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Camera Jitter on Rotation (not movement)

My camera jitters on rotation, but not movement. This script is the only asset in a new project, and it's attached to the camera - it's supposed to be a free-flying camera. I added a few cubes into the environment so I could check it was moving correctly, and it stutters several times a second whenever it's rotated. Movement works just fine.
I've tried changing camera clipping planes, I've tried moving either movement or rotation or both into Update() instead, removing the default camera and adding my own, and since it's an otherwise empty project I'm showing over 500fps so don't have any performance issues - nothing has had any effect, for better or worse.
Any suggestions welcome! If someone has a minute to open up a default project and slap this script on the camera and make sure it's not something on my end, that would at least rule that out and I'd really appreciate it. Thanks in advance.
public class CameraController : MonoBehaviour
{
public Vector2 mouseSensitivity = Vector2.one;
public Vector3 moveSensitivity = Vector2.one;
public Transform camTransform;
Vector3 camEulers = Vector3.zero;
void Start()
{
camTransform = FindObjectOfType<Camera>().transform;
}
void LateUpdate()
{
KeyboardMovement();
LockedMouseRotation();
}
void KeyboardMovement()
{
camTransform.position += Input.GetAxis( "Vertical" ) * camTransform.forward * Time.deltaTime * moveSensitivity.y;
camTransform.position += Input.GetAxis( "Horizontal" ) * camTransform.right * Time.deltaTime * moveSensitivity.x;
}
void LockedMouseRotation()
{
camEulers.x -= Input.GetAxis( "Mouse Y" ) * mouseSensitivity.y * Time.deltaTime;
camEulers.y += Input.GetAxis( "Mouse X" ) * mouseSensitivity.x * Time.deltaTime;
camEulers.x = Mathf.Clamp( camEulers.x, -90.0f, 90.0f );
camTransform.rotation = Quaternion.Euler( camEulers );
}
}

Don't use Time.deltaTime here.
Your goal here is to convert measurements of linear distance (GetAxis("Mouse X") and GetAxis("Mouse Y")) into a measurement of angular distance (the angular distance you are using to adjust the camera's Euler angles). For that you only need a constant factor, which can be your mouseSensitivity components.
But GetAxis gets multiplied by Time.deltaTime in other places and works perfectly fine. Why do those work like that?
Your goal is not converting to distance from "throttle position" like one might from GetAxis("Horizontal") or GetAxis("Vertical") or GetAxis("customKeyButtonOrThrottleAxis") . That is a situation where you would want to multiply by a time (Time.deltaTime) to calculate a distance if you are using the position of the button or throttle as velocity. This is because distance = speed * time.
In some cases you might multiply by Time.deltaTime to calculate a velocity or speed if the button or throttle is to represent acceleration, because speed = acceleration * time.
Okay, so why doesn't Time.deltaTime work here?
When you use GetAxis("Mouse X") or GetAxis("Mouse Y"), you get a measurement of pixel difference in position since the last frame.
The typical way a mouse driven camera works in games is that moving the mouse the same distance in the same direction should move the camera the same way (assuming you don't move the camera all they way up or down of course).
So what that means is that multiplying by Time.deltaTime does here is often actually the opposite of what you might expect - moving the mouse the same distance moves the camera's rotation differently depending on how many frames that movement occurred over and how quickly those frames were rendered.
The faster the frames were rendered (that means, a smaller Time.deltaTime), the less camera rotation the same mouse distance becomes. This results in unpredictable jitter especially when the very act of moving the camera can drastically change the framerate.
So how do I fix it then?
So, the only thing you need to do here is to remove the multiplication by Time.deltaTime:
camEulers.x -= Input.GetAxis( "Mouse Y" ) * mouseSensitivity.y;
camEulers.y += Input.GetAxis( "Mouse X" ) * mouseSensitivity.x;
A similar situation where you might want to include Time.deltaTime is if you want to calculate the speed or velocity of the mouse movement.
But, in that case, you would want to divide by Time.deltaTime. This is because speed = distance / time.
Vector2 mouseVelocity = Vector2.Scale(mouseSensitivity,
new Vector2(Input.GetAxis("Mouse X"),
Input.GetAxis("Mouse Y"))
) / Time.deltaTime;
In most cases, you probably don't want to be concerned with the speed/velocity of the mouse movement. But, for example, those interested in a super monkey ball type game using a track ball input might find this side bit useful!

