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Unity Simple Character Controller Script not working as expected

Im scratching my head over this one, really cant figure it out.
Im trying to implement the player movement from this example:
https://www.youtube.com/watch?v=LNidsMesxSE
Starts at minute 4:25 and ends at minute 5:20
This script tries translating all that to unity.So I started all the way over from scratch and just want to make a simple movement script.
You can plug this into any Unity version, throw the script onto and object with a CharacterController component, add a child object with a mesh that will tilt, the main object will rotate around its Y axis and move.
I do recommend using a simple T pose character or atleast a long capsule so you can better see what is happening than when you would be using a cube to test this.
The weird glitches im having is that the object randomly spasms out even though im always only adding extremely small rotations and movements every frame. And 95% of the time it doesnt happen, so I havent been able to pinpoint exactly what is causing this.
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class CharacterMove : MonoBehaviour
{
public float speed = 200f;
public float rotationSpeed = 180f;
public float tiltFactor = 8f;
public bool normalizeVelocity = false;
CharacterController cc;
Vector3 velocity;
Transform armatureBody;
void Start()
{
cc = GetComponent<CharacterController>();
armatureBody = transform.GetChild(0);
}
void Update()
{
velocity = new Vector3(Input.GetAxis("Horizontal"), 0,
Input.GetAxis("Vertical"));
}
void FixedUpdate()
{
if ((velocity != Vector3.zero))
{
var ccVelocity = cc.velocity; // CharacterController velocity. This might be the problem, but without it I cannot rotate the object towards the actual forward velocity.
Quaternion toRotation;
toRotation = Quaternion.LookRotation(ccVelocity, Vector3.up);
transform.rotation = Quaternion.RotateTowards(transform.rotation, toRotation, rotationSpeed * Time.deltaTime);
if (Input.GetKey(KeyCode.S)) print("new toRotation: " + toRotation);
armatureBody.localEulerAngles = new Vector3(velocity.z * tiltFactor, 0, -velocity.x * tiltFactor); // Tilt Body towards velocity This causes the weirdest and most consistest twitching bugs when the tilt is backwards so the object is moving backwards, maybe because im using LookRotation to look backwards?
}
velocity = Quaternion.Euler(0, transform.eulerAngles.y, 0) * velocity; // forward is always forward
cc.SimpleMove(velocity * Time.deltaTime * speed);
}
}
This script does 4 things,
get the velocity from player input.
rotate the main Object(this script) towards the velocity
add tilt towards the velocity, to the child armatureBody, this is a t Pose character in my case.
move the main Object this script is on.
Any help would be appreciated.
I tried removing the vector3 != Zero check, I tried normalizing the vectors, and I tried using a different Quaternion rotation method, but all with the same faulty results.

Check in Update() if Input.forward > threshold if so rotate to velocity. Dont rotate to velocity when only going sideways or backwards, so we can now strafe sideways and walk backwards when standing still or run and rotate to our velocity with the AD keys when running.
void Update()
{
velocity = new Vector3(Input.GetAxis("Horizontal"), 0,
Input.GetAxis("Vertical"));
if (velocity.z > 0.2f)
{
forwardVelocityThreshold = true;
}
else forwardVelocityThreshold = false;
}
Then in our FixedUpdate() we check for that bool and apply the rotateToVelocity if true.
Adjust the following if statement:
if (ccVelocity != Vector3.zero && forwardVelocityThreshold)
{
toRotation = Quaternion.LookRotation(ccVelocity, Vector3.up);
transform.rotation = Quaternion.RotateTowards(transform.rotation, toRotation, rotationSpeed * Time.fixedDeltaTime);
}
Now it works as intended, I also changed the deltaTime to FixedDeltaTime as suggested by Voidsay in the comments, although I have heard conflicting things about this. Some say FixedUpdate always uses fixedDeltaTime even if you are using deltaTime, other say no, always use fixedDeltaTime in FixedUpdate.

