Develop Reference

Teleport while Controlling GameObject in Unity3D

I am a freshman design student and they've asked us to create a game on unity3D without much training on it so needless to say I don't know much except for the super basic stuff. I don't know anything about c# and I've been having an issue making a gameobject teleport. I've spent 6 hours searching for a solution online and the only conclusion I got to was that my object is probably having issues teleporting because of the way I am controlling it - something to do with the controller remembering the last position before the teleport and returning to it. I have no idea how to fix it though.
So this is what my scene looks like: I have a sphere as my character, I move it to this other object that has a collider as trigger which then teleports my sphere to a different point (black object) on the terrain. As soon as my object reaches there, it starts sliding back to the point where the teleport happened. I even tried edit > project settings > physics > auto sync transforms as many suggested that and it worked for them.
This is the code by which I control my player:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class MyPlayer : MonoBehaviour
{
public float speed = 1;
public float spacing = 1;
private Vector3 pos;
// Use this for initialization
void Awake()
{
pos = transform.position;
}
// Update is called once per frame
void Update()
{
if (Input.GetKeyDown(KeyCode.W))
pos.x += spacing;
if (Input.GetKeyDown(KeyCode.S))
pos.x -= spacing;
if (Input.GetKeyDown(KeyCode.D))
pos.z -= spacing;
if (Input.GetKeyDown(KeyCode.A))
pos.z += spacing;
transform.position = Vector3.MoveTowards(transform.position, pos, speed * Time.deltaTime);
}
}
and I also have a camera that follows the sphere using this code
using UnityEngine;
using System.Collections;
public class CompleteCameraController : MonoBehaviour {
public GameObject player; //Public variable to store a reference to the player game object
private Vector3 offset; //Private variable to store the offset distance between the player and camera
// Use this for initialization
void Start ()
{
//Calculate and store the offset value by getting the distance between the player's position and camera's position.
offset = transform.position - player.transform.position;
}
// LateUpdate is called after Update each frame
void LateUpdate ()
{
// Set the position of the camera's transform to be the same as the player's, but offset by the calculated offset distance.
transform.position = player.transform.position + offset;
}
}
and I have another code on the camera that makes me be able to look around using my mouse
using UnityEngine;
using System.Collections;
public class FlyCamera : MonoBehaviour
{
/*
Writen by Windexglow 11-13-10. Use it, edit it, steal it I don't care.
Converted to C# 27-02-13 - no credit wanted.
Simple flycam I made, since I couldn't find any others made public.
Made simple to use (drag and drop, done) for regular keyboard layout
wasd : basic movement
shift : Makes camera accelerate
space : Moves camera on X and Z axis only. So camera doesn't gain any height*/
float mainSpeed = 700.0f; //regular speed
float shiftAdd = 950.0f; //multiplied by how long shift is held. Basically running
float maxShift = 2000.0f; //Maximum speed when holdin gshift
float camSens = 0.25f; //How sensitive it with mouse
private Vector3 lastMouse = new Vector3(255, 255, 255); //kind of in the middle of the screen, rather than at the top (play)
private float totalRun = 1.0f;
void Update()
{
lastMouse = Input.mousePosition - lastMouse;
lastMouse = new Vector3(-lastMouse.y * camSens, lastMouse.x * camSens, 0);
lastMouse = new Vector3(transform.eulerAngles.x + lastMouse.x, transform.eulerAngles.y + lastMouse.y, 0);
transform.eulerAngles = lastMouse;
lastMouse = Input.mousePosition;
//Mouse camera angle done.
//Keyboard commands
float f = 0.0f;
Vector3 p = GetBaseInput();
if (Input.GetKey(KeyCode.LeftShift))
{
totalRun += Time.deltaTime;
p = p * totalRun * shiftAdd;
p.x = Mathf.Clamp(p.x, -maxShift, maxShift);
p.y = Mathf.Clamp(p.y, -maxShift, maxShift);
p.z = Mathf.Clamp(p.z, -maxShift, maxShift);
}
else
{
totalRun = Mathf.Clamp(totalRun * 0.5f, 1f, 1000f);
p = p * mainSpeed;
}
p = p * Time.deltaTime;
Vector3 newPosition = transform.position;
if (Input.GetKey(KeyCode.Space))
{ //If player wants to move on X and Z axis only
transform.Translate(p);
newPosition.x = transform.position.x;
newPosition.z = transform.position.z;
transform.position = newPosition;
}
else
{
transform.Translate(p);
}
}
private Vector3 GetBaseInput()
{ //returns the basic values, if it's 0 than it's not active.
Vector3 p_Velocity = new Vector3();
if (Input.GetKey(KeyCode.W))
{
p_Velocity += new Vector3(0, 0, 1);
}
if (Input.GetKey(KeyCode.S))
{
p_Velocity += new Vector3(0, 0, -1);
}
if (Input.GetKey(KeyCode.A))
{
p_Velocity += new Vector3(-1, 0, 0);
}
if (Input.GetKey(KeyCode.D))
{
p_Velocity += new Vector3(1, 0, 0);
}
return p_Velocity;
}
}
Please let me know if there's a specific part of my code that I need to edit to resolve this or alternatively if you have a different code that won't give me this issue, that would make my life so much easier. If I need to edit something or you're sharing a code, please respond with the complete (corrected) code because otherwise I will just be even more confused.
I know this is a super long post and I am sorry but I am really desperate. It's been really hard studying online and basically having to teach myself all of this. This is for a final project so I will really appreciate any help you can throw my way. Thank you for reading and thanks for any help in advance.
EDIT: The teleport code is executing fine because I do teleport to the chosen location, I just end up sliding back to the point which I teleported from.
This is the teleporting code I am using.
using UnityEngine;
using System.Collections;
public class Teleport : MonoBehaviour
{
public GameObject ui;
public GameObject objToTP;
public Transform tpLoc;
void Start()
{
ui.SetActive(false);
}
void OnTriggerStay(Collider other)
{
ui.SetActive(true);
if ((other.gameObject.tag == "Player") && Input.GetKeyDown(KeyCode.E))
{
objToTP.transform.position = tpLoc.transform.position;
}
}
void OnTriggerExit()
{
ui.SetActive(false);
}
}

Ok, so the main reason why your character is drifting back to original position is that the pos variable in the MyPlayer script stays the same after teleporting.
Remedy for that will be changing pos variable from Teleport script after objToTP.transform.position = tpLoc.transform.position;. Something like objToTP.gameobject.GetComponent<MyPlayer>().pos = tpLoc.transform.position;
But make sure that objToTP has component MyPlayer and pos in MyPlayer is public.
Once again: it's a simple way to resolve your problem. In a real project you should create more flexible architecture, but that's a different story.

I believe that you sliding back because you moving player with transform.position = Vector3.MoveTowards in Update().
And you moving it to coordinates that was got from your input

How to make a thrown object rotate automatically based on the direction its thrown in?

so what I am trying to do is pull a spear back(like a slingshot) and send it flying, all the while making it rotate while it's flying in the air to mimic a real thrown spear. So far, I have only been able to make it rotate after a few seconds to a certain position but I can already tell that this isn't really a permanent fix and will definitely lead to problems down the line. I have tried looking for better ways of rotating the object but I can't really find anybody else who had a problem like this and it's hard to understand the unity documentation regarding rotation as it's for 3D objects.
Here is a gif showing how it looks like:
https://gfycat.com/chiefglasshorsemouse
This is the code that I have attached to my spear object that's responsible for letting me pull it back and launch it with the mouse:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.SceneManagement;
using UnityEngine.Scripting.APIUpdating;
public class spear : MonoBehaviour
{
Rigidbody2D rb;
Vector3 velocity;
private Vector3 _initialPosition;
[SerializeField] private float _launchPower = 500;
bool rotating = false;
public GameObject objectToRotate;
private float _timeSittingAround;
private bool _spearWasLaunched;
[SerializeField] private float _spearRotation = 360;
private void Awake()
{
_initialPosition = transform.position;
rb = GetComponent<Rigidbody2D>();
}
void Start()
{
rb = GetComponent<Rigidbody2D>();
}
//rotates the spear
IEnumerator rotateObject(GameObject gameObjectToMove, Quaternion newRot, float duration)
{
if(rotating)
{
yield break;
}
rotating = true;
Quaternion currentRot = gameObjectToMove.transform.rotation;
float counter = 0;
while(counter < duration)
{
counter += Time.deltaTime;
gameObjectToMove.transform.rotation = Quaternion.Lerp(currentRot, newRot, counter / duration);
yield return null;
}
rotating = false;
}
//reloads the scene if spear goes out of bounds or lays dormant for 2 seconds
void Update()
{
GetComponent<LineRenderer>().SetPosition(0, transform.position);
GetComponent<LineRenderer>().SetPosition(1, _initialPosition);
if (_spearWasLaunched &&
GetComponent<Rigidbody2D>().velocity.magnitude <= 0.1)
{
_timeSittingAround += Time.deltaTime;
}
if(transform.position.y > 30 ||
transform.position.y < -12.5 ||
transform.position.x > 40 ||
transform.position.x < -20 ||
_timeSittingAround > 2)
{
string currentSceneName = SceneManager.GetActiveScene().name;
SceneManager.LoadScene(currentSceneName);
}
}
//slingshot mechanic
private void OnMouseDrag()
{
Vector3 newPosition = Camera.main.ScreenToWorldPoint(Input.mousePosition);
transform.position = new Vector3(newPosition.x, newPosition.y);
}
private void OnMouseDown()
{
GetComponent<SpriteRenderer>().color = Color.red;
GetComponent<LineRenderer>().enabled = true;
}
//launches the spear when mouse is released as well as begins the rotating mechanic
private void OnMouseUp()
{
Vector2 directionToInitialPosition = _initialPosition - transform.position;
GetComponent<Rigidbody2D>().AddForce(directionToInitialPosition * _launchPower);
GetComponent<Rigidbody2D>().gravityScale = 1;
_spearWasLaunched = true;
GetComponent<LineRenderer>().enabled = false;
Quaternion rotation2 = Quaternion.Euler(new Vector3(0, 0, _spearRotation));
StartCoroutine(rotateObject(objectToRotate, rotation2, 3f));
}
}

