OverlapCircle won't find player - c#

I've been trying to give to the NPCs of a game I'm working on the ability to "sense" when the Player is near. I've made this script and, for reasons unknown, the bool "found" stays false and, when I automatically set it to true, it reverts back to false (it still sends the player position to the goTo script, so at least that works). Does anyone know how to resolve this?
public class NPCLookForPlayerScript : MonoBehaviour {
public bool found; //player found
public float awareness; //how large is the circlecast
public int keepLooking; //for how much time, after losing sight of the player, he tries to keep on looking for him
public GameObject player; //variable to lock on to the player
int timer; //variable to decrement while player isn't in line of sight
NPCGoToScript goTo;
// Use this for initialization
void Start () {
goTo = GetComponent<NPCGoToScript>();
}
// Update is called once per frame
void Update () {
//he's always looking for the player
Collider2D coll = Physics2D.OverlapCircle((Vector2)transform.position, awareness);
//if the player is found, keep looking for him
if (coll.gameObject == player)
{
found = true;
timer = keepLooking;
}
//if the player was found,
if (found)
{
timer = timer - 1; //less time to look for the player
goTo.newPosition(player.transform.position);
}
//if the player is out of sight for too much time, stop looking for him
if (timer <= 0)
{
found = false;
}
}
void OnDrawGizmos()
{
Gizmos.color = Color.green;
Gizmos.DrawWireSphere((Vector2)transform.position, awareness);
}
}
Since someone has made me notice that the values of the variables aren't written in the code, let me be clear: I'm working on unity, this script has public values that can be modified by the inspector, which is very usefull since this script has to be used for different kinds of NPCs. So the values are not zero. awareness = 5f and keepLooking = 20. The player field does have the player GameObject.

You are never setting initial values for any of your fields :).
timer is declared but never set to anything so essentially it equals 0. Also awareness (your radius) is never set either so is 0.0f by default.
So your code...
Executes the Physics2D.OverlapCircle with a radius of zero (i.e. no circle)
Skips the logic in the coll == player statement cause there is no circle to collide with the player.
Skips the logic in the found statement cause found of false
Then executes the logic in the timer <= 0 statement cause the timer is 0 (was never defined)
Continues to set found to false every frame, forever and ever and ever, into the long good night
The player getting the the transform data should only happen whe you manually set found to true in the inspector and then only for one frame cause it reverts back to false in the very next statement.
You need to give your fields value greater than 0.

Related

why is there no scene transition using this code? (unity C# question with Scene manager)

I figured out the issue with a previous question on here, but now it's still not working.
Luckily I think I have figured out the issue. It's not detecting that an enemy has been killed/destroyed.
The way I have my code set up is that when an enemy is out of health the object is deactivated. But I assumed it would detect when an instance of the object was deactivated. But apparently not (at least from what I have seen).
I think that the best course of action is to make my enemy's "death script" connected to my win condition in some way (unless that isn't the proper way to go about it, in which case let me know what that proper action is).
I assume it would be to make the enemies variable global, but I am uncertain of how to do that or if it would even work for certain.
To reiterate, I am completely new to C# and unity, so if its solution is obvious or if the question is just stupid, remember that I have no clue where to go from this point (which is why this question is being created in the first place). If there is an existing question that can address this please link it, otherwise, anything helps.
here is the code for the win condition
public class GameWinner : MonoBehaviour
{
public GameObject[] enemies;
public Font font;
void OnTriggerEnter(Collider other)
{
enemies = GameObject.FindGameObjectsWithTag("Enemy"); // Checks if enemies are available with tag "Enemy". Note that you should set this to your enemies in the inspector.
if (enemies == null)
{
SceneManager.LoadScene(2);
}
}
}
here is the code for enemy destruction (note, this was ripped from a tutorial, specifically "let's try shooter", let me know if it would be beneficial to rework it completely)
public class ShootableBox : MonoBehaviour
{
//The box's current health point total
public int currentHealth = 3;
public void Damage(int damageAmount)
{
//subtract damage amount when Damage function is called
currentHealth -= damageAmount;
//Check if health has fallen below zero
if (currentHealth <= 0)
{
//if health has fallen below zero, deactivate it
gameObject.SetActive (false);
}
}
}
There's a difference between an empty array, and a null reference.
In your case, you should check to see if the array is empty:
enemies = GameObject.FindGameObjectsWithTag("Enemy"); // Checks if enemies are available with tag "Enemy". Note that you should set this to your enemies in the inspector.
if (enemies.Length == 0)
SceneManager.LoadScene(2);

