Unity5 character interaction script

Posted on June 14, 2015

by jayanam

In the last tutorial we created the monster character with the 3 eyes in Blender, now I import him to our Unity5 game Erwin’s timewarp.

What I would like to show you is the interaction of the main character, the dog Erwin, with the monster and how you can code this with C# in Unity3D.

So we start with two rigged characters dropped into the scene of Unity3D:

Two characters in Unity5

We assign a Character Controller to the monster Herbert and an Animation Controller:

Setup of the monster character Herbert

In the image above you can see that we assigned a Seeker script. This component is from the A* Pathfinding framework we described in this tutorial. We used this framework to let the monster rotate to the direction were the player is located – the monster is following the movement of the player.

To achieve this, we need to derive the script for the monster from the class AIPath of the A* framework, here is the whole Monster-script:

<pre>using UnityEngine;
using System.Collections;
using Assets.ErwinsTimewarp.Scripts;
using Assets.ErwinsTimewarp.Scripts.Characters;

namespace Pathfinding
{
    /// <summary>
    /// This class is used to implement the interaction between the monster "Herbert"
    /// and the main character "Erwin" (dog).
    ///
    /// The following used types are written by jayanam and not part of Unity5:
    ///
    /// PlayerController: Class to control the player Erwin (Singleton)
    /// ActionManager: Class with elper e.g. opening the communication panel to
    ///                show a character talking to another
    /// </summary>
    [RequireComponent(typeof(Seeker))]
    public class Monster : AIPath
    {
        private Animator _animator = null;

        public float sleepVelocity = 0.4F;

        protected override void Awake()
        {
            base.Awake();

            _animator = GetComponent<Animator>();
        }

        public override Vector3 GetFeetPosition()
        {
            return tr.position;
        }

        // Use this for initialization
        protected override void Start()
        {
            base.Start();

            target = PlayerController.Instance.PlayerTransform;
        }

        // Update is called once per frame
        protected new void Update()
        {
            if (GameManager.Instance.IsDead)
                return;

            //Get velocity in world-space
            Vector3 velocity;
            if (target != null)
            {
                // Calculate desired velocity
                Vector3 dir = CalculateVelocity(GetFeetPosition());

                // Rotate towards targetDirection (filled in by CalculateVelocity)
                RotateTowards(targetDirection);

                dir.y = 0.0f;

                float dist = Vector3.Distance(PlayerController.Instance.transform.position, tr.position);

                // We are near the monster => monster introduces himself
                if (dist < 3.0f)
                {
                    // Here you can add you own interactions...
                    ActionManager.Instance.OpenTalkPanel(GameManager.Instance.Herbert,
                        "Hi I am Herbert! Are you a friend?");
                }
            }
            else
            {
                velocity = Vector3.zero;
            }
        }
    }
}

And this script also contains the interaction logic: When the dog (Erwin) is near the Herbert (distance < 3.0f), Herbert talks to him. He tells him that his name is Herbert and he asks Erwin if he is a friend.

Interaction sequence of Erwin and Herbert

The class to show the communication panel in the lower screen area is not a part of Unity, we have written it by ourselves. Basically it sets the visible-property of a Unity UI panel to true for a period of 3 seconds, that’s all. But you can add your own interaction code there, it is just an example.

We plan to add a feature that Erwin can have a conversation with other characters for such parts of the game.

The animation controller is very simple: Herbert is doing an Idle animation in which his eyes are moving and he is breathing, therefore there is only one animaton in the controller, the Idle animation: