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@KarlRamstedt
Created January 8, 2020 10:17
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A simple First Person Camera rotation script for Unity.
using UnityEngine;
/// <summary>
/// A simple FPP (First Person Perspective) camera rotation script.
/// Like those found in most FPS (First Person Shooter) games.
/// </summary>
public class FirstPersonCameraRotation : MonoBehaviour {
public float Sensitivity {
get { return sensitivity; }
set { sensitivity = value; }
}
[Range(0.1f, 9f)][SerializeField] float sensitivity = 2f;
[Tooltip("Limits vertical camera rotation. Prevents the flipping that happens when rotation goes above 90.")]
[Range(0f, 90f)][SerializeField] float yRotationLimit = 88f;
Vector2 rotation = Vector2.zero;
const string xAxis = "Mouse X"; //Strings in direct code generate garbage, storing and re-using them creates no garbage
const string yAxis = "Mouse Y";
void Update(){
rotation.x += Input.GetAxis(xAxis) * sensitivity;
rotation.y += Input.GetAxis(yAxis) * sensitivity;
rotation.y = Mathf.Clamp(rotation.y, -yRotationLimit, yRotationLimit);
var xQuat = Quaternion.AngleAxis(rotation.x, Vector3.up);
var yQuat = Quaternion.AngleAxis(rotation.y, Vector3.left);
transform.localRotation = xQuat * yQuat; //Quaternions seem to rotate more consistently than EulerAngles. Sensitivity seemed to change slightly at certain degrees using Euler. transform.localEulerAngles = new Vector3(-rotation.y, rotation.x, 0);
}
}
@InsaneGds
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Placed the script in Scripts folder, it still doesn't work. I can't move the player or the camera.

@KarlRamstedt
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@GeoSubZero have you tried attaching it to the camera object?

@InsaneGds
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@KarlRamstedt Yes but it still doesn't works. Only the camera moves, the player is still static.

@KarlRamstedt
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@GeoSubZero ... yes, that's how it's supposed to work. This script is camera rotation only. As indicated by the name.
You'll need to find/make a character controller for movement.

@Romaleks360
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literal strings don't create garbage, they are already interned by the compiler
https://stackoverflow.com/questions/42413654/is-there-any-performance-increase-by-changing-this-net-string-to-a-const-does

that's some extreme premature optimization, never do that.

@KarlRamstedt
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@Romaleks360 Loads of people around the web recommend caching strings in Unity optimization efforts. Check around.
Might be something more specific to the Unity Engine rather than C#.

@andewx
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andewx commented Feb 15, 2024

Thank you so much I was making a flying camera for my game, and I had a problem where the z orientation kept changing. THIS FIXED IT! Again, thank you.

It pains me to say me too, not sure why the Quaternion.Euler() behaves that way.

@andewx
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andewx commented Feb 15, 2024

Karl can you explain why perhaps the Quaternion.Euler() rotation creates off-axis rolls?

@ItsMabb
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ItsMabb commented Mar 22, 2024

Thank you so much. Ive been struggling on this

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