Keyboard input works on some occasions but not others

So, I've been trying to learn Unity these past couple of weeks. As a starter project I decided to try and replicate the mobile game Pop the Lock. Right now, I'm having some problems with my keyboard inputs that I just can't figure out how to solve.
This is how my game screen looks: GameScreen. The red bar is the Player and the yellow circle is the Target. As the game progresses, the Player rotates around the ring towards the Target.
Basically, if the Player and the Target are touching AND the Player presses the Space Key at the exact same time, the Player is supposed to gain a point. The Target is also supposed to be destroyed, and a new Target is supposed to randomly be spawned in somewhere on the game screen. At the moment, this system works ... most of the time. About 80% of the time my code operates as it should, but around 20% of the time my code doesn't register when player presses the space key as the two collide. Here's my code:
public class Target: MonoBehaviour {
public GameObject target;
void Update () {
if (Input.GetKeyDown("space")) {
Debug.Log("SPACE PRESSED!!");
}
}
private void OnTriggerEnter2D (Collider2D collision) {
Debug.Log("Collision!");
}
private void OnTriggerStay2D(Collider2D other) {
// This is the part that sometimes isn't registering:
if (Input.GetKeyDown("space")) {
Debug.Log("HIT!!");
Score.score++;
// Code to spawn new Target on random place in the ring:
// Seems to be working as intended:
float distance = 2.034822f;
float x = Random.Range(-2f, 2f);
float y = Mathf.Pow(distance,2) - Mathf.Pow(x,2);
y = Mathf.Sqrt(y);
float[] options = {y, -y};
int randomIndex = Random.Range(0, 2);
y = options[randomIndex];
Vector3 vector = new Vector3(x, y, 0);
GameObject newTarget = Instantiate(target, vector, Quaternion.identity);
Destroy(gameObject);
}
}
}
As you can see I have Log statements that print something every time the player and the target are touching, every time the space key is pressed, and every time the space key is pressed while they are touching. This is how the console looks like when everything is working : Image One. This is what the console looks like when my code isn't working : Image Two.
So even when it isn't working, the collision and the key press are still registered at the exact same time. But for some reason the hit itself isn't registered (so the if condition isn't passed). Because of this I'm quite confident that it's not just input delay or me pressing the key at the wrong time. As I mentioned above, this only happens about 20% of the time, which makes it even more confusing to me. The Target has a trigger collider2D and it also has a dynamic RigidBody2D with gravity scale set to 0 (as I was told it should). Any help would be greatly appreciated.
(How my collider and rigidbody look: Image)
Something you can do is to set a flag to becomes true while you are pressing the key in the update loop, so the update loop will convert to something like:
private bool isSpacePressed = false;
update() {
isSpacePressed = false;
if (Input.GetKeyDown(KeyCode.Space)){
isSpacePressed = true;
}
}
so every loop the flag will be set to false except if you are pressing the space bar and the OnTriggerStay2D while become something like
OnTriggerStay2D () {
if(isSpacePressed){
.. do magic..
}
}
Look that I replace the Input.GetKeyDown('space') to Input.GetKeyDown(KeyCode.Space) I recommend using this one to avoid typing errors

How can I execute code if something is true, continue executing the code indefinitely, but stop evaluating the if statement?