Set rigidbody.velocity to direction of mouse in Unity2d: Updated Version

Yes I know this question was asked before by SuperSonyk! That post is here:
Set rigidbody.velocity to direction of mouse in Unity2d
However- the link referenced in the answer to that post is now legacy material, and I can't bring myself to understand it in Unity's current version.
My Problem: In short, I want to make my player accelerate in the direction of my cursor. My game is currently a TOP-DOWN Space Shooter in 2D. My player already looks at my mouse correctly, using cam.ScreenToWorldPoint. But relentlessly trying to add force seems futile for me, since I am fairly new to coding.
If I have any other issues in my code, It would be great if anyone could point them out!
Here's my code:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class PlayerController : MonoBehaviour
{
//================= MOVEMENT =====================
private float thrust = 0.5f;
private float maxSpeed = 10f;
public Rigidbody2D rb;
//================= AIMING =======================
public Camera cam;
Vector2 mousePos;
// Update is called once per frame: Good for INPUTS
void Update()
{
//aiming
mousePos = cam.ScreenToWorldPoint(Input.mousePosition);
}
// Called Set amount of times. Good for PHYSICS CALCULATIONS
void FixedUpdate()
{
Move();
speedLimiter();
//aim
Vector2 lookDirection = mousePos - rb.position;
float angle = Mathf.Atan2(lookDirection.y, lookDirection.x) * Mathf.Rad2Deg - 90f;
rb.rotation = angle;
}
//======= MY MOVE FUNCTION DOES NOT WORK. HELP? ======
void Move()
{
if (Input.GetButtonDown("Accelerate"))
{
rb.velocity = new Vector3(0, thrust, 0) * Time.deltaTime;
}
}
void speedLimiter()
{
if (rb.velocity.magnitude > maxSpeed)
{
rb.velocity = Vector3.ClampMagnitude(rb.velocity, maxSpeed);
}
}
}
Please summarize the edits clearly, thank you!

In general since this is a 2D rigidbody also the velocity is a Vector2 and you should probably rather use Vector2.ClampMagnitude
and then in
rb.velocity = new Vector3(0, thrust, 0) * Time.deltaTime;
do you only want to move in global Y direction? Also a velocity is already a "per second" value -> it makes no sense to multiply by Time.deltaTime if you reassign a new velocity. Since it says thrust I guess you rather wanted to add to the existing velocity.
What you would rather do is save your mouse direction you already have and do
public class PlayerController : MonoBehaviour
{
...
void FixedUpdate()
{
// I would update the aim BEFORE moving
// Use a NORMALIZED direction! Makes things easier later
Vector2 moveDirection = (mousePos - rb.position).normalized;
float angle = Mathf.Atan2(moveDirection.y, moveDirection.x) * Mathf.Rad2Deg - 90f;
rb.rotation = angle;
// OPTIONAL: Redirect the existing velocity into the new up direction
// without this after rotating you would still continue to move into the same global direction
rb.velocity = rb.velocity.magnitude * moveDirection;
Move(moveDirection);
speedLimiter();
}
void Move(Vector2 moveDirection)
{
if (Input.GetButtonDown("Accelerate"))
{
// Instead of re-assigning you would probably add to the existing velocity
// otherwise remove the "+" again
rb.velocity += moveDirection * thrust * Time.deltaTime;
}
}
void speedLimiter()
{
if (rb.velocity.magnitude > maxSpeed)
{
// You are working with Vector2 so use the correct method right away
rb.velocity = Vector2.ClampMagnitude(rb.velocity, maxSpeed);
}
}
}

You already have half of the work by having your player looking at the mouse. We will be using the vector lookDirection as the direction of the movement for the player, normalize it so its length is 1 and multiply it by thrust. This way, we have a vector in the direction of the mouse and of length thrust as intended.
void Move()
{
if (Input.GetButtonDown("Accelerate"))
{
Vector2 lookDirection = (mousePos - rb.position);
rb.AddForce(lookDirection.normalized * thrust);
}
}
Note that we work here with Vector2 since you are using a Rigidbody2D.
Also, I don't think that using Time.DeltaTime is relevant here. When you apply force to a physic object, you don't need to use it, by definition, the function FixedUpdate() has a fixed frequency. If you look at one of Unity's tutorial, you can see that they don't multiply it by Time.DeltaTime
Last tip: you may want to be playing around with the drag property of your Rigidbody2D to have your player slow down over time when not accelerating, otherwise, it will be sliding out of control and the player won't be able to stop it.
Don't hesitate to tell me if my answer is not clear for you or does not entirely satisfy you, it's my first answer here!
EDIT: I forgot to tell you but as derHugo mentioned, since you are using Rigidbody2D, you must use Vector2.ClampMagnitude to limit your speed in your speedLimiter function. Also, I don't think that you need your if since the function Vector2.ClampMagnitude will only change the value of the velocity if it exceeds the maximum.

