First Encounter with a Small Demo Made in Unity
-
Setting Up the Spaceship and Scene
Scene Layout: Place the lights in appropriate positions, pull the camera above the lights, create a new quad in the scene as a background, apply a material texture to it, drag the spaceship player into the scene, adjust its position, and add a fire effect at the tail of the spaceship. -
Writing a Flight Script for the Spaceship
Player.cs:
public float speed = 5.0f;
float moveH = Input.GetAxis("Horizontal");
float moveV = Input.GetAxis("Vertical");
Vector3 move = new Vector3(moveH, 0, moveV);
transform.Translate(speed * move * Time.deltaTime);
Drag the player.cs script onto the spaceship in Unity, making it a child object of the spaceship, so that the spaceship can be controlled with the up, down, left, and right keys on the keyboard.
- Creating Bullet Flight and Prefab
Create a new game empty in the hierarchy named bolt, create a new quad as a child object of bolt, apply a material to it, adjust the bullet model's position below the spaceship, and create a flight script bolt_move.cs for the bullet:
public float speed = 5.0f;
// Fly in the positive direction along the z-axis
// Update is called once per frame
void Update () {
transform.Translate(Vector3.forward * speed * Time.deltaTime);
}
Similarly, drag the script onto the bullet, add a rigidbody component and a capsule collider to the bullet:
Create a prefab for the bullet and place it in _prefab:
Just drag the bolt from the hierarchy to _prefab in the assets.
- Bullet Firing
Create a bullet firing script and place it in the player:
// Time interval
public float fireRate = 0.5f;
// Fire a bullet every 0.5f
public float nextFire = 0.0f;
public GameObject shot;
public Transform shotSpawn;
// Click the mouse to fire a bullet
if (Input.GetButton("Fire1") && Time.time > nextFire)
{
// A series of bullets with issues appeared, need to control the firing of bullets with time
nextFire = Time.time + fireRate;
// Instantiate (instantiate object 'position' angle)
Instantiate(shot, shotSpawn.position, shotSpawn.rotation);
}
Click on the player and complete the settings in the inspector:
Run it, and the bullets will fire from below the airplane.
- Bullet Destruction and Collision Detection
Create a new cube named boundary, adjust its size and position to surround the spaceship.
Create a bullet destruction script destbyboundary.cs:
void OnTriggerExit(Collider other)
{
Destroy(other.gameObject);
}
Drag it into the boundary:
The relevant settings are as follows.
Run it, and the bullets will be destroyed when they fly out of the boundary.
- Adding Meteor Movement and Destruction
Create a new game object named Asterial, drag a meteor model as a child object, adjust its position in the scene, and create a movement script as_move.cs for it:
public float speed = 5.0f;
void Update () {
transform.Translate(Vector3.back * speed * Time.deltaTime);
}
Add a rigidbody component and a capsule collider to it.
Also, create a prefab for it, which will appear automatically later.
- Adding Tag
Add the following code to the as_move.cs script:
// Asteroid rigidbody and collider trigger, boundary has a collider trigger, it will naturally respond when the trigger enters.
void OnTriggerEnter(Collider other)
{
//print(other.name);// The corresponding name is boundary, destruction is boundary, so it needs to be modified
// Instantiate particle object
if (other.tag == "Boundary")
return;
gameController.GameOver();
Destroy(other.gameObject);
}
Make property response modifications here.
- Explosion of Meteor and Spaceship
Add the following code to as_move.cs:
public GameObject explosion;
public GameObject playerExplosion;
// Instantiate the explosion particle effect of the asteroid, generate particle effects at the position of the asteroid
Instantiate(explosion, transform.position, transform.rotation);
// Instantiate the explosion effect of the player, which is the spaceship, generate particle effects at the position of the spaceship
if (other.tag == "Player")
{
Instantiate(playerExplosion, other.transform.position, other.transform.rotation);
}
Destroy(other.gameObject);
// After the asteroid is hit, the player's score increases, and this process needs to be notified to the Text control for display
gameController.AddScore(scoreValue);
Destroy(gameObject);
}
Set as shown in the figure.
After running, the shooting meteor and explosion effects after collision will appear.
- Batch Generation of Meteors:
Here we need to use a coroutine method:
IEnumerator WaitAndPrint()
{
yield return new WaitForSeconds(5);
print("WaitAndPrint" + Time.time);
}
Create a new game object named gamecontroller, and create a script gamecontroller.cs:
// Instantiate the asteroid object, position
public GameObject hazard; // Represents the asteroid object
public Vector3 spawnValues; // Represents the change values of the x-axis and z-axis for generation
private Vector3 spawnPosition = Vector3.zero; // Represents the generation position
private Quaternion spawnRotation;
public int hazardCount = 6;
// Delay generation time
public float spawnWait;
// Do not want the game to generate asteroids immediately at the beginning, but wait for a while, add a variable to control the waiting time
public float startWait = 1.0f;
// Code to generate asteroids
IEnumerator SpawnWaves()
{
yield return new WaitForSeconds(startWait);
while (true)
{
for (int i = 0; i < hazardCount; i++)
{
spawnPosition.x = Random.Range(-spawnValues.x, spawnValues.x);
spawnPosition.z = spawnValues.z;
spawnRotation = Quaternion.identity;
Instantiate(hazard, spawnPosition, spawnRotation);
yield return new WaitForSeconds(spawnWait);
}
yield return new WaitForSeconds(2.0f);
}
}
void Start () {
StartCoroutine(SpawnWaves());
}
Set the required parameters according to the scene.
Run it, and the meteors can be generated randomly.
- Creating a Data Transfer Between Different Scripts, Creating a Game Lifecycle: Record Scores, Game Over, and Restart
Add the following code to as_move.cs:
private GameController gameController;
public int scoreValue; // Increased score
gameController.GameOver();
void Start()
{
// Bind the gamecontroller defined here with the previous gamecontroller, generally speaking
// So we first find the object with findwithtag, and then use getcomponent to find the gamecontroller script
GameObject go = GameObject.FindWithTag("GameController"); // Note, must modify in property response
if (go != null)
gameController = go.GetComponent<GameController>();
else
Debug.Log("Cannot find the object with tag GameController");
if (gameController == null)
Debug.Log("Cannot find the script GameController.cs");
}
Add the following code to gamecontroller.cs:
public Text ScoreText;
private int score;
public Text gameOverText;
private bool gameOver;
public Text restartText;
private bool restart;
if (gameOver)
{
restartText.text = "Press [R] to Restart";
restart = true;
break;
}
}
// Use this for initialization
void Start () {
score = 0;
ScoreText.text = "Score: " + score;
gameOverText.text = "";
gameOver = false;
restartText.text = "";
restart = false;
StartCoroutine(SpawnWaves());
}
// Modify score
public void AddScore(int newScoreValue)
{
score += newScoreValue;
ScoreText.text = "Score: " + score;
}
// Modify end properties
public void GameOver()
{
gameOver = true;
gameOverText.text = "Game Over";
}
void Update()
{
if (restart)
{
if (Input.GetKeyDown(KeyCode.R))
Application.LoadLevel(Application.loadedLevel);
}
}
Set up the scene as follows:
Thus, a small space spaceship game is basically completed.
Run the game:
