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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!

Still pausing/resuming and start a new game is not working good. Can'r figure what should I do?

First a screenshot of my Hierarchy :
Everything is inside a one scene name The :
The game start when Main Game is disabled. Inside Main Game sit all the game objects. The Main Menu and Game Manager are enabled.
When running the game first time, When the game start there is short animation of the player for 5 seconds. The player start from some rotating degrees on Z. Z = 50 when x and y both are 0. Then the player is rotating slowly over the Z to 0.
It's like the player is sleeping and awake up.
I'm using post processing stack by unity.
And here is the first problem. While the player is rotating on the Z and post processing effect is working if I press the Escape key it will bring me back to the Main Menu but then if I press the Escape key again it will start the game over again from the begin.
But if I'm waiting in my game for the player to finish rotating on the Z and the post processing effect is finished and then pressing on Escape it will bring the main menu and second time will resume the game from the same point.
I can't figure out why when the player is rotating and the post process is working the escape key make it start the game over again from the being ?
This is a screenshot of the game when start and after finish the rotating and the process stack :
Another problem I noticed now. After the game start using the post process and the player rotating finished if I press Escape it will go to main menu and escape again will be back to the game but for example in the second screenshot the conversation is not continue. It will return to the same point in the game but things not seems to continue like the conversation.
On the Back to main menu object I have a script attached to it :
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.SceneManagement;
public class BackToMainMenu : MonoBehaviour
{
private bool _isInMainMenu = false;
public GameObject mainGame;
public GameObject mainMenu;
void Update()
{
if (Input.GetKeyDown(KeyCode.Escape))
{
if (!_isInMainMenu)
{
// -- Code to freeze the game
mainGame.SetActive(false);
mainMenu.SetActive(true);
}
else
{
// -- Code to unfreeze the game
mainGame.SetActive(true);
mainMenu.SetActive(false);
}
_isInMainMenu = !_isInMainMenu;
}
}
}
On the Main Menu object under Main Menu I have attached this script :
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.SceneManagement;
public class MainMenu : MonoBehaviour
{
public GameObject mainGame;
public GameObject mainMenu;
public void PlayGame()
{
mainGame.SetActive(true);
mainMenu.SetActive(false);
}
public void QuitGame()
{
Application.Quit();
}
}
On the PLAY button I'm using this script method PlayGame from the MainMenu script.
In the Main Game object on the Player object attached to thew Player I have some scripts the controller :
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class PlayerController : MonoBehaviour
{
public float speed = 10.0f;
// Update is called once per frame
void Update()
{
float translatioin = Input.GetAxis("Vertical") * speed;
float straffe = Input.GetAxis("Horizontal") * speed;
translatioin *= Time.deltaTime;
straffe *= Time.deltaTime;
transform.Translate(straffe, 0, translatioin);
}
}
Player Lock Manager :
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class PlayerLockManager : MonoBehaviour
{
public PlayerCameraMouseLook playerCameraMouseLook;
public PlayerController playerController;
// Start is called before the first frame update
public void PlayerLockState(bool LockPlayer, bool LockPlayerCamera)
{
if (LockPlayer == true)
{
playerController.enabled = false;
}
else
{
playerController.enabled = true;
}
if (LockPlayerCamera == true)
{
playerCameraMouseLook.enabled = false;
}
else
{
playerCameraMouseLook.enabled = true;
}
}
}
And Mouse Lock State :
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class MouseLockState : MonoBehaviour
{
public bool lockState = true;
private void Start()
{
LockState(lockState);
}
private void Update()
{
}
public void LockState(bool lockState)
{
if (lockState == false)
{
Cursor.visible = true;
Cursor.lockState = CursorLockMode.None;
}
else
{
Cursor.visible = false;
Cursor.lockState = CursorLockMode.Locked;