Unity: Can't get object's z axis to lock when facing camera

I want a sprite to always face the camera, except in the Z-Axis. My sprites keep tipping left or right when I move the camera, and I can't have that.
I have been googling this for hours. I've tried transform.LookAt or Quaternion.LookRotation and manually setting the z to 0, but for whatever reason the z keeps adjusting. I've seen and tried so many solutions that feel like they should work but just don't. If it matters, my sprite is a child of another object, but trying localRotation doesn't work either. Freezing rigidbody constraints also has no effect.
The most accurate I can get it is this:
public class Billboard : MonoBehaviour
{
GameObject cam;
float minDist;
// Start is called before the first frame update
void Start()
{
cam = GameObject.Find("Main Camera");
}
// Update is called once per frame
void LateUpdate()
{
//Scale
minDist = cam.GetComponent<CameraOrbit>().distanceMin;
transform.localScale = new Vector3(1f, 1f, 1f) * (cam.GetComponent<CameraOrbit>().distance - minDist) * 1.01f / 3;
//Direction
transform.LookAt(cam.transform.position);
Vector3 rot = transform.rotation.eulerAngles;
transform.rotation = Quaternion.Euler(rot.x, rot.y, 0);
}
}
With this I can get the sprite to face the camera, but the z axis refuses to stay at zero.

Special thanks to StarManta for answering this question on the Unity Forums.
"OK, I think I see what's happening. Them looking like they're rotated is, I think, an illusion; I think they really are accurately pointing at the camera and right-side-up. But, you're treating the camera as if it has a round/fisheye projection, when it really has a rectilinear projection. Usually this doesn't matter but in this case it does. It's hard to explain exactly how this affects this, but the upshot is that, when things that are on either side of the center of the screen are set to "look towards" the camera, they actually appear to be rotated around their Y axes.
The solution to this is actually annoyingly simple: don't set the rotation to look at the camera, set it to be the same as the camera."
transform.rotation = cam.transform.rotation;

Have you tried rotation constraints?
https://docs.unity3d.com/Manual/class-RotationConstraint.html

I had a similar problem, where I wanted some 3d text to always look up, but rotated to the camera.
What worked for me was setting the undesired euler components to zero after applying the lookat rotation.
In your case, it would be something like this.
transform.LookAt(cam.transform.position);
var rot = transform.rotation.eulerAngles;
transform.rotation = Quaternion.Euler(rot.x, rot.y, 0);
In case you need another z value, just replace the 0.

Unity RotateAround() in combination with a specific direction

I'm trying to rotate my camera around a character, with a certain direction it needs to face. For example, I want my camera to rotate around my character, and stop the rotation when it faces another objects forward axis.
So I figured I needed a combination between RotateAround() and LookRotation().
RotateAround() to rotate the camera around the character, and LookRotation() to make the camera face that object aswell.
The problem is: I don't want my camera to move or rotate away from my character.
I tried a couple of things, the most thought out being this:
private void RotateCamera()
{
Quaternion currentCameraRotation = _camera.transform.rotation;
Quaternion futureCameraRotation = Quaternion.LookRotation(_hitObstacleStartingPoint.transform.forward);
float rotationAngle;
Vector3 rotationAxis;
Quaternion.FromToRotation(currentCameraRotation.eulerAngles, futureCameraRotation.eulerAngles).ToAngleAxis(out rotationAngle, out rotationAxis);
_camera.transform.RotateAround(_character.transform.position, _camera.transform.up, rotationAngle);
}
But that ended up in my camera rotating all over the place..
Thanks in advance!
EDIT: I'm sorry for my terrible explanation.
Here's a little drawing.

If you calculate the distance between the current rotation angle, and the target rotation angle, and you can rotate around the pivot over time.
See below:
private void RotateCamera()
{
Quaternion currentCameraRotation = _camera.transform.rotation;
Quaternion futureCameraRotation = Quaternion.LookRotation(obstacleObject.transform.forward, obstacleObject.transform.up);
float angleDelta = Quaternion.Angle(currentCameraRotation, futureCameraRotation);
_camera.transform.RotateAround(this._character.transform.position, _camera.transform.up, angleDelta * rotationSpeed * Time.deltaTime);
}
To help visualize what's going on:
void OnDrawGizmos()
{
Gizmos.color = Color.green;
Gizmos.DrawLine(_camera.transform.position, _camera.transform.forward * 20 + _camera.transform.position);
Gizmos.color = Color.red;
Gizmos.DrawLine(obstacleObject.transform.position, obstacleObject.transform.forward * 20 + obstacleObject.transform.position);
}
This doesn't work if your obstacle is rotated around x,z; it's always assuming a identity forward vector.