Thanks to everyone who responded!
With the help of Brackeys community, I managed to solve this by using this method:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class PlayerController : MonoBehaviour
{
//================= MOVEMENT =====================
private float thrust = 10f;
private float maxSpeed = 100f;
public Rigidbody2D rb;
//================= AIMING =======================
public Camera cam;
Vector2 mousePos;
// Update is called once per frame: Good for INPUTS
void Update()
{
//aiming
mousePos = cam.ScreenToWorldPoint(Input.mousePosition);
}
// Called Set amount of times. Good for PHYSICS CALCULATIONS
void FixedUpdate()
{
Move();
speedLimiter();
//aim
Vector2 lookDirection = mousePos - rb.position;
float angle = Mathf.Atan2(lookDirection.y, lookDirection.x) * Mathf.Rad2Deg - 90f;
rb.rotation = angle;
}
void Move()
{
if (Input.GetKey("up"))
{
rb.AddRelativeForce(Vector2.up*thrust);
}
}
void speedLimiter()
{
if (rb.velocity.magnitude > maxSpeed)
{
rb.velocity = Vector3.ClampMagnitude(rb.velocity, maxSpeed);
}
}
//rb.AddForce(new Vector3(0, thrust, 0));
}

Unity C#: Issue with rotating, now facing wrong direction

I have a character/rigidbody and 'she' can turn around. When I press Play in Unity, if I move forward/backward, that's fine, she moves forward/backward. It's a good start.
But then if I turn her left or right, then go forward/backward, she now moves sideways.
She is a rigidbody component set as a parent in the scene.
Surely it's not difficult to do, but I can't figure out how to set her rotation so that when she turns, she will move 'forward' when I press the button to move her forward! There are plenty of first-person-shooter games where you can turn and move 'forward' and the player goes in the correct direction.
My rotation script at the moment is this:
Vector3 EulerAngleVelocity;
public float rotateSpeed = 250.0f;
void Update() {
if (Input.GetKey(KeyCode.UpArrow) || Input.GetKey(KeyCode.DownArrow))
{
MoveVector = PoolInput();
Move();
}
if (Input.GetKey(KeyCode.RightArrow))
{
EulerAngleVelocity = new Vector3(0, rotateSpeed, 0);
Quaternion deltaRotation = Quaternion.Euler(EulerAngleVelocity * Time.deltaTime);
rigidbody.MoveRotation(rigidbody.rotation * deltaRotation);
}
}
private void Move()
{
rigidbody.AddForce((MoveVector * moveSpeed));
}
private Vector3 PoolInput()
{
Vector3 dir = Vector3.zero;
dir.x = joystick.Horizontal();
dir.z = joystick.Vertical();
if (dir.magnitude > 1)
dir.Normalize();
return dir;
}

You're moving your joystick and adding that direction in relation to the WORLD instead of in relation to your player. If you want to add force relative to the orientation of the RigidBody probably what you want to use is rigidBody.AddRelativeForce (documentation) instead of simply rigidBody.AddForce.

Your problem isn't your rotation code, it's your movement code. You're applying a motion in world-space, not local-space ('object'-space).
For example, if you're using Vector3.Forward, you will want to use transform.Forward instead.

Unity - Using a rigidbody for motorcycle - how do I turn?