}
}
}
Under the Player as child I have the Player Camera object and attached to the Player Camera also some scripts :
Player Camera Mouse Look :
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class PlayerCameraMouseLook : MonoBehaviour
{
public float sensitivity = 5.0f;
public float smoothing = 2.0f;
private GameObject player;
private Vector2 mouseLook;
private Vector2 smoothV;
// Use this for initialization
void Start()
{
player = this.transform.parent.gameObject;
}
// Update is called once per frame
void Update()
{
var md = new Vector2(Input.GetAxisRaw("Mouse X"), Input.GetAxisRaw("Mouse Y"));
md = Vector2.Scale(md, new Vector2(sensitivity * smoothing, sensitivity * smoothing));
smoothV.x = Mathf.Lerp(smoothV.x, md.x, 1f / smoothing);
smoothV.y = Mathf.Lerp(smoothV.y, md.y, 1f / smoothing);
mouseLook += smoothV;
mouseLook.y = Mathf.Clamp(mouseLook.y, -90f, 90f);
transform.localRotation = Quaternion.AngleAxis(-mouseLook.y, Vector3.right);
player.transform.localRotation = Quaternion.AngleAxis(mouseLook.x, Vector3.up);
}
}
And Depth Of Field script :
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.PostProcessing;
public class DepthOfField : MonoBehaviour
{
public GameObject player;
public PostProcessingProfile postProcessingProfile;
public bool dephOfFieldFinished = false;
public PlayerLockManager playerLockManager;
private Animator playerAnimator;
private float clipLength;
// Start is called before the first frame update
void Start()
{
playerAnimator = player.GetComponent<Animator>();
AnimationClip[] clips = playerAnimator.runtimeAnimatorController.animationClips;
foreach (AnimationClip clip in clips)
{
clipLength = clip.length;
}
var depthOfField = postProcessingProfile.depthOfField.settings;
depthOfField.focalLength = 300;
StartCoroutine(changeValueOverTime(depthOfField.focalLength, 1, clipLength));
postProcessingProfile.depthOfField.settings = depthOfField;
}
IEnumerator changeValueOverTime(float fromVal, float toVal, float duration)
{
playerLockManager.PlayerLockState(true, true);
float counter = 0f;
while (counter < duration)
{
var dof = postProcessingProfile.depthOfField.settings;
if (Time.timeScale == 0)
counter += Time.unscaledDeltaTime;
else
counter += Time.deltaTime;
float val = Mathf.Lerp(fromVal, toVal, counter / duration);
dof.focalLength = val;
postProcessingProfile.depthOfField.settings = dof;
yield return null;
}
playerAnimator.enabled = false;
dephOfFieldFinished = true;
}
}
I have under Main Game also a object name Openning Scene and attached to it :
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class OpeningCutscene : MonoBehaviour
{
public NaviConversations naviConversation;
public DepthOfField dephOfField;
// Update is called once per frame
void Update()
{
if (dephOfField.dephOfFieldFinished == true)
{
naviConversation.PlayNaviConversation(0);
dephOfField.dephOfFieldFinished = false;
}
}
}
It's a bit long but everything is connected.
The game start with the main menu.
When clicking the PLAY button a new game start.
When a new game start the script Depth Of Field is in action using the post processing. Also I'm locking the player so the player will not be able to move either the mouse or the player it self.
When the depth of field script finished his work a conversation between Navi and the Player start. When a conversation is in action the player can move the mouse 360 degrees but cant move the player to any direction.
When the conversation ended the player can also move to any direction.
Problems :
When start a new game while the depth of field script is in work pressing escape will bring the main menu but pressing escape again will not resume the depth of field script but will start it all over again.
When waiting the conversation to end if not pressing escape until the conversation ended then when moving around and pressing escape it will bring the main menu and again will resume the game from the same point.
The problems is when the game is doing something like the depth of field it will start the game over again instead resuming or when in conversation in the middle the conversation will never continue.
The ides with the escape key is once to get to main menu and second to resume the game.
The PLAY button is what should only start a new game and not the escape key.
It's a bit long but everything is connected.