There are a few ways to do it. You could try setting up rigidbodies and maybe joints and weighting different parts so that the tip of the spear naturally rotates the spear. More info on that here: https://answers.unity.com/questions/14899/realistic-rotation-of-flying-arrow.html
There's also another solution in that link for doing it with one line of code, making it rotate in the direction of movement.
In the top of your class, add this:
public Rigidbody2D mySpear;
Then in the inspector, drag the spear object into that slot to assign it. Then in your code, remove all your rotation code. In Update() add this:
mySpear.transform.right =
Vector2.Slerp(mySpear.transform.right, mySpear.rigidbody.velocity.normalized, Time.deltaTime)
A third way to do it is...
Figure out the rotation (on the z axis) of the object when it's pointing directly down. Put that down as a constant called downRotation or something.
Set a minimum velocity and maximum velocity that will be used by the rotation.
I recommend also adding an AnimationCurve variable.
Instead of having a special function for rotation, just put it in FixedUpdate. If the spear's velocity.x is not 0, then rotate.
The speed of the rotation should be based on the speed of the object. If the object's x velocity is very slow then it would probably fall (rotate) more quickly. If it's going very fast, the rotation would not change much.
Don't use this exact code, but it'd look something like this:
// This part figures out how fast rotation should be based on how fast the object is moving
var curve = speedCurve.Evaluate(1 - ((rigidBody.velocity.x - minVelocity) / (maxVelocity - minVelocity)));
// Rotates the spear
var rotate = rigidBody.rotation.eulerAngles;
var speed = curve * rotateSpeed * Time.fixedDeltaTime;
rotate.z = Mathf.MoveTowards(rotate.z, downRotation, speed);
transform.rotation = Quaternion.Euler(rotate);
Side note: You should use rigidbody rotation like I am here, and you should be assigning components to variables in the inspector instead of calling GetComponent every frame.

How to rotate camera around player in unity c#

I need to rotate the camera around my player gameobject while holding the left mouse button. How would I approach this?
Also, I've read a bit on Vector 3, but I don't have a full understanding of it. Anybody who could explain it would be greatly appreciated.
I've looked at youtube videos and this one is exactly the concept I was looking for. I was just having trouble applying it to my code.
I'm on a bit of a time crunch, exams are nearing and my teacher hasn't explained most things that are explained in the video.
// This is my code inside the camera which follows the ball/player
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class ScriptBallCam : MonoBehaviour
{
public GameObject player;
private Vector3 offset;
void Start()
{
offset = transform.position - player.transform.position;
}
void LateUpdate()
{
transform.position = player.transform.position + offset;
}
//End of code inside camera
//Code inside of player/ball
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class ScriptBall : MonoBehaviour
{
public float speed;
private Rigidbody rb;
void Start()
{
rb = GetComponent<Rigidbody>();
}
void FixedUpdate()
{
float moveHorizontal = Input.GetAxis("Horizontal");
float moveVertical = Input.GetAxis("Vertical");
Vector3 movement = new Vector3(moveHorizontal, 0.0f, moveVertical);
rb.AddForce(movement * speed);
}
// end code
Results I'm expecting are exactly shown at 1:22 in
https://www.youtube.com/watch?v=xcn7hz7J7sI