I ended up using fixed camera points in my scene. It avoids the problem, so I don't consider this one solved, but I have a deadline on this project and I can't afford to spend too much time on this problem anymore. Thanks to those of you who have helped me.

Unity 2D launch gameObject at a specific angle without affecting speed

I am working on a game where i need to shoot the ball at an angle and power defined by 2 sliders (1 angle slider, 1 power slider). I currently have this code to control the launching of the ball:
public void shoot()
{
float angle = angleSlider.GetComponent<Slider>().value;
float power = powerSlider.GetComponent<Slider>().value;
gameObject.SetActive(false);
ball.GetComponent<Rigidbody2D>().simulated = true;
Vector2 releaseVector = Quaternion.AngleAxis(angle, transform.up) * transform.forward;
ball.GetComponent<Rigidbody2D>().velocity = releaseVector * (power/3);
}
with this current code it works almost perfect apart from one thing. When the angle is like between 30 and 60, the ball is launched well but if i set it to 0 degrees the ball would barely move and on the contrary if i set it to 90 degrees, the ball launches with much more power. How can i set a constant speed for all degrees so that the speed is only affected by the power slider only please? Thanks.

Typically, you shouldn't set the velocity of a rigidbody directly. Per the Unity docs...
In most cases you should not modify the velocity directly, as this can result in unrealistic behaviour.
Instead, you usually want to impart a physical impulse to the ball using an API like AddForce or AddRelativeForce

That is easy.. You have to normalize the releaseVector.
ball.GetComponent<Rigidbody2D>().velocity = releaseVector.normalized * (power/3);
Then adjust the power to what you want. That way you will have the direction u wanted and speed depends on the power value.
If you want to know what normalize do, you can find more information here;
https://docs.unity3d.com/ScriptReference/Vector3.Normalize.html

ball reflection angles Xna c#

I'm trying to find a way to handle reflections for a breakout clone.
I would upload an image to the post instead of the following paragraph, however i have not yet gained the privilege of that yet.
If the ball intersects the left hand side i want it to bounce off to the left.
if the ball intersects the right hand side i want it to bounce off to the right. if the ball intersects the middle section i want it to bounce up the way. i want to learn how to make it bounce in a varying direction dependant on what side of the left, right, or middle section was intersected
I would like to not use three separate rectangles for this, i want to learn how to do it with one.
I use a Vector2 for ball velocity, projVel.
It's position is projPos.
A rectangle for the paddle lightRect.
The reason I use proj.collRect for the beginning of the if is because I cannot use the intersect method with Vector2.
This is my makeshift collision handler at present, which does work but the speed changes to an extent which renders the game unplayable. The speed clamp i have only slightly slows it down i think. i have a variable for projSpeed i cannot clamp that or it will never be able to stop.
if (proj.collRect.Intersects(lightSaber.lightRect))
{
proj.projPos.Y = lightSaber.lightRect.Y - proj.projTxr.Height;
proj.projVel.Y *= -1;
proj.projVel.X = 10 * (proj.projPos.X - lightSaber.lightRect.Center.X) / (lightSaber.lightRect.Center.X);
}
proj.projVel.X = Math.Max(-4, Math.Min(proj.projVel.X, 4));
proj.projVel.Y = Math.Max(-4, Math.Min(proj.projVel.Y, 4));
Help me by showing me how I could do this, maybe in the Math. method, or even an alternative to .Intersects so I can use projPos instead of collRect.
I really am not sure where to start, if there is another way I could do it an example would be great.

Instead of manipulating X and Y velocities independently, I recommend that you calculate a reflection angle based on the position and then derive the velocity from the angle and the speed prior to impact.
Example:
// NOTE: this code assumes that positive Y is down
if (proj.collRect.Intersects(lightSaber.lightRect) && projPos.projVel.Y > 0.0f) // only bounce if projectile is moving downward
{
// remember current speed for when we calculate new velocity
var projSpeed = projVel.Length();
// make sure the projectile no longer intersects the bar
proj.projPos = lightRect.Y - proj.projTxr.Height;
// interpolate reflection angle
var t = (proj.projPos.X - lightSaber.lightRect.X) / lightSaber.lightRect.Width;
var reflectDegrees = 150.0f - t * 120f; // straight up +/- 60 degrees
var reflectRadians = reflectDegrees * (float)Math.PI / 180.0f;
// final velocity determined by angle and original projectile speed
proj.projVel = new Vector2((float)Math.Cos(reflectRadians) * projSpeed, -(float)Math.Sin(reflectRadians) * projSpeed);
}