I'm just starting out please excuse vast ignorance.
I'm writing a c# script in unity as part of the essentials training. I'm doing the 3d audio module and I thought I'd try and get a little bit fancier than the scope of this particular lesson which is supposed to be having an object fly through a window in a pre-built scene and make a 3d sound as it moves.
I wanted to make the movement of the object conditional upon a player moving close to it in 3d space. I figured out how to trigger the movement of an object in a script with an if statement that changes the transform parameters of the object the script is attached to when a 'distanceFromObject' variable is < 2. It works, however the script runs in the update section of the script which runs once every frame. This means that the object's transform parameters are changed every frame as expected but of course stops doing so when the distance between the object that's moving and the player exceeds 2.
I see the mistake I've made because if the object moves away when the player gets close then it will inevitably eventually move far enough away that the distanceFromObject variable will grow bigger than 2 whereupon it stops and just hovers in place. I don't know how to fix it though.
I need the script to check the distance between the object and the player every frame so that it will trigger the instance the player gets close enough, and when they get close enough, I need the object to move away, however once it has been triggered to move, I need the object to continue moving, but the script to stop checking what the distance is anymore.
The script looks like this
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class FlyOff : MonoBehaviour
{
public Vector3 rotateChange;
public Vector3 positionChange;
public float distanceFromObject;
public GameObject character;
// Start is called before the first frame update
void Start()
{
}
// Update is called once per frame
void Update()
{
distanceFromObject = Vector3.Distance(character.transform.position, this.gameObject.transform.position);
print (distanceFromObject);
if (distanceFromObject < 2)
{
transform.Rotate (rotateChange);
transform.position += positionChange;
}
}
}
Use flags instead of writing your logic in the if statement :
public class FlyOff : MonoBehaviour
{
// fields removed for more readability
// use a flag that's set to true/false
private bool isCloseEnough = false;
void Update()
{
distanceFromObject = Vector3.Distance(character.transform.position, this.gameObject.transform.position);
print (distanceFromObject);
// set the flag to true when player is close enough
if (distanceFromObject < 2)
{
isCloseEnough = true;
}
// even if the player gets far, the flag will remain true
if (isCloseEnough)
{
transform.Rotate (rotateChange);
transform.position += positionChange;
}
}
}
You can even apply the opposite logic to stop the object to move away when it has reach a certain distance :
if (distanceFromObject < 2)
{
isCloseEnough = true;
}
else if (distanceFromObject > SomeValue)
{
isCloseEnough = false;
}
If I understand correctly you could just add a bool flag and set it once you are close enough. Then you can start moving and skip further distance checks but keep moving forever.
private bool flyAway;
void Update()
{
if(!flyAway)
{
distanceFromObject = Vector3.Distance(character.transform.position, transform.position);
print (distanceFromObject);
if (distanceFromObject < 2)
{
flyAway = true;
}
}
else
{
transform.Rotate (rotateChange);
transform.position += positionChange;
}
}
In general: Avoid using print every frame! Even if you user doesn't see the log in a built app it is still causing overhead!

Letting The Character Traverse Between Art Canvases When There Are Intersecting Sides in Unity2D

I am creating a video game where the character has to travel within literal art canvases (the ones that you use for painting) to reach the end goal.
Note that the "canvas" I am referring is not the UI element, but the actual canvases you would see in real life.
I based my code off the concepts of portals. This may not be the most efficient way of dealing with it and I will consider all advices.
This is my current code:
public Transform PortalB;
public CharacterController2D Player;
public GameObject PlayerObject;
private GameObject CloneTemporary;
public Queue<GameObject> Clones = new Queue<GameObject>();
private bool isCreated = false;
// Use this for initialization
void Start () {
Clones.Enqueue(PlayerObject);
}
// Update is called once per frame
void Update () {
// Portal adapts to the player's current position
if (Player == null) {
Player = GameObject.FindWithTag("Player").GetComponent<CharacterController2D>();
PlayerObject = GameObject.FindWithTag("Player");
}
}
void OnTriggerEnter2D (Collider2D other) {
if (other.gameObject.tag == "Player") {
if (Vector2.Distance(transform.position, other.transform.position) > 0.7f) {
if (!isCreated) {
CloneTemporary = Instantiate(PlayerObject, new Vector2 (PortalB.position.x, PortalB.position.y), Quaternion.identity) as GameObject;
Clones.Enqueue(CloneTemporary);
isCreated = true;
}
}
}
}
void OnTriggerExit2D (Collider2D other) {
if (Vector2.Distance(transform.position, other.transform.position) > 0.7f) {
print(Clones.Count);
if (Clones.Count > 1) {
UnityEngine.Object.Destroy(Clones.Dequeue());
}
}
isCreated = false;
}
The "original character" will collide with the portal's box collider and create a copy on the other end of the portal. The box collider is annotated in red in the first image below. Note that the sizes are exactly the same.
Note that it technically is not a portal, but since it's a box which brings a character from one place to another, I might as well call it a portal.
Once the original leaves the box collider, it will get deleted, and the clone will then become the "original".
I am using a queue system to determine which "clone" gets deleted first.
There are a few problems with this:
It is very inefficient. I have to create portals manually for every intersection point in the canvases. Imagine a level full of canvases, and imagine a game with full of levels...
When it touches the portal, a duplicate will get spawned by the original character. There are three characters, but the Clones.Count only registers two.
I am not sure how well the code will work for vertical traverses.
When the character crosses the portal, it should be able to turn back. In this code, the character would glitch through the floor if he were to turn back and not get deleted by the OnExit function. I suspect this has something to do with the size of the portal, but I can foresee that even if it were to be bigger, the character would immediately disappear if he turns back.
I think the OnTriggerEnter function gets activated when the character is teleported on the other side. This might have an effect on the errors I just stated, but it may cause more in the near future.