I can't see which objects you hooked up to mainGame and mainMenu in BackToMainMenu from your hierarchy, so I have some conjecture in here.
Sounds like you want Escape key to pause, and unpause, as well as bring up a menu, you want Play button in the menu to restart your game.
However, in both MainMenu and BackToMainMenu you use the same code:
mainGame.SetActive(true);
mainMenu.SetActive(false);
This just turns the objects on and off in the hierarchy. This means the first time you do one of these things, all objects turned on under the gameobject referenced by mainGame will run their Awake and Start methods, but not the second time. Also depending which objects are active (like I said I can't fully see what component is on what object and which objects are referenced by which serialized field) you might be able to introduce a state error on BackToMainMenu._isInMainMenu because that field isn't changed when you hit play. Here is a fantastic image showing execution timeline in Unity:
Monobehavior Timeline
In summary:
The second time you run the game DepthOfField won't call Start a second time. Instead try OnEnable.
The conversation and game logic is not shown in your post, but likely it also is initializing in Start and won't run a second time.
A bit of trickiness around Coroutines is likely to blame here. When DepthOfField starts it also starts a coroutine. That coroutine keeps going even if you set the gameobject inactive. So you run the game once, that coroutine starts, you turn the object off when you hit escape, the coroutine finishes, you hit play again, but DepthOfField.dephOfFieldFinished == true and your playerAnimator is disabled and won't enable again.
Also 5. This kind of behavior can be tricky and is usually dependent on what else you have going on in your scene. Since you have one scene with everything at once, you need to watch out for putting stuff in Awake and Start since this will only run once. Instead you can try a number of things, my favorite is usually to set up a singleton or static class that works as a state machine for the whole scene. It will call custom Initialize functions in your behaviors instead of using Awake and Start.
Keep references to your coroutines by doing things like:
private Coroutine depthOfFieldRoutineRef;
private OnEnable()
{
if (depthOfFieldRoutineRef != null)
{
StopCoroutine(depthOfFieldRoutineRef);
}
depthOfFieldRoutineRef =
StartCoroutine(changeValueOverTime
(depthOfField.focalLength, 1, clipLength));
// Don't forget to set depthOfFieldRoutineRef to null again at the end of routine!
}
For simple pausing behavior you can also try setting Time.timescale = 0; and back to 1 when you want play to resume.
Less a question than a set of problems, hopefully this set of solutions helps!
Tutorial on Awake and Start
Docs on Coroutines
Docs on Time.timescale