Try this. The script goes on your camera.
Basically this script works by first getting the direction your mouse has moved in. In this case the X axis Mouse X (left/right direction). Then we take our rotation speed turnSpeed, and use it to rotate around the player by that amount of degrees using Quaternion.AngleAxis. Finally we make sure that the camera is always looking at the player by using transform.LookAt
using UnityEngine;
using System.Collections;
public class OrbitPlayer : MonoBehaviour {
public float turnSpeed = 5.0f;
public GameObject player;
private Transform playerTransform;
private Vector3 offset;
private float yOffset = 10.0f;
private float zOffset = 10.0f;
void Start () {
playerTransform = player.transform;
offset = new Vector3(playerTransform.position.x, playerTransform.position.y + yOffset, playerTransform.position.z + zOffset);
}
void FixedUpdate()
{
offset = Quaternion.AngleAxis (Input.GetAxis("Mouse X") * turnSpeed, Vector3.up) * offset;
transform.position = playerTransform.position + offset;
transform.LookAt(playerTransform.position);
}
}
There is a lot of information on this topic over here:
https://answers.unity.com/questions/600577/camera-rotation-around-player-while-following.html

How to instantiate objects for the length of an audio clip

My overall goal is to have a script that constantly generates an object along the y axis until a piece of audio stops playing. The object in question are "starfields" which are groups of stars to create the effect of outer-space. This can be done easily and I already know how to do this using a constant velocity. The hardest part for me is to generate these objects with an object that gets faster and faster.
To elaborate on this, there is a rocket that goes faster and faster using the scripts below, it multiplies a constant speed which I set (10) with the movement from a Vector3. It has an acceleration of 0.25 as you can see in the code. The idea is that the rocket keeps on flying until the audio ends and the stars stop spawning and the game ends. The rocket gradually gets faster and faster so I can't just hard-code it in.
Below is my code for the rocket and the star spawn script.
This is just one way around the problem, I have spent quite a while trying different things but nothing seems to work. I have a feeling there's an easier way around this problem.
Star spawn code:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class StarSpawn : MonoBehaviour {
// Use this for initialization
public Transform Object;
AudioSource Music;
float MusicClipLength;
float distance;
void Start()
{
Music = GetComponent<AudioSource>();
AudioClip MusicClip;
MusicClip = Music.clip;
MusicClipLength = Music.clip.length; //time
distance = ((((0.5f * 0.25f) * (MusicClipLength * MusicClipLength)))); //distance
float RoundedDistance = (float)Mathf.Floor(distance); //rounding
for (int i = 0; i <= RoundedDistance; i++) //generation loop
{
Instantiate(Object, new Vector3(0, i * 1750.0f, 500),
Quaternion.Euler(-90, 0, 90));
}
}
}
Rocket code (some of this is irrelevant)
using UnityEngine;
using System.Collections;
using UnityStandardAssets.CrossPlatformInput;
public class PlayerController : MonoBehaviour
{
public bool Launch = false;
private Rigidbody rb;
public int Speed;
void Start()
{
rb = GetComponent<Rigidbody>();
}
public void LaunchStart()
{
Launch = true;
}
void FixedUpdate()
{
float altitude = (rb.position.y);
if (Launch == true)
{
float moveHorizontal = CrossPlatformInputManager.GetAxis("Horizontal");
Vector3 movement = new Vector3(moveHorizontal, 0.25f, 0.0f);
if (altitude > 0)
{
rb.AddForce(movement * Speed);
}
}
}
}
0.25 is the acceleration for everything and 10 is the set public speed for instance.
I realise this is quite a big problem is solve so even if someone recognises an easier way around the problem I would much appreciate any advice.
Edit
My actual problem is that the stars over spawn, way too much. So when the audio has finished, there are still lots of stars left.

