Hoe maak je een slangenspel in Unity
In dit bericht laat ik zien hoe je een klassiek Snake Game maakt in Unity.
Unity versie gebruikt in deze tutorial: Unity 2018.3.0f2 (64-bit)
Stap 1: Maak het script
Omdat ik een "One Script Game" ben, heb ik voor deze tutorial maar één script nodig:
SC_SnakeGameGenerator.cs
//You are free to use this script in Free or Commercial projects
//sharpcoderblog.com @2019
using System.Collections.Generic;
using UnityEngine;
public class SC_SnakeGameGenerator : MonoBehaviour
{
//Game area resolution, the higher number means more blocks
public int areaResolution = 22;
//Snake movement speed
public float snakeSpeed = 10f;
//Main Camera
public Camera mainCamera;
//Materials
public Material groundMaterial;
public Material snakeMaterial;
public Material headMaterial;
public Material fruitMaterial;
//Grid system
Renderer[] gameBlocks;
//Snake coordenates
List<int> snakeCoordinates = new List<int>();
enum Direction { Up, Down, Left, Right };
Direction snakeDirection = Direction.Right;
float timeTmp = 0;
//Block where the fruit is placed
int fruitBlockIndex = -1;
//Total accumulated points
int totalPoints = 0;
//Game status
bool gameStarted = false;
bool gameOver = false;
//Camera scaling
Bounds targetBounds;
//Text styling
GUIStyle mainStyle = new GUIStyle();
// Start is called before the first frame update
void Start()
{
//Generate play area
gameBlocks = new Renderer[areaResolution * areaResolution];
for (int x = 0; x < areaResolution; x++)
{
for (int y = 0; y < areaResolution; y++)
{
GameObject quadPrimitive = GameObject.CreatePrimitive(PrimitiveType.Quad);
quadPrimitive.transform.position = new Vector3(x, 0, y);
Destroy(quadPrimitive.GetComponent<Collider>());
quadPrimitive.transform.localEulerAngles = new Vector3(90, 0, 0);
quadPrimitive.transform.SetParent(transform);
gameBlocks[(x * areaResolution) + y] = quadPrimitive.GetComponent<Renderer>();
targetBounds.Encapsulate(gameBlocks[(x * areaResolution) + y].bounds);
}
}
//Scale the MainCamera to fit the game blocks
mainCamera.transform.eulerAngles = new Vector3(90, 0, 0);
mainCamera.orthographic = true;
float screenRatio = (float)Screen.width / (float)Screen.height;
float targetRatio = targetBounds.size.x / targetBounds.size.y;
if (screenRatio >= targetRatio)
{
mainCamera.orthographicSize = targetBounds.size.y / 2;
}
else
{
float differenceInSize = targetRatio / screenRatio;
mainCamera.orthographicSize = targetBounds.size.y / 2 * differenceInSize;
}
mainCamera.transform.position = new Vector3(targetBounds.center.x, targetBounds.center.y + 1, targetBounds.center.z);
//Generate the Snake with 3 blocks
InitializeSnake();
ApplyMaterials();
mainStyle.fontSize = 24;
mainStyle.alignment = TextAnchor.MiddleCenter;
mainStyle.normal.textColor = Color.white;
}
void InitializeSnake()
{
snakeCoordinates.Clear();
int firstlock = Random.Range(0, areaResolution - 1) + (areaResolution * 3);
snakeCoordinates.Add(firstlock);
snakeCoordinates.Add(firstlock - areaResolution);
snakeCoordinates.Add(firstlock - (areaResolution * 2));
gameBlocks[snakeCoordinates[0]].transform.localEulerAngles = new Vector3(90, 90, 0);
fruitBlockIndex = -1;
timeTmp = 1;
snakeDirection = Direction.Right;
totalPoints = 0;
}
// Update is called once per frame
void Update()
{
if (!gameStarted)
{
if (Input.anyKeyDown)
{
gameStarted = true;
}
return;
}
if (gameOver)
{
//Flicker the snake blocks
if (timeTmp < 0.44f)
{
timeTmp += Time.deltaTime;
}
else
{
timeTmp = 0;
for (int i = 0; i < snakeCoordinates.Count; i++)
{
if (gameBlocks[snakeCoordinates[i]].sharedMaterial == groundMaterial)