OnCollisionStay not working in 2D movement script

So, I'm still not the best at this but I'm trying to use this script for 2D movement but the jumping isn't working for some reason. It keeps saying that the OnCollisionEnter function "is declared but never used". Can someone tell me what im doing wrong? Thanks
If I remove the (Collision col) part it says that "void cannot be used in this context".
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class RonyWalking : MonoBehaviour
{
Rigidbody2D rigid;
SpriteRenderer sprite;
public bool isJumping;
public float spd = 2.0f;
// Start is called before the first frame update
void Start()
{
rigid = GetComponent<Rigidbody2D>();
sprite = GetComponent<SpriteRenderer>();
}
// Update is called once per frame
void Update()
{
if(Input.GetKey("d")){rigid.velocity = new Vector2(spd, 0);}
else if(Input.GetKey("a")){rigid.velocity = new Vector2(-spd, 0);}
if(Input.GetKeyDown("w") && isJumping == false)
{
rigid.velocity = new Vector2(0, 5);
isJumping = true;
}
void OnCollisionStay(Collision col)
{
isJumping = false;
}
}
}

When using 2D physics, you need to use the 2D lifecycle methods;
void OnCollisionStay2D(Collision2D col)
{
isJumping = false;
}
And you shouldn't put this method inside your Update method... It should be on class level:
public class RonyWalking
{
void Update()
{
// ...
}
void OnCollisionStay2D(Collision2D col)
{
// ...
}
}
Don't worry about "Is declared but never used", this may be because you don't have specific code referencing the method, but Unity will raise events that calls it, "automagically"
Another thing that I can see while reading your code, that may be unintentional behaviour for you, is that when clicking left/right, you set velocity UP to 0, and when clicking up you set LEFT/RIGHT velocity to 0; this will result in freezing the movement mid-air if you jump, then move while in air:
Click D; velocity = 2, 0
Click W; velocity = 0, 5
Character will now move upwards until another input is given
Click D; velocity = 2, 0 and the character will continue moving while in air because when moving sideways the up/down velocity is set to 0
To solve this, either set the other to existing velocity or make the inputs manipulate a Vector that you then apply at the end of the movement code:
Vector2 existingMovement = rigid.velocity;
if (Input.GetKey(KeyCode.D))
existningMovement.x = spd;
else if (Input.GetKey(KeyCode.A))
existningMovement.x = -spd;
if (Input.GeyKeyDown(KeyCode.W) && !isJumping)
{
existningMovement.y = 5f;
isJumping = true;
}
Furthermore, I think you may have some unexpected behaviour with OnCollisionStay; it will fire every frame that you're colliding with the ground, I assume. But I think it may also fire a frame or two AFTER you've jumped since the physics of your character will not INSTANTLY leave the collision, so isJumping will be set to false even after your jump, letting you jump while in the air one more time.
I would recommend that you use OnCollisionExit2D(Collision2D col) to set isJumping = true instead, or OnCollisionEnter2D(Collision2D col) and set it to isJumping = false, depending on the functionality you desire (if you want the ability to jump after walking out of a cliff)

Unity 2d game movement script issue - unable to jump

So basically, after hours of torment trying to create basic movement script for simple platformer game I succeeded, but not quite. Square character is able to move around and jump just ok, but sometimes it won't jump, usually while moving on short distances or, rarely, standing in place and trying to jump. I can't figure out how to fix that. Here is entire script:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class PlayerMovement : MonoBehaviour {
private Rigidbody2D rgdb2;
public float movementSpeed;
public float jumpHeight;
private bool isJumping = false;
// Use this for initialization
void Start ()
{
rgdb2 = GetComponent<Rigidbody2D>();
}
// Update is called once per frame
void FixedUpdate ()
{
float moveHorizontal = Input.GetAxis("Horizontal");
HandleMovement(moveHorizontal);
if (Input.GetKeyDown(KeyCode.Space) && isJumping == false)//by typing Space player jumps, cant double-jump
{
rgdb2.AddForce(new Vector2(rgdb2.velocity.x, 1 * jumpHeight), ForceMode2D.Impulse);
isJumping = true;
Debug.Log("jumped");
}
}
private void HandleMovement(float moveHorizontal)//applying player horizontal controls and customing player's speed by movementSpeed variable
{
rgdb2.velocity = new Vector2(moveHorizontal * movementSpeed, rgdb2.velocity.y);
}
private void OnCollisionEnter2D(Collision2D coll)
{
if (coll.transform.tag == "Platform") //if player is touching object with Platform tag, he can jump
{
Debug.Log("on ground bitch");
isJumping = false;
}
}
}
It may not be that important, but I want to polish this game as much as possilble, even if I don't need to, since it's basically my first game made in Unity3d with C#.

An important thing to keep in mind: Unity3D Engine's inputs are only updated during the time the engine calls Update() methods for your GameObjects.
What this means is that you should not read any type of input in the FixedUpdate() method. Methods like GetKeyDown() and other methods from the Input class which read keyboard/mouse/axis buttons/values should not be called during FixedUpdate(), as their returned values are unreliable.
Due to this, what is probably causing your jump implementation to fail is that the GetKeyDown() method you're calling in FixedUpdate() is returning inconsistent/invalid (false) results, when the user presses the jump key.
Fixing this can be quite simple. I suggest you keeping a boolean variable which keeps track of whether the jump key has been pressed, and gets its value updated during Update(). This should fix your problem.
bool jumpKeyPressed;
private void Update()
{
if (Input.GetKeyDown(KeyCode.Space))
jumpKeyPressed = true;
else if (Input.GetKeyUp(KeyCode.Space))
jumpKeyPressed = false;
}
private void FixedUpdate()
{
/* Update "moveHorizontal", call HandleMovement(...) here, as you've already done. */
if (jumpKeyPressed && isJumping == false)
{
// IMPORTANT: this prevents the "jump force" from being applied multiple times, while the user holds the Space key
jumpKeyPressed = false;
/* Remaining jumping logic goes here (AddForce, set "isJumping", etc) */
}
}

