Stamina/health etc. first person controller with gui

README.md

Refactored and updated to Unity 5 version of the tutorial here.

The FirstPersonController.cs is mostly the standard asset, but did have to change a couple things to enable/disable sprinting and jumping.

FirstPersonController.cs

using System;
using UnityEngine;
using UnityStandardAssets.CrossPlatformInput;
using UnityStandardAssets.Utility;
using Random = UnityEngine.Random;

namespace UnityStandardAssets.Characters.FirstPerson
{
    [RequireComponent(typeof (CharacterController))]
    [RequireComponent(typeof (AudioSource))]
    public class FirstPersonController : MonoBehaviour
    {
        [SerializeField] public bool m_IsWalking;
        [SerializeField] private float m_WalkSpeed;
        [SerializeField] private float m_RunSpeed;
        [SerializeField] [Range(0f, 1f)] private float m_RunstepLenghten;
        [SerializeField] private float m_JumpSpeed;
        [SerializeField] private float m_StickToGroundForce;
        [SerializeField] private float m_GravityMultiplier;
        [SerializeField] private MouseLook m_MouseLook;
        [SerializeField] private bool m_UseFovKick;
        [SerializeField] private FOVKick m_FovKick = new FOVKick();
        [SerializeField] private bool m_UseHeadBob;
        [SerializeField] private CurveControlledBob m_HeadBob = new CurveControlledBob();
        [SerializeField] private LerpControlledBob m_JumpBob = new LerpControlledBob();
        [SerializeField] private float m_StepInterval;
        [SerializeField] private AudioClip[] m_FootstepSounds;    // an array of footstep sounds that will be randomly selected from.
        [SerializeField] private AudioClip m_JumpSound;           // the sound played when character leaves the ground.
        [SerializeField] private AudioClip m_LandSound;           // the sound played when character touches back on ground.

        private Camera m_Camera;
        public bool m_Jump;
        public bool m_CanSprint;
        public bool m_CanJump;
        private float m_YRotation;
        private Vector2 m_Input;
        private Vector3 m_MoveDir = Vector3.zero;
        private CharacterController m_CharacterController;
        private CollisionFlags m_CollisionFlags;
        private bool m_PreviouslyGrounded;
        private Vector3 m_OriginalCameraPosition;
        private float m_StepCycle;
        private float m_NextStep;
        public bool m_Jumping;
        private AudioSource m_AudioSource;

        // Use this for initialization
        private void Start()
        {
            m_CharacterController = GetComponent<CharacterController>();
            m_Camera = Camera.main;
            m_OriginalCameraPosition = m_Camera.transform.localPosition;
            m_FovKick.Setup(m_Camera);
            m_HeadBob.Setup(m_Camera, m_StepInterval);
            m_StepCycle = 0f;
            m_NextStep = m_StepCycle/2f;
            m_Jumping = false;
            m_AudioSource = GetComponent<AudioSource>();
			m_MouseLook.Init(transform , m_Camera.transform);
        }


        // Update is called once per frame
        private void Update()
        {
            RotateView();
            // the jump state needs to read here to make sure it is not missed
            if (!m_Jump && m_CanJump)
            {
                m_Jump = CrossPlatformInputManager.GetButtonDown("Jump");
            }

            if (!m_PreviouslyGrounded && m_CharacterController.isGrounded)
            {
                StartCoroutine(m_JumpBob.DoBobCycle());
                PlayLandingSound();
                m_MoveDir.y = 0f;
                m_Jumping = false;
            }
            if (!m_CharacterController.isGrounded && !m_Jumping && m_PreviouslyGrounded)
            {
                m_MoveDir.y = 0f;
            }

            m_PreviouslyGrounded = m_CharacterController.isGrounded;
        }


        private void PlayLandingSound()
        {
            m_AudioSource.clip = m_LandSound;
            m_AudioSource.Play();
            m_NextStep = m_StepCycle + .5f;
        }


        private void FixedUpdate()
        {
            float speed;
            GetInput(out speed);
            // always move along the camera forward as it is the direction that it being aimed at
            Vector3 desiredMove = transform.forward*m_Input.y + transform.right*m_Input.x;

            // get a normal for the surface that is being touched to move along it
            RaycastHit hitInfo;
            Physics.SphereCast(transform.position, m_CharacterController.radius, Vector3.down, out hitInfo,
                               m_CharacterController.height/2f, ~0, QueryTriggerInteraction.Ignore);
            desiredMove = Vector3.ProjectOnPlane(desiredMove, hitInfo.normal).normalized;

            m_MoveDir.x = desiredMove.x*speed;
            m_MoveDir.z = desiredMove.z*speed;


            if (m_CharacterController.isGrounded)
            {
                m_MoveDir.y = -m_StickToGroundForce;

                if (m_Jump)
                {
                    m_MoveDir.y = m_JumpSpeed;
                    PlayJumpSound();
                    m_Jump = false;
                    m_Jumping = true;
                }
            }
            else
            {
                m_MoveDir += Physics.gravity*m_GravityMultiplier*Time.fixedDeltaTime;
            }
            m_CollisionFlags = m_CharacterController.Move(m_MoveDir*Time.fixedDeltaTime);

