Power..Power..Power

What is a Power up?

Power-ups are interesting and useful components to make a game more interesting.

In this Article you will learn how to:

  • create PowerUp system
  • create a simple game demo with PowerUps

NOTE : You must have knowledge of basic Unity concepts and c# language. If you are fresher in Game Development then study this tutorial _____link____

PowerUp Demo in Unity

Create a new Unity Project

Unity Hub

Import 3D Environment & Character

Click here -> https://assetstore.unity.com/packages/3d/environments/urban/toon-gas-station-155369

3D Asset
Character of Mixamo Website
  • Download Idle, Walk, and Run Animation Clips.
Character with animation downloading
  • Import the character In Unity.
All animation clips
  • Right-click on the character file.
  • Extract Material and Texture file from the Character Model.
Extract material and texture from Character Object
  • Drag the character object from the Project Window to the Scene Window.
Drag the object from the project window to the hierarchy window
  • Rename the character to “Joe”.
Character Rig Menu
  • In the project window, right-click on the player and go to the settings.
  • Select “Create From This Model” option in avatar Definition.
  • Select the Root node from the list.
Create an avatar of the character object
  • So you will get a character avatar as below.
  • An avatar is very useful in applying animation to the character model.
Avatar in Character Model
Add Rigidbody and Capsule Collider
  • Add an Animator Component to the Character Object.
  • There is no Animator controller available in Animator. So you have to build a new one.
  • For that, go to the project window, right-click & create Animator Controller.
Animation Controller
  • Assign the animator controller to the Animator Component.
Assign the animator controller and Avatar
  • Go to Window > Animation >Animator > Open the Animator Window.
  • Create a parameter in Animator Window -> isWalking Bool.
  • Add three animation clips in this Animator controller.
    • Idle
    • Walking
    • PowerUp
  • Assign transition arrow to each animation clips.
Animator Window
  • Idle to Walking Transition
  • Walking to Idle Transition
  • PowerUp to Idle Transition
  • Drag the character from the Hierarchy Window to Project Window so it will create a Prefab of the current character object.
Character Prefab

PowerUp Object setup

Now you have to add some PowerUps in the Game.

  • Import the capsule object in the current project.
Capsule model and texture files
  • Create a material for Capsule Object.
create a new material for Capsule
  • Create an Empty GameObject in the Hierarchy window and rename it to “PowerUp1”.
  • Add a particle system as a child of “PowerUp1”.
Steps of Particle system
  • Change the partical system settings as below.
PowerUp1 Particle System
  • Here, in Render Mode -> select Mesh
  • Render Mesh -> pill_C_001_geo
Capsule Mesh
  • Duplicate the PowerUp1 Object and rename duplicated object as “PowerUp2”.
  • In PowerUp2, all are same, just replace Render Mesh – pii_C_002_geo
  • so you will get 2 powerUp Capsules
Power Up Capsules
  • In-Game, when the player touches the capsule, the player will get power and becomes bigger.
  • So you have to add a box collider in both PowerUp Objects.
  • Turn the isTrigger property on the box collider component of PowerUps.
  • Create a new c# script with the name “PowerUpScript.”
  • Assign this script to both PowerUps Objects.

PowerUpScript

C#
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
 
public class PowerUpScript : MonoBehaviour
{
    //this variable with store PowerUp number
    public int powerNumber;
 
    void OnTriggerEnter(Collider other)
    {
        //if any object with Player tag collide with this object when
        if (other.CompareTag("Player"))
        {
            PlayerMovementController.instance.PowerUpActionCalled(powerNumber);
            Destroy(gameObject);
        }
    }
}

Here,

  • When character joe (tag player) will collide with this power-up object at that time this script will execute.
  • It will be called the method of another script and pass the power number in it.

PlayerMovementController Script

  • Create a new c# script for Player Movement and Power Up Actions.
  • Rename this script to the “PlayerMovementController.”
  • Assign the PlayerMovementController script to our Joe Character.
C#
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
using System.Collections;
using System.Collections.Generic;
using UnityEditor;
using UnityEngine;
using UnityEngine.UI;
 
public class PlayerMovementController : MonoBehaviour
{
    public static PlayerMovementController instance;
 
    //Animation Objects
    public Animator playerAnimator;
 
    //character object
    public GameObject playerModel;
 
    //bool variables
    public bool isPowerUpAnimation;
    public bool isPower1Up;
    public bool isPower2Up;
 
    //float variables
    public float moveSpeed;
    public float power1Timer;
    public float power2Timer;
    public float currentPowerId;
 
    //UI Objhects
    public GameObject Power1Box;
    public GameObject Power2Box;
    public Image power1_bar;
    public Image power2_bar;
 
 
    private void Start()
    {
        instance = this;
        Power1Box.SetActive(false);
        Power2Box.SetActive(false);
    }
 
    // Update is called once per frame
    void FixedUpdate()
    {
        //If PowerUp Animation is running then the player must stop moving
        if (!isPowerUpAnimation)
        {
            //get Player movement and direction using Input system.
            Vector3 moveDir = new Vector3(Input.GetAxis("Horizontal"), 0, Input.GetAxis("Vertical"));
 
            //Player will move according to time and speed
            playerModel.transform.position += Time.deltaTime * moveSpeed * moveDir;
 