Using coroutines would probably be a good choice here. With that, you could then use the speed of the rocket to determine the time delay between spawning stars:
float totaltime;
void Start()
{
Music = GetComponent<AudioSource>();
AudioClip MusicClip;
MusicClip = Music.clip;
MusicClipLength = Music.clip.length; //time
distance = ((((0.5f * 0.25f) * (MusicClipLength * MusicClipLength)))); //distance
float RoundedDistance = (float)Mathf.Floor(distance); //rounding
StartCoroutine(Spawner());
}
void IEnumerator Spawner()
{
totaltime += Time.deltaTime;
while (totaltime < MusicClipLength)
{
Instantiate(Object, new Vector3(0, i * 1750.0f, 500), Quaternion.Euler(-90, 0, 90));
yield return new WaitForSeconds(rocketspeedFactor); // you should mess around with this value to get the spawning frequency correct.
// would be good to retrieve the speed from the rocket and multiple by some factor
}
}

Collision detection script fails sometimes

For the most part this script works, however every now and then an enemy will fail at pathfinding and go through a building or wall. Is there a way i can stop this?
using UnityEngine;
using System.Collections;
namespace Daniel {
public class EnemyAI : Living {
// Detection private int range = 10; private float speed = 10f; private bool isThereAnyThing = false;
// Waypoints/Targets
public GameObject[] targets;
private float rotationSpeed = 900f;
private RaycastHit hit;
GameObject target;
[SerializeField]
private int randomTarget = 0;
[SerializeField]
float timeToNextCheck = 3;
public float effectTimer = 2f;
public GameObject deathEffect;
public LayerMask detectThis;
void Start()
{
randomTarget = Random.Range(0, 8);
target = targets[randomTarget];
}
void FixedUpdate()
{
timeToNextCheck = timeToNextCheck - Time.deltaTime;
ScanForNewWaypoint();
LookAtTarget();
Move();
CheckForObsticales();
}
void LookAtTarget()
{
//Look At Somthly Towards the Target if there is nothing in front.
if (!isThereAnyThing)
{
Vector3 relativePos = target.transform.position - transform.position;
Quaternion rotation = Quaternion.LookRotation(relativePos);
transform.rotation = Quaternion.Slerp(transform.rotation, rotation, Time.deltaTime);
}
}
void Move()
{
// Enemy translate in forward direction.
transform.Translate(Vector3.forward * Time.deltaTime * speed);
}
public void CheckForObsticales()
{
//Checking for any Obstacle in front.
// Two rays left and right to the object to detect the obstacle.
Transform leftRay = transform;
Transform rightRay = transform;
//Use Phyics.RayCast to detect the obstacle
if (Physics.Raycast(leftRay.position + (transform.right * 7f), transform.forward, out hit, range, detectThis) || Physics.Raycast(rightRay.position - (transform.right * 7f), transform.forward, out hit, range))
{
if (hit.collider.gameObject.CompareTag("Obstacles"))
{
isThereAnyThing = true;
transform.Rotate(Vector3.up * Time.deltaTime * rotationSpeed);
}
}
// Now Two More RayCast At The End of Object to detect that object has already pass the obsatacle.
// Just making this boolean variable false it means there is nothing in front of object.
if (Physics.Raycast(transform.position - (transform.forward * 4), transform.right, out hit, 10, detectThis) ||
Physics.Raycast(transform.position - (transform.forward * 4), -transform.right, out hit, 10, detectThis))
{
if (hit.collider.gameObject.CompareTag("Obstacles"))
{
isThereAnyThing = false;
}
}
}
public void ScanForNewWaypoint()
{
CheckForObsticales();
if (timeToNextCheck <= 0)
{
timeToNextCheck = Random.Range(6, 3);
randomTarget = Random.Range(0, 8);
target = targets[randomTarget];
}
}
public override void TakeHit(float dmg, Vector3 hitPoint, Vector3 hitDirection)
{
if (dmg >= health)
{
Destroy(Instantiate(deathEffect, hitPoint, Quaternion.FromToRotation(Vector3.forward, hitDirection)) as GameObject, effectTimer);
Debug.Log("Exploded");
}
base.TakeHit(dmg, hitPoint, hitDirection);
}
}
}

Okay now this is one of the most common problems people face when playing with Physics Engine and believe me there are lot of factors that adds up to the result/consequences you are facing. Most common solutions devised by people is to use Update which is Executed Every Frame for Physics calculation which is Entirely Wrong. All the physics related calculation needs to be performed inside the Fixed Update otherwise it will be too expensive to execute physics based simulations in the Update which means every single frame. In your case where your Enemy is going through walls and Physics Collisions are missing the best solution you can take is to tweak some Physics Related Properties in Unity these are located in Edit>>>Project Settings>>>Time change the Time Step and Maximum Allowed Time Step in the inspector to set your collisions right. There are some other things to keep in mind too while dealing with physics like scale, mass and colliders etc. Here is a Link concerning the detailed mechanics of the physics settings in unity. Make sure you read and understand the contents of the link before working and tweaking physics settings.