I'm new to Unity and rigidbodies, and I thought I'd learn by trying to make a 3D Tron Light-cycle game. I've made my player vehicle using a combination of cylinders, spheres, and rectangles, seen below:
I used a rigid body on the elongated sphere, and used the following code:
public float accel = 1.0f;
// Use this for initialization
void Start () {
cycleSphere = GetComponent<Rigidbody>();
}
void FixedUpdate () {
cycleSphere.velocity = Vector3.forward * accel;
}
That moves the vehicle forwards. I'm not sure if there's a better way to do this, but if there is, please do say so.
I've attached the Main camera to the vehicle, and disabled X rotation to prevent it and the camera from rolling.
Now I would like to get it to turn by pressing the A and D buttons. Unlike the 90 degree turning of the original Tron light-cycles, I wanted it to turn like a regular vehicle.
So I tried this:
void Update () {
if (Input.GetKey (KeyCode.A)) {
turning = true;
turnAnglePerFixedUpdate -= turnRateAngle;
} else if (Input.GetKey (KeyCode.D)) {
turning = true;
turnAnglePerFixedUpdate += turnRateAngle;
} else {
turning = false;
}
}
void FixedUpdate () {
float mag = cycleSphere.velocity.magnitude;
if (!turning) {
Quaternion quat = Quaternion.AngleAxis (turnAnglePerFixedUpdate, transform.up);// * transform.rotation;
cycleSphere.MoveRotation (quat);
}
cycleSphere.velocity = Vector3.forward * accel;
}
While the above code does rotate the vehicle, it still moves in the last direction it was in - it behaves more like a tank turret. Worse, pressing either A or D too much would cause it to rotate in the desired direction and, after a short while, go nuts, rotating this way and that, taking the camera with it.
What did I do wrong and how can I fix it?

First of all I would recommend you to change from Input.GetKey to Input.GetAxis which will gracefully increase or decrease it's value when the key is pressed. This will give you the option to normalize the force vector applied as your velocity. Then based on that vector you have to adapt your force input so that the "front wheel" will "drag" the rest of the body to some other direction ( left or right ). This is not the ideal "real world physics behavior" because the forward force is slightly bigger than the side ( left or right ) force.
code example :
// member fields
float sideForceMultiplier = 1.0f;
float frontForceMultiplier = 2.0f;
Vector3 currentVeloticy = Vector3.zero;
void Update()
{
Vector3 sideForce = (sideForceMultiplier * Input.GetAxis("horizontal")) * Vector3.right;
Vector3 frontForce = frontForceMultiplier * Vector3.forward;
currentVelocity = (sideForce + fronForce).Normalize;
}
void FxedUpdate()
{
cycleSphere.velocity = currentVelocity * accel;
}

Gravity not working in unity RigidBody 2D transform

I made sprite and applied rigidbody 2d component, it's working fine as it should, now i wrote this piece of code but, when i start playing the game it working for some period of time but after that, gravity seems be null, means my rigidbody does not come down when i leave the keys
// Update is called once per frame
void Update () {
if (Input.GetKey (KeyCode.LeftArrow)) {
posX--;
} else if (Input.GetKey (KeyCode.RightArrow)) {
posX++;
}
if (Input.GetKey (KeyCode.UpArrow)) {
posY++;
} else if (Input.GetKey (KeyCode.DownArrow)) {
posY--;
}
angle -= Input.GetAxis ("Horizontal");
angle = Mathf.Clamp (angle, -10, 10);
}
void FixedUpdate()
{
transform.eulerAngles = new Vector3 (0,0,angle);
transform.position = new Vector2 (posX * Time.deltaTime, posY * Time.deltaTime);
}
}
what i want to do is move the helicopter left right up and down(which user can control) but when user is not interacting, i want gravity to work as default and helicopter will come down due to gravity, how to achieve that?

You are overwriting the position on every frame, so it doesn't meter what Unity calculates on its physics, you overwrite when you do this:
transform.position = new Vector2 (posX * Time.deltaTime, posY * Time.deltaTime);
I don't know what you want to achieve, but maybe it will work if after this you re-apply a gravity force with traforme.AddForce(), using the object's mass and the gravity acceleration constant.

You should use AddForce instead of Changing x and Y axes.
You can see the example here,
AddFource Example