            //Player will look towards the direction that we want to allow  
            playerModel.transform.rotation = Quaternion.LookRotation(moveDir);
 
            if (moveDir.x != 0 || moveDir.z != 0)
            {
                playerAnimator.SetBool("isWalk", true);
            }
            else
            {
                playerAnimator.SetBool("isWalk", false);
            }
        }
 
        //If PowerUp-1 is On then PowerUP-1's Timer bar will start descreasing
        if (isPower1Up)
        {
            power1_bar.fillAmount -= Time.deltaTime / power1Timer;
        }
 
        //If PowerUp-2 is On then PowerUP-2's Timer bar will start descreasing
        if (isPower2Up)
        {
            power2_bar.fillAmount -= Time.deltaTime / power2Timer;
        }
 
        //When Power1up is Over - PowerUp-1's Effect will stop
        if (power1_bar.fillAmount == 0)
        {
            Debug.Log("Scale Down");
            isPower1Up = false;
            Power1Box.SetActive(false);
            power1_bar.fillAmount = 1;
            //Effect
            gameObject.transform.localScale = new Vector3(1.5f, 1.5f, 1.5f);
 
            if(!isPower2Up)
            {
                playerAnimator.speed = 1;
                moveSpeed = 2;
            }
        }
 
        //When Power2up is Over - PowerUp-2's Effect will stop
        if (power2_bar.fillAmount==0)
        {
            Debug.Log("Speed Down");
            isPower2Up = false;
            Power2Box.SetActive(false);
            power2_bar.fillAmount = 1;
            //Effects
            playerAnimator.speed = 1;
            moveSpeed = 2;
        }
    }
 
    //When the Player collides with the PowerUp Capsule this method will be called
    public void PowerUpActionCalled(int powerId)
    {
        currentPowerId = powerId;
        StartCoroutine(WaitForPowerUpAnimation());
    }
 
    //for Power up animation
    IEnumerator WaitForPowerUpAnimation()
    {
        //PowerUp animation start
        isPowerUpAnimation = true;
        playerAnimator.Play("PowerUp");
        playerAnimator.SetBool("isWalking", false);
        yield return new WaitForSeconds(2);
 
        //PowerUp animation over
        //playerAnimator.SetBool("isWalking", true);
        isPowerUpAnimation = false;
 
        //if powerUp-1 is active then the players scale increases
        if (currentPowerId == 1)
        {
            isPower1Up = true;
            Power1Box.SetActive(true);
            power1_bar.fillAmount = 1;
            Debug.Log("Scale up");
            gameObject.transform.localScale = new Vector3(3, 3, 3);
            moveSpeed = 4;
        }
 
        //if powerUp-2 is active then the players speed increases
        else if (currentPowerId == 2)
        {
            isPower2Up = true;
            Power2Box.SetActive(true);
            power2_bar.fillAmount = 1;
            Debug.Log("Speed Up");
            moveSpeed = 6;
            playerAnimator.speed = 2;
        }
    }
}

Here,

  • When the Player touches the Power Up Capsule Object, at that time the PowerUpActionCalled() method will be called with power id.
  • Then the power number will be stored in CurrentPowerId Variable and one coroutine method call for PowerUp Animation.
  • It will set isPowerUpAnimation boolean variable as true.
  • It will execute a process for 2 seconds to complete PowerUp Animation first.
  • After that, the isPowerUpAnimation boolean variable is set to false because the PowerUpAnimation is over.
  • Now if currentPowerId =1 then isPower1Up boolean will be true so,
    • PowerUP-1 Bar is active
    • isPower1Up bool is true
    • PowerUP-1 Bar value set to full
    • Character scale set to 3
    • Increase Movespeed=4
  • If currentPowerId =2 then
    • PowerUP-2 Bar active
    • isPower2Up bool is true
    • PowerUP-2 Bar value set full
    • Increase Movespeed=8
  • so isPower1Up bool is true, then Power1Up’s Timer starts decreasing from Timer value to 0. Once it reached 0, Power1Up’s Effect will disappear.
  • same condition for Power2Up
  • If the value of power1_bar.fillAmount is zero then
    • isPower1Up is false
    • Deactivate Power1 bar
    • Character scale set to normal
    • power1_bar.fillAmount=1 (otherwise loop iterating continue)

Adding the UI Components

  • Now you have to add two power bars to show power effect timing on the screen.
  • Click on the “+” button and add the UI Canvas object in the Hierarchy window.
  • Add an image on the top left side of the screen in Canvas and rename it to “Power1Box.“
  • Add another image object as a child of Power1Box and rename it to Power1_Bar.
  • Duplicate “Power1Box” and create Power2Box.
PowerUp1 & PowerUp2 timer bar

camera follow Script

C#
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
 
public class CameraFollowController : MonoBehaviour
{
    //The Target Object
    public Transform targetObject;
 
    //Default minimum distance between the target and the player
    public Vector3 cameraOffset;
 
    //Smooth factor will use in Slerping
    public float smoothFactor = 0.5f;
 
 
    // Start is called before the first frame update
    void Start()
    {
        cameraOffset = transform.position - targetObject.transform.position;
    }
 
    // Update is called once per frame
    void LateUpdate()
    {
        //Camera Position Change
        Vector3 newPosition = targetObject.transform.position + cameraOffset;
        transform.position = Vector3.Slerp(transform.position, newPosition, smoothFactor);
    }
}
  • Change the Camera Position and rotation as below.
  • Assign CameraFollowController Script to Camera.
Camera Settings

Final Output

Output

Summary

In This Article, you learned about the Power Up System using it in a simple game.