFinished());
}
}
IEnumerator WaitTillAudioIsFinished()
{
//we wait till the sound is finished
while (Coin.isPlaying)
{
yield return null;
}
//if finished, we destroy the Gameobject
Destroy(gameObject);
}
}
I hope I helped you. If you have questions, feel free to ask.
And sorry for my English:)

Cannot use InvokeRepeating with method parameters. How do I work around this?

I'm trying to implement a damage over time system, but Unity keeps saying "Trying to Invoke method...Couldn't be Called." The method I want to call uses the parameters "Collider coll", but from my research you can't invoke if the method has said paremters.
Here is my code:
using UnityEngine;
using UnityEngine.SceneManagement;
using System.Collections;
public class DamageOverTime : MonoBehaviour
{
public int PHP; //PHP = Player Health from PlayerHealth.cs script.
public int Damage; //Amount of damage.
public int DamageOverTime; //Damage over time.
public float DamageInterval_DOT = .25f; //Damage interval for damage over time.
public string Level;
PlayerHealth player;
void Start()
{
player = GameObject.Find("Player").GetComponent<PlayerHealth>();
InvokeRepeating("OnTriggerEnter", DamageInterval_DOT, DamageInterval_DOT);
}
void Update()
{
PHP = GameObject.Find("Player").GetComponent<PlayerHealth>().PlayerHP;
if (PHP <= 0)
{
SceneManager.LoadScene(Level);
}
}
void OnTriggerEnter(Collider coll)
{
if (coll.gameObject.tag == "Player")
{
GameObject.Find("Player").GetComponent<PlayerHealth>().PlayerHP = PHP - Damage;
}
if (coll.gameObject.tag == "Ball")
{
gameObject.SetActive(false);
SceneManager.LoadScene(Level);
}
}
}
My goal is to get the OnTriggerEnter function to loop ever 1/4 of a second (or lower possibly). Current upon entering a collider my health is drained by 60% in about a second which is far too fast. How should I work around this?

You can't use InvokeRepeating with OnTriggerEnter, because it's a trigger, which means it will trigger once when entrance of its holder occured.
Also InvokeRepeating means that you want to keep repeating an action continously which is not the case here. You want your trigger to occur once and then remove health points over time.
Solution - Coroutine
Unity3D makes custom usage of IEnumerable and yield keyword called Coroutine that always returns an IEnumerator. How it works? It will return control on every yield there is in our Coroutine and then will go back to exact point where it gave back control instead of starting function execution from scratch.
Code:
void OnTriggerEnter(Collider coll)
{
if (coll.gameObject.tag == "Player")
{
StartCoroutine("DamageOverTimeCoroutine");
}
if (coll.gameObject.tag == "Ball")
{
gameObject.SetActive(false);
SceneManager.LoadScene(Level);
}
}
public IEnumerator DamageOverTimeCoroutine()
{
var dotHits = 0;
while (dotHits < 4)
{
//Will remove 1/4 of Damage per tick
GameObject.Find("Player").GetComponent<PlayerHealth>().PlayerHP -= Damage / 4;
dotHits++;
//Will return control over here
yield return new WaitForSeconds(DamageInterval_DOT);
//And then control is returned back here once 0.25s passes
}
}
There's of course room for improvement in this Coroutine. You can pass parameters to it, same as you can to any other method in C#. Also you can implement other invervals that are not hardcoded. Code above is just a simple example on how to deal with such scenarios.
For continous damage over time
public IEnumerator DamageOverTimeCoroutine()
{
var dotHits = 0;
var player = GameObject.Find("Player").GetComponent<PlayerHealth>();
while (true)
{
//Stop removing damage, player is dead already
if (player.PlayerHP <= 0)
yield break;
//Will remove 5 Damage per tick
player.PlayerHP -= 5;
dotHits++;
//Will return control over here
yield return new WaitForSeconds(DamageInterval_DOT);
//And then control is returned back here once 0.25s passes
}
}
To stop Coroutine somewhere else from code use StopCoroutine("DamageOverTimeCoroutine") to stop certain coroutine type or StopAllCoroutines() to stop all coroutines that are active now.

Making GameObject appear and disappear for a finite amount of time

I'm trying to make a GameObject appear and disappear for a finite amount of time (Lets put the time function aside for now).
Here's what I came out with:
using UnityEngine;
using System.Collections;
public class Enemy1Behavior : MonoBehaviour
{
// Use this for initialization
void Start ()
{
}
// Update is called once per frame
void Update ()
{
this.gameObject.SetActive(false); // Making enemy 1 invisible
Debug.Log("Update called");
DisappearanceLogic(gameObject);
}
private static void DisappearanceLogic(GameObject gameObject)
{
int num = 0;
while (num >= 0)
{
if (num % 2 == 0)
{
gameObject.SetActive(false);
}
else
{
gameObject.SetActive(true);
}
num++;
}
}
}
Now when I click the play button in Unity the program just don't respond, and I can only quit it from the task manager using End Task.
(And yes I know there a infinite loop in the method).
So I guess Im doing something wrong. What is the best way for making a Gameobject Blink/Flash/appear-disappear in Unity?
Thanks guys.

You are using an infinite loop which locks your Update() completely, because num will always be greater then 0.
So you could use InvokeRepeating (http://docs.unity3d.com/ScriptReference/MonoBehaviour.InvokeRepeating.html)
public GameObject gameobj;
void Start()
{
InvokeRepeating("DisappearanceLogic", 0, interval);
}
void DisappearanceLogic()
{
if(gameobj.activeSelf)
{
gameobj.SetActive(false);
}
else
{
gameobj.SetActive(true);
}
}
interval is a float - something like 1f 0.5f etc.

You can make animation for blinking etc - Animations in Mecanim. Appearing and disappearing you can achieve using gameObject.SetActive(true/false);. If you want to make something with time its better to use Coroutines or just Invoke with delay parameter - Invoke Unity Docs.

Make text appear for 5 seconds in Unity

So at the start of my scene in my Unity game I want text to appear for a few seconds. How would I do this?

you can Invoke a method after a certain amount of time like this. Place the script on the canvas and drag the text to the canvasText slot.
using UnityEngine;
using UnityEngine.UI;
public class CanvasScript : MonoBehaviour
{
public Text canvasText1;
void Start ()
{
Invoke("DisableText", 5f);//invoke after 5 seconds
}
void DisableText()
{
canvasText1.enabled = false;
}
}

http://answers.unity3d.com/questions/907707/need-text-to-display-after-5-seconds.html
#pragma strict
public var myText : GameObject; // Assign the text to this in the inspector
function Start() {
yield WaitForSeconds (5);
myText.SetActive( true ); // Enable the text so it shows
yield WaitForSeconds (5);
myText.SetActive( false ); // Disable the text so it is hidden
}
Thanks for the answer, works great for me!