Unity Universal Turret Script

Turret.cs

using UnityEditor;
using UnityEngine;


public class Turret : MonoBehaviour
{
    [Range(0, 180f)] public float angle = 45f;

    public float maxTurnSpeed = 90f;

    public Transform target;

    [HideInInspector] public bool outOfRange;
    [HideInInspector] public bool aimed;

    void OnDrawGizmos()
    {
#if UNITY_EDITOR
        var range = 20f;
        var dashLineSize = 2f;
        var turret = transform;
        var origin = turret.position;
        var hardpoint = turret.parent;
        
        if (!hardpoint) return;
        var from = Quaternion.AngleAxis(-angle, hardpoint.up) * hardpoint.forward;
        
        Handles.color = new Color(0, 1, 0, .2f);
        Handles.DrawSolidArc(origin, turret.up, from, angle * 2, range);

        if (!target) return;
        
        var projection = Vector3.ProjectOnPlane(target.position - turret.position, hardpoint.up);

        // projection line
        Handles.color = Color.white;
        Handles.DrawDottedLine(target.position, turret.position + projection, dashLineSize);
        
        // do not draw target indicator when out of angle
        if (Vector3.Angle(hardpoint.forward, projection) > angle) return;
        
        // target line
        Handles.color = Color.red;
        Handles.DrawLine(turret.position, turret.position + projection);
        
        // range line
        Handles.color = Color.green;
        Handles.DrawWireArc(origin, turret.up, from, angle * 2, projection.magnitude);
        Handles.DrawSolidDisc(turret.position + projection, turret.up, .5f);
#endif
    }

    void Update()
    {
        Aim(target.position);
    }

    void Aim(Vector3 targetPoint)
    {
        var turret = transform;
        var hardpoint = turret.parent;

        var direction = targetPoint - turret.position;
        direction = Vector3.ProjectOnPlane(direction, hardpoint.up);
        var signedAngle = Vector3.SignedAngle(hardpoint.forward, direction, hardpoint.up);

        outOfRange = false;
        if (Mathf.Abs(signedAngle) > angle)
        {
            outOfRange = true;
            direction = hardpoint.rotation * Quaternion.Euler(0, Mathf.Clamp(signedAngle, -angle, angle), 0) *
                        Vector3.forward;
        }

        var rotation = Quaternion.LookRotation(direction, hardpoint.up);

        aimed = false;
        if (rotation == transform.rotation && !outOfRange)
        {
            aimed = true;
        }

        transform.rotation = Quaternion.RotateTowards(transform.rotation, rotation, maxTurnSpeed * Time.deltaTime);
    }
}