Develop Reference

How can I rotate a steering wheel to its original rotation in Unity3D?

I have been searching for an answer for hours, and I cant find the solution. I have a script that rotates a steering wheel when the car is turning. It has maximum rotation of 120 and a minimum rotation of -120. I have been trying to rotate with RotateTowards and other Quaternion methods but I can't figure them out. How can I make it when the turning angle is not zero and turning keys (a and d) are not pressed, it goes to its original rotation of 0, 0, 0, at a certain speed?
Here's my script for the steering wheel:
if (horizontalInput > 0)
{
wheel.transform.Rotate(Vector3.forward*Time.deltaTime*wheelspeed);
rotations -= wheelspeed;
}
else if (horizontalInput < 0)
{
wheel.transform.Rotate(-Vector3.forward * Time.deltaTime * wheelspeed);
rotations += wheelspeed;
}
And here is my (very bad) script for the minimum and maximum rotation of the steering wheel:
angle += Input.GetAxis("Horizontal") * Time.deltaTime*10;
angle = Mathf.Clamp(-120, angle, 120);
wheel.transform.localRotation = Quaternion.AngleAxis(angle, Vector3.forward);
angle += Input.GetAxis("Horizontal") * Time.deltaTime * 400;
angle = Mathf.Clamp(120, 0, angle);
wheel.transform.localRotation = Quaternion.AngleAxis(angle, Vector3.forward);

You should do something like this for the steering wheel script:
float rotateBack = 0f;
float angle = 0f;
void Update(){
angle += Input.GetAxis(“Horizontal”) * Time.deltaTime * 10;
angle = Mathf.Clamp(angle, -120, 120);
if (Input.GetAxis(“Horizontal”) == 0 && angle != 0f){
angle += rotateBack * Time.deltaTime;
if (angle > 0){
rotateBack = -10f;
}
else{
rotateBack = 10f;
}
}
transform.rotation = Quaternion.Euler(0f, 0f, angle);
}
What this does is setting a variable of angle to the input times a value to increase turning speed. Then it clamps if so it doesn’t go over 120, or under -120. Then, if there is no input and the angle isn’t zero: it will change the variable by how much to rotate back. The rotate back variable is set to either positive or negative based on which direction the steering wheel needs to be turned. The only problem with this script that I could see is the angle not being exactly 0, continuing the if statement. If this error affects your game, use the Mathf.Round(); function.
(If there are any errors, comment on this post.)

I would do what #ken is doing, but refactor the speed factors and other constants into fields so they are more easily changed and also use Mathf.MoveTowardsAngle to move the angle back to its neutral position.
[SerializeField] float rotateBackSpeed = 3f; // degrees per second
[SerializeField] float rotateSpeed = 10f; // degrees per second
[SerializeField] float angle = 0f; // degrees
[SerializeField] float minAngle = -120f; // degrees
[SerializeField] float maxAngle = 120f; // degrees
[SerializeField] float neutralAngle = 0f; // degrees
void Update()
{
angle = Mathf.Clamp(angle + Input.GetAxis(“Horizontal”) * rotateSpeed
* Time.deltaTime, minAngle, maxAngle);
if (Mathf.Approximately(0f, Input.GetAxis(“Horizontal”)))
{
angle = Mathf.MoveTowardsAngle(angle, neutralAngle,
rotateBackSpeed * Time.deltaTime);
}
transform.eulerAngles = angle * Vector3.forward;
}

After rotation, whenever I move left or right now, it goes in the opposite direction

After rotation, whenever I move left or right now, it goes in the opposite direction.
Hi I'm trying to rotate my object by 90 degrees every time I press a button and it works but now when I press the right arrow, it moves left and vice versa. Can anyone help me with this? Thank you
public class PlayerMovement : MonoBehaviour
{
[SerializeField] private float _playerSpeed=1.5f;
[SerializeField] private float _playerRotation = 90f;
// Start is called before the first frame update
void Start()
{
transform.position = new Vector2(0,8f);
}
// Update is called once per frame
void Update()
{
float horizontalInput = Input.GetAxis("Horizontal");
float VerticalInput = Input.GetAxis("Vertical");
float smooth = 100f;
if (Input.GetKeyDown(KeyCode.UpArrow))
{
transform.rotation = Quaternion.Lerp(transform.rotation, Quaternion.Euler(0, 0, _playerRotation), Time.time * smooth);
_playerRotation += 90f;
}
else if(horizontalInput !=0 || VerticalInput<=0)
{
Vector2 direction = new Vector2(horizontalInput, VerticalInput);
transform.Translate(direction * _playerSpeed * Time.deltaTime);
}
}
}

There are a number of issues with your code.
You had:
// Update is called once per frame
void Update()
{
float horizontalInput = Input.GetAxis("Horizontal");
float VerticalInput = Input.GetAxis("Vertical");
float smooth = 100f;
if (Input.GetKeyDown(KeyCode.UpArrow))
{
transform.rotation = Quaternion.Lerp(transform.rotation, Quaternion.Euler(0, 0, _playerRotation), Time.time * smooth);
_playerRotation += 90f;
}
The first issue is that you only modify the transform.rotation ONCE per keypress, and that modification is only a fraction of the full intention because of the lerp. You need to pull the lerp outside of the if KeyDown check.
Second issue is a little moot as resolving the first issue will also resolve the second: You are setting _playerRotation after applying it to the transform. There are edge cases where this is sometimes correct, but I suspect this is not one of them.
Third, the lerp factor (Time.time * smooth). This is a BLEND factor and should only scale from zero to one (again, some edge cases as exceptions but this isn't one of them). Time.time on its own is going to be >1 after the first second of runtime. I expect your intention here was to animate the rotation over time, but this is done by accumulating Time.deltaTime.

Tilt first person camera's z axis while turning

I am working on controls for a bipedal tank, that has a boost/dash feature.
When the boost/dash mode is activated by holding a button the tank changes from a traditional WASD strafing movement to something like a jet fighter but on ground.
Now when the player tries to turn while boosting the camera needs to tilt with the turning direction to make it feel smoother.
Here is a video clip showing my problem
This is the script added to the main camera
public class PlayerCameraTilt : MonoBehaviour
{
private Camera viewCam;
private CharacterController characterController;
public float tiltAmount = 10f;
private void Start()
{
viewCam = GetComponent<Camera>();
characterController = GetComponentInParent<CharacterController>();
}
private void Update()
{
if (characterController.GetComponent<PlayerController>().movementState == MovementModes.boost)
{
float inputValue = Input.GetAxis("MoveHorizontal") * tiltAmount;
Vector3 euler = transform.localEulerAngles;
euler.z = Mathf.Lerp(euler.z, -inputValue, 5f * Time.deltaTime);
transform.localEulerAngles = euler;
}
else
{
Vector3 euler = transform.localEulerAngles;
euler.z = Mathf.Lerp(euler.z, 0f, 5f * Time.deltaTime);
transform.localEulerAngles = euler;
}
}
}
It kind of works, BUT only in one rotation direction, namely the positive one. If i turn the other way the angle becomes negative and does a whole 360 degree rotation until it ends up at 0 degrees.
I tried around with the built in Quaternion methods like Quaternion.Rotate() or Quaternion.AngleAxis()
but they didn't work because Quaternion.Rotate() doesn't tilt the Camera but completely rotates it. Quaternion.AngleAxis() works with the whole tilt angle limit but also does something to the other axis which i don't want to modify.
Is there a way to prevent the camera from doing a complete 360° rotation when the axis input becomes negative and just tilt in a slight angle?

Wraparound issues aside, the z component is "applied" first among the euler components, so I wouldn't modify it directly like that in this application.
Instead, I would convert the input to an angle to lean, rotate the direction of the local up before localRotation is applied (Quaternion.Inverse(transform.localRotation) * transform.up) by that angle, then use Quaternion.LookRotation to find a rotation with the current forward and that up, then use Quaternion.Slerp to slerp toward that rotation:
private void Update()
{
if (characterController.GetComponent<PlayerController>().movementState == MovementModes.boost)
{
float inputValue = Input.GetAxis("MoveHorizontal") * tiltAmount;
Vector3 upOfParent = Quaternion.Inverse(transform.localRotation) * transform.up;
Vector3 upDir = Quaternion.AngleAxis(-inputValue, transform.forward) * upOfParent;
Quaternion goalRot = Quaternion.LookRotation(transform.forward, upDir);
transform.rotation = Quaternion.Slerp(transform.rotation, goalRot, 5f * Time.deltaTime);
}
else
{
float inputValue = Input.GetAxis("MoveHorizontal") * tiltAmount;
Vector3 upOfParent = Quaternion.Inverse(transform.localRotation) * transform.up;
Quaternion goalRot = Quaternion.LookRotation(transform.forward, upOfParent);
transform.rotation = Quaternion.Slerp(transform.rotation, goalRot, 5f * Time.deltaTime);
}
}
Just keep in mind that using t = 5f * Time.deltaTime for lerp/slerp operations does not always guarantee that the output will ever equal the to parameter.