            ProgressStepCycle(speed);
            UpdateCameraPosition(speed);

            m_MouseLook.UpdateCursorLock();
        }


        private void PlayJumpSound()
        {
            m_AudioSource.clip = m_JumpSound;
            m_AudioSource.Play();
        }


        private void ProgressStepCycle(float speed)
        {
            if (m_CharacterController.velocity.sqrMagnitude > 0 && (m_Input.x != 0 || m_Input.y != 0))
            {
                m_StepCycle += (m_CharacterController.velocity.magnitude + (speed*(m_IsWalking ? 1f : m_RunstepLenghten)))*
                             Time.fixedDeltaTime;
            }

            if (!(m_StepCycle > m_NextStep))
            {
                return;
            }

            m_NextStep = m_StepCycle + m_StepInterval;

            PlayFootStepAudio();
        }


        private void PlayFootStepAudio()
        {
            if (!m_CharacterController.isGrounded)
            {
                return;
            }
            // pick & play a random footstep sound from the array,
            // excluding sound at index 0
            int n = Random.Range(1, m_FootstepSounds.Length);
            m_AudioSource.clip = m_FootstepSounds[n];
            m_AudioSource.PlayOneShot(m_AudioSource.clip);
            // move picked sound to index 0 so it's not picked next time
            m_FootstepSounds[n] = m_FootstepSounds[0];
            m_FootstepSounds[0] = m_AudioSource.clip;
        }


        private void UpdateCameraPosition(float speed)
        {
            Vector3 newCameraPosition;
            if (!m_UseHeadBob)
            {
                return;
            }
            if (m_CharacterController.velocity.magnitude > 0 && m_CharacterController.isGrounded)
            {
                m_Camera.transform.localPosition =
                    m_HeadBob.DoHeadBob(m_CharacterController.velocity.magnitude +
                                      (speed*(m_IsWalking ? 1f : m_RunstepLenghten)));
                newCameraPosition = m_Camera.transform.localPosition;
                newCameraPosition.y = m_Camera.transform.localPosition.y - m_JumpBob.Offset();
            }
            else
            {
                newCameraPosition = m_Camera.transform.localPosition;
                newCameraPosition.y = m_OriginalCameraPosition.y - m_JumpBob.Offset();
            }
            m_Camera.transform.localPosition = newCameraPosition;
        }


        private void GetInput(out float speed)
        {
            // Read input
            float horizontal = CrossPlatformInputManager.GetAxis("Horizontal");
            float vertical = CrossPlatformInputManager.GetAxis("Vertical");

            bool waswalking = m_IsWalking;

#if !MOBILE_INPUT
            // On standalone builds, walk/run speed is modified by a key press.
            // keep track of whether or not the character is walking or running
            m_IsWalking = !Input.GetKey(KeyCode.LeftShift);
#endif
            // set the desired speed to be walking or running
            speed = m_IsWalking ? m_WalkSpeed : m_RunSpeed;
            // Handle dynamic setting of whether the character can sprint or not
            speed = m_CanSprint ? speed : m_WalkSpeed;
            m_IsWalking = m_CanSprint ? m_IsWalking : true;
            m_Input = new Vector2(horizontal, vertical);

            // normalize input if it exceeds 1 in combined length:
            if (m_Input.sqrMagnitude > 1)
            {
                m_Input.Normalize();
            }

            // handle speed change to give an fov kick
            // only if the player is going to a run, is running and the fovkick is to be used
            if (m_IsWalking != waswalking && m_UseFovKick && m_CharacterController.velocity.sqrMagnitude > 0)
            {
                StopAllCoroutines();
                StartCoroutine(!m_IsWalking ? m_FovKick.FOVKickUp() : m_FovKick.FOVKickDown());
            }
        }


        private void RotateView()
        {
            m_MouseLook.LookRotation (transform, m_Camera.transform);
        }


        private void OnControllerColliderHit(ControllerColliderHit hit)
        {
            Rigidbody body = hit.collider.attachedRigidbody;
            //dont move the rigidbody if the character is on top of it
            if (m_CollisionFlags == CollisionFlags.Below)
            {
                return;
            }

            if (body == null || body.isKinematic)
            {
                return;
            }
            body.AddForceAtPosition(m_CharacterController.velocity*0.1f, hit.point, ForceMode.Impulse);
        }
    }
}

PlayerGUI.js

#pragma strict

import System.Collections.Generic;

var size : Vector2 = new Vector2(240, 40);

var barX : int = 20;
var barY : int = 20;
var barSpacing : int = 40;

var healthDrainRate : int = 150;
var hungerDrainRate : int = 150;
var thirstDrainRate : int = 100;
var staminaDrainRate : int = 35;

class Player
{
    var health : Stat;
    var hunger : Stat;
    var thirst : Stat;
    var stamina : Stat;
    var stats : List.<Stat>;
    function Player(healthDrainRate : int, hungerDrainRate : int, thirstDrainRate : int, staminaDrainRate : int)
    {
        this.stats = new List.<Stat>();
        this.health = this.CreateStat(healthDrainRate);
        this.hunger = this.CreateStat(hungerDrainRate);
        this.thirst = this.CreateStat(thirstDrainRate);
        this.stamina = this.CreateStat(staminaDrainRate);
    }
    function CreateStat(drainRate : int)
    {
        var stat = Stat(drainRate);
        this.stats.Add(stat);
        return stat;
    }
}

class Stat
{
    var value : float;
    var drainRate : int;
    var displayBar : Bar;
    function Stat(drainRate : int)
    {
        this.value = 1; this.drainRate = drainRate;
    }
    function Decrease()
    {
        this.Sub(Time.deltaTime / this.drainRate);
    }
    function Increase()
    {
        // recover at half the drain rate
        this.Add(Time.deltaTime / (this.drainRate * 2));
    }
    function Add(v : float)
    {
        this.value += v;
        if (this.value >= 1) 
        {
            this.value = 1;
        }
        this.displayBar.Display = this.value;
    }
    function Sub(v : float)
    {
        this.value -= v;
        if (this.value <= 0)
        {
            this.value = 0;
        }
        this.displayBar.Display = this.value;
    }
}

var player = Player(healthDrainRate, hungerDrainRate, thirstDrainRate, staminaDrainRate);

class Bar
{
    var Pos : Vector2;
    var Display : float;
    var EmptyTexture : Texture2D;
    var FullTexture : Texture2D;
    function Bar(x : int, y : int)
    {
        this.Pos = new Vector2(x, y);
        this.Display = 1;
    }
}

for (var i : int = 0; i < len(player.stats); i++)
{
    var localBarY = barY + barSpacing * i;
    var newBar = Bar(barX, localBarY);
    player.stats[i].displayBar = newBar;
}

private var chMotor : UnityStandardAssets.Characters.FirstPerson.FirstPersonController;
private var controller : CharacterController;

var staminaDrainedWait : float = 0.5; // How long to wait when we drain stamina before it starts recovering
var staminaJumpCost : float = 2; // Multiplier from default drain rate

var recoveringStamina : boolean = false;
var regenEnabled : boolean = true;

function Start()
{
    chMotor = GetComponent(UnityStandardAssets.Characters.FirstPerson.FirstPersonController);
	controller = GetComponent(CharacterController);
}

function OnGUI()
{
    for (var stat in player.stats)
    {
        var bar = stat.displayBar;
        GUI.BeginGroup(new Rect (bar.Pos.x, bar.Pos.y, size.x, size.y));
        GUI.Box(Rect(0,0, size.x, size.y), bar.EmptyTexture);

        GUI.BeginGroup(new Rect (0, 0, size.x * bar.Display, size.y));
        GUI.Box(Rect(0,0, size.x, size.y), bar.FullTexture);

        GUI.EndGroup();
        GUI.EndGroup();

    }
}

function TickHealth()
{
    if (player.hunger.value <= 0)
    {
        player.health.Decrease();
    }
    if (player.thirst.value <= 0)
    {
        player.health.Decrease();
    }
    if (player.health.value <= 0)
    {
        Die();
    }
}

function TickStamina()
{
    if (!chMotor.m_IsWalking)
    {
        player.stamina.Decrease();
    } 
    if (chMotor.m_Jumping)
    {
        player.stamina.Sub((Time.deltaTime / staminaDrainRate) * staminaJumpCost);
    }
    if (!chMotor.m_Jumping && chMotor.m_IsWalking && regenEnabled)
    {
        player.stamina.Increase();
    }

    if (player.stamina.value <= 0 && !recoveringStamina)
    {
        chMotor.m_CanJump = false;
        chMotor.m_CanSprint = false;
        recoveringStamina = true; // We need to be recovering next time we get over 0
    } else if (recoveringStamina)
    {
        regenEnabled = false;
        recoveringStamina = false; // So we don't start a bunch of coroutines
        StartCoroutine(RecoverStamina());
    } else {
        // Defaults
        chMotor.m_CanJump = true;
        chMotor.m_CanSprint = true;
    }
}

function Die()
{

}

function Update()
{
    TickHealth();
    player.hunger.Decrease();
    player.thirst.Decrease();
    TickStamina();
}

function RecoverStamina()
{
    yield WaitForSeconds(staminaDrainedWait);
    chMotor.m_CanJump = true;
    chMotor.m_CanSprint = true;
    regenEnabled = true;
}