It's because your logic for jumping is inside FixedUpdate()
When you use GetKeyDown to register input make sure to use Update instead because if you press the key using FixedUpdate it may or may not run during that frame, test it with Update instead.
You already have in comments how Update works, it is called every frame but FixedUpdate according to Unity documentation: This function is called every fixed framerate frame
void Update ()
{
float moveHorizontal = Input.GetAxis("Horizontal");
HandleMovement(moveHorizontal);
if (Input.GetKeyDown(KeyCode.Space) && isJumping == false)//by typing Space player jumps, cant double-jump
{
rgdb2.AddForce(new Vector2(rgdb2.velocity.x, 1 * jumpHeight), ForceMode2D.Impulse);
isJumping = true;
Debug.Log("jumped");
}
}

How do I use animation events in Unity as conditions?

I'm trying to make a "player can't move while this animation is playing" check in my method for movement.
I have a 3x8 grid of panels I'm using for this application, with the player moving from panel to panel. I have 2 animations for this: MovingOut which plays when the player is moving away from a panel, and "MovingIn" which plays when the player is moving into a panel. So the flow I want is:
Player presses a movement key → movement is disabled → "MovingOut" plays → player's transform.position is moved to the target position → "MovingIn" plays → movement is re-enabled.
Each animation is only 4 frames. I currently have an animation event at the beginning of "MovingOut" which sets an int CanMove to 0, and another animation event at the end of "MovingIn" which sets CanMove to 1.
Here's what my code looks like so far:
public void Move(int CanMove)
{
//this lets me use panelManager to access methods in the PanelManager script.
panelManager = GameObject.FindObjectOfType(typeof(PanelManager)) as PanelManager;
animator = GetComponent<Animator>();
if (Input.GetAxisRaw("Horizontal") == 1 && CanMove == 1) //go right
{
movingToPanel += 1;
if (IsValidPanel(movingToPanel))
{
//play animation MovingOut
animator.Play("MovingOut");
transform.position = panelManager.GetPanelPos(onPanel + 1);
onPanel += 1;
}
else
{
movingToPanel -= 1;
}
}
//else if( ...the rest of the inputs for up/down/left are below.
}
I have MovingIn set up in the animator so that it plays at the end of the MovingOut animation, which is why I don't call it in the script:
I can't for the life of me figure out how to get CanMove passed into the method without being forced to define it upon calling the method. Currently I have Move(1); being called in my Update() method just to check if movement is working (other than this issue I'm having) and it works in the sense that I can move panel to panel, but since CanMove is being defined as 1 in the Update Function, the animation's events don't prevent the movement.
Any insight would be greatly appreciated!

You should change your design slightly. Remove canMove as a parameter being passed to Move and make it a field of the player's class. Then have one function to set canMove. Then have a separate function that allows you to move if canMove is true. Something like this:
private bool canMove = true;
public void SetMove(int setCanMove) // called with animation events
{
canMove = setCanMove == 1 ? true : false;
}
public void Move()
{
if (Input.GetAxisRaw("Horizontal") == 1 && canMove == true) //go right
{
//movement code and animation call...
}
// Other directions...
}
Then you can call the setMove funciton using your animation events and stop the player moving for the duration of them. i.e call setMove(false) at the start of the MovingOut animation and setMove(true) at the end of the MovingIn animation. This will stop canMove being set in your Update loop.

you can get the integer value from animator's GetInteger function which will return the integer value set to current animation.
if(this.GetComponent<Animator>().GetInteger(canmove)==0)
//move
else
//can't move