Moving Platform works most of the time, but occasionally falls through and/or is jittery

I'm writing a 2D game and I'm trying to get moving platforms to work. After doing some previous investigation, I have it ALMOST working. The idea is to have 2 platform objects with colliders: 1 a visible object, the other an invisible object with isTrigger set (since the player would just go through a trigger). The code for the Moving Platform child (the trigger one) is set here.
using UnityEngine;
using System.Collections;
public class MovingPlatformChild : MonoBehaviour
{
public string parentPlatform = "";
void Start ()
{
transform.parent = GameObject.Find(parentPlatform).transform;
}
// Update is called once per frame
void Update ()
{
}
void OnTriggerEnter(Collider playerObject)
{
Debug.Log ("enter moving platform");
if(playerObject.gameObject.name.Contains("Player"))
{
playerObject.transform.parent = gameObject.transform;
}
}
int i = 0;
void OnTriggerStay(Collider playerObject)
{
Debug.Log ("stay" + i++);
if(playerObject.transform.position.y >= transform.position.y)
{
playerObject.transform.parent = gameObject.transform;
}
else
{
playerObject.transform.parent=null;
}
}
void OnTriggerExit(Collider playerObject)
{
Debug.Log ("EXIT");
if(playerObject.gameObject.name.Contains("Player"))
{
playerObject.transform.parent=null;
}
}
}
The Start() function just makes it a child of the visible platform. This can probably be done right in the Unity editor as well, instead of through code.
The OnTriggerEnter function adds the player object as a child of the trigger platform object, which is a child of the visible platform. So they should all move together.
The OnTriggerStay is an attempt to verify that this remains true only while the player is on the top of the platform. While the player is within the trigger, if the player is on top of the platform, then it remains attached. Otherwise, it's not. This is so that nothing happens on the bottom end.
The OnTriggerExit function just removes the player object as a child when it exits the trigger.
This is somewhat working (but we know somewhat isn't good enough). It works sometimes, but the player will be very jittery. Also, on the way down while standing atop the platform, the TriggerStay function doesn't appear to be called (implying the player is no longer within the trigger). This is observed through my Debug "stay" statement. Finally, sometimes the player will also fall straight through the platform.
What in this code would allow the player to fall through the platform, or be so jittery on the way up? Am I missing something crucial? If you need any more code, please let me know.
Below is the code for the movement of the non-trigger platform (the parent of the trigger platform and in an identical position). I will also share the Player's Update function after that.
void Start ()
{
origY = transform.position.y;
useSpeed = -directionSpeed;
}
// Update is called once per frame
void Update ()
{
if(origY - transform.position.y > distance)
{
useSpeed = directionSpeed; //flip direction
}
else if(origY - transform.position.y < -distance)
{
useSpeed = -directionSpeed; //flip direction
}
transform.Translate(0,useSpeed*Time.deltaTime,0);
}
And now the player code:
void Update()
{
CharacterController controller = GetComponent<CharacterController>();
float rotation = Input.GetAxis("Horizontal");
if(controller.isGrounded)
{
moveDirection.Set(rotation, 0, 0); //moveDirection = new Vector3(rotation, 0, 0);
moveDirection = transform.TransformDirection(moveDirection);
//running code
if(Input.GetKey(KeyCode.LeftShift) || Input.GetKey(KeyCode.RightShift)) //check if shift is held
{ running = true; }
else
{ running = false; }
moveDirection *= running ? runningSpeed : walkingSpeed; //set speed
//jump code
if(Input.GetButtonDown("Jump"))
{
//moveDirection.y = jumpHeight;
jump ();
}
}
moveDirection.y -= gravity * Time.deltaTime;
controller.Move(moveDirection * Time.deltaTime);
}
EDIT: I've added the specifications for the platforms and player in this imgur album:
http://imgur.com/a/IxgyS
This largely depends on the height of your trigger box, but it's worth looking into. Within your TriggerStay, you've got an IF statement concerning the player y coordinates. If the trigger box is fairly large and the platform's speed fast enough, on the way up and between update ticks the player Y coords could momentarily be smaller than the trigger Y coords. This would lead to him losing the parentage, only to regain it a few ticks later. This might be the cause of the 'jittering'.
The problem I was having included
The moving platform was written using Translate. I rewrote it using a rigidbody and the rigidbody.Move function. This didn't immediately help, but...
I realized the CharacterMotor script (Unity provides this) that I had attached to the player included moving platform support. I set the MovementTransfer value to PermaLocked, and also unchecked the "Use FixedUpdate" box on the script, and it now works 99% of the time. I've had one time where I did a particular behaviour and slipped through, but I can't recreate it.
Hope this helps anyone who might be looking for an answer!

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