Mathf.clamp() function in Unity

I have a Cube(Player) in my game scene. I have written a C# script to constrain the movement(using Mathf.Clamp()) of the Cube so it does not leave the screen.
Below is my FixedUpdate() method from the Script
private void FixedUpdate()
{
float moveHorizontal = Input.GetAxis("Horizontal");
float moveVertical = Input.GetAxis("Vertical");
Vector3 movement = new Vector3(moveHorizontal, 0.0f, moveVertical);
rb.velocity = movement * speed;
rb.position = new Vector3(
Mathf.Clamp (rb.position.x, x_min, x_max),
0.5f,
Mathf.Clamp(rb.position.z, z_min, z_max)
);
}
Values of x_min, x_max, z_min, z_max are -3, 3, -2, 8 respectively inputted via the unity inspector.
PROBLEM
The script is working fine but my player(Cube) can move up to -3.1 units in negative X-AXIS (if I keep pressing the left arrow button) which is 0.1 units more in negative X-AXIS(This behavior is true for other axes too). It obviously clamps -3.1 to -3 when I stop pressing the button.
Why is this happening? Why doesn't it(Mathf.Clamp()) restrict the Cube to -3 units in first place?
Why am I getting that extra 0.1 units?
And Why is this value 0.1 units only? Why not more or less?

Your issue could be caused because you are setting velocity and then position, but before the next frame unity adds the velocity to your objects position. Which is why it ends up 0.1 units off.
To fix this, try resetting the velocity of the object to zero if it's about to leave your boundaries.

This is happening because the internal physics update moves the cube after you have put it in its clamped position. Mathf.Clamp() does restrict the cube to the expected position in the first place, as you can verify by putting a Debug.Log directly after you assign the position
You are getting the extra .1 units because you give the object a speed that gets applied after you clamp
It is 0.1 units because of the speed and the setting for Fixed Timestep (in Project Settings > Time). If you would set a higher speed it would be more. If you would lower the Fixed Timestep it would also be a bit more.

You already got the reason why this happens.
In order to fix the problem, you can use this code to prevent the cube to go outside your boundaries:
private void FixedUpdate() {
Vector3 movement = new Vector3(Input.GetAxis("Horizontal"), 0f, Input.GetAxis("Vertical"));
// Get new position in advance
float xPos = rb.position.x + movement.x * speed * Time.fixedDeltaTime;
float zPos = rb.position.z + movement.z * speed * Time.fixedDeltaTime;
// Check if new position goes over boundaries and if true clamp it
if (xPos > x_max || xPos < x_min) {
if (xPos > x_max)
rb.position = new Vector3(x_max, 0, rb.position.z);
else
rb.position = new Vector3(x_min, 0, rb.position.z);
movement.x = 0;
}
if (zPos > z_max || zPos < z_min) {
if (zPos > z_max)
rb.position = new Vector3(rb.position.x, 0, z_max);
else
rb.position = new Vector3(rb.position.x, 0, z_min);
movement.z = 0;
}
rb.velocity = movement * speed;
}

Camera rotation in maze game depending of accelerometer

I'm still newbie to Unity... I'm trying to develop simple maze game. I want to roll my ball through maze, but I have to rotate camera left or right, otherwise the player can't see what's behind while rolling the ball on the left or on the right.
void Start ()
{
offset = transform.position - player.transform.position;
}
void LateUpdate()
{
transform.position = player.transform.position + offset;
}
I'm using low pass filter for accelerometer values:
Vector3 lowpass()
{
float LowPassFilterFactor = AccelerometerUpdateInterval / LowPassKernelWidthInSeconds;
lowPassValue = Vector3.Lerp(lowPassValue, Input.acceleration, LowPassFilterFactor);
return lowPassValue;
}
Accelerometer values are from -1 to 1 for each coordinate. Because of that I check my lowPassValue.x value and limit it. If it's positive ( >0.3 ), then the camera should turn right and if it's negative ( <-0.3 ) then camera should turn left.
Quaternion rotation = Quaternion.AngleAxis(45, Vector3.up* Time.deltaTime) ; // right
transform.rotation = rotation;
Quaternion rotation = Quaternion.AngleAxis(-45, Vector3.up * Time.deltaTime) ; // left
transform.rotation = rotation;
But then my offset doesn't work anymore, I can't see ball anymore. And camera rotation doesn't work as it should.
Is there any better solution for this or I'm using the wrong function?
Any help will be very appreciated!

You have a problem with your AngleAxis() where you are multiplying the Axis to rotate on, by Time.deltaTime. this means that essentially you are changing the axis of rotation, and it is unpredictable. Most likely you wont get your "Right" or "Left" rotation. Multiply deltaTime by the angle itself instead.
Also, Quaternions are to be multiplied if you want to apply an angle with them:
Quaternion rotation = Quaternion.AngleAxis(45 * Time.deltaTime, Vector3.up) ; // right
transform.rotation *= rotation;
Quaternion rotation = Quaternion.AngleAxis(-45 * Time.deltaTime, Vector3.up) ; // left
transform.rotation *= rotation;
or this could just be achieved as:
transform.Rotate(45 * Vector3.right * Time.deltaTime); // right
transform.Rotate(45 * -Vector3.right * Time.deltaTime); // left