Yet another FPS controller simple script

FpsControl.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class FpsControl : MonoBehaviour {

  protected Vector2 frame_mouse_position;

  public Transform h;
  public Transform v;

  public float move_speed = 1f;
  public float h_speed = 360f;
  public float v_speed = 180f;

  public float viewAngle = 60f;

  protected float dt = 1f;

  void Update()
  {
    dt = Time.deltaTime > 0.1f ? 0.05f : Time.deltaTime;
    //Debug.Log(Time.deltaTime + " : " + dt);

    update_movement();
    update_looking();
  }

  void update_looking()
  {
    Vector2 mouse = new Vector2(Input.GetAxis("Mouse X"), Input.GetAxis("Mouse Y"));
    Vector2 delta = mouse - frame_mouse_position;
    
    if(delta.sqrMagnitude != 0f)
    {
      
      if(delta.x != 0f)
      {
        h.Rotate(Vector3.up, delta.x * h_speed * dt);
      }

      if(delta.y != 0f)
      {
        
        v.Rotate(Vector3.right, -delta.y * v_speed * dt);
        
        //Debug.Log(v.localEulerAngles);

        Vector3 local = v.localEulerAngles;
        if (local.x > viewAngle && local.x < 180f)
        {
          local.y = local.z = 0f;
          local.x = viewAngle;
        }
        if (local.x > 180f && local.x < 360f - viewAngle)
        {
          local.y = local.z = 0f;
          local.x = 360f - viewAngle;
        }
        v.localEulerAngles = local;
      }

    }
  }

  void update_movement() {
    Vector3 dir = Vector3.zero;

    if (Input.GetKey(KeyCode.Q))
    {
      dir.x = -1f;
    }
    else if (Input.GetKey(KeyCode.D))
    {
      dir.x = 1f;
    }

    if (Input.GetKey(KeyCode.Z))
    {
      dir.z = 1f;
    }
    else if (Input.GetKey(KeyCode.S))
    {
      dir.z = -1f;
    }
    
    transform.Translate(dir * move_speed * dt);
  }
}