{
gameBlocks[snakeCoordinates[i]].sharedMaterial = (i == 0 ? headMaterial : snakeMaterial);
}
else
{
gameBlocks[snakeCoordinates[i]].sharedMaterial = groundMaterial;
}
}
}
if (Input.GetKeyDown(KeyCode.Space))
{
InitializeSnake();
ApplyMaterials();
gameOver = false;
gameStarted = false;
}
}
else
{
if (timeTmp < 1)
{
timeTmp += Time.deltaTime * snakeSpeed;
}
else
{
timeTmp = 0;
if (snakeDirection == Direction.Right || snakeDirection == Direction.Left)
{
//Detect if the Snake hit the sides
if (snakeDirection == Direction.Left && snakeCoordinates[0] < areaResolution)
{
gameOver = true;
return;
}
else if (snakeDirection == Direction.Right && snakeCoordinates[0] >= (gameBlocks.Length - areaResolution))
{
gameOver = true;
return;
}
int newCoordinate = snakeCoordinates[0] + (snakeDirection == Direction.Left ? -areaResolution : areaResolution);
//Snake has ran into itself, game over
if (snakeCoordinates.Contains(newCoordinate))
{
gameOver = true;
return;
}
if (newCoordinate < gameBlocks.Length)
{
for (int i = snakeCoordinates.Count - 1; i > 0; i--)
{
snakeCoordinates[i] = snakeCoordinates[i - 1];
}
snakeCoordinates[0] = newCoordinate;
gameBlocks[snakeCoordinates[0]].transform.localEulerAngles = new Vector3(90, (snakeDirection == Direction.Left ? -90 : 90), 0);
}
}
else if (snakeDirection == Direction.Up || snakeDirection == Direction.Down)
{
//Detect if snake hits the top or bottom
if (snakeDirection == Direction.Up && (snakeCoordinates[0] + 1) % areaResolution == 0)
{
gameOver = true;
return;
}
else if (snakeDirection == Direction.Down && (snakeCoordinates[0] + 1) % areaResolution == 1)
{
gameOver = true;
return;
}
int newCoordinate = snakeCoordinates[0] + (snakeDirection == Direction.Down ? -1 : 1);
//Snake has ran into itself, game over
if (snakeCoordinates.Contains(newCoordinate))
{
gameOver = true;
return;
}
if (newCoordinate < gameBlocks.Length)
{
for (int i = snakeCoordinates.Count - 1; i > 0; i--)
{
snakeCoordinates[i] = snakeCoordinates[i - 1];
}
snakeCoordinates[0] = newCoordinate;
gameBlocks[snakeCoordinates[0]].transform.localEulerAngles = new Vector3(90, (snakeDirection == Direction.Down ? 180 : 0), 0);
}
}
ApplyMaterials();
}
if (Input.GetKeyDown(KeyCode.RightArrow))
{
int newCoordinate = snakeCoordinates[0] + areaResolution;
if (!ContainsCoordinate(newCoordinate))
{
snakeDirection = Direction.Right;
}
}
if (Input.GetKeyDown(KeyCode.LeftArrow))
{
int newCoordinate = snakeCoordinates[0] - areaResolution;
if (!ContainsCoordinate(newCoordinate))
{
snakeDirection = Direction.Left;
}
}
if (Input.GetKeyDown(KeyCode.UpArrow))
{
int newCoordinate = snakeCoordinates[0] + 1;
if (!ContainsCoordinate(newCoordinate))
{
snakeDirection = Direction.Up;
}
}
if (Input.GetKeyDown(KeyCode.DownArrow))
{
int newCoordinate = snakeCoordinates[0] - 1;
if (!ContainsCoordinate(newCoordinate))
{
snakeDirection = Direction.Down;
}
}
}
if (fruitBlockIndex < 0)
{
//Place a fruit block
int indexTmp = Random.Range(0, gameBlocks.Length - 1);
//Check if the block is not occupied with a snake block
for (int i = 0; i < snakeCoordinates.Count; i++)
{
if (snakeCoordinates[i] == indexTmp)
{
indexTmp = -1;
break;
}
}
fruitBlockIndex = indexTmp;
}
}
void ApplyMaterials()
{
//Apply Snake material
for (int i = 0; i < gameBlocks.Length; i++)
{
gameBlocks[i].sharedMaterial = groundMaterial;
bool fruitPicked = false;
for (int a = 0; a < snakeCoordinates.Count; a++)
{
if (snakeCoordinates[a] == i)
{
gameBlocks[i].sharedMaterial = (a == 0 ? headMaterial : snakeMaterial);
}
if (snakeCoordinates[a] == fruitBlockIndex)
{
//Pick a fruit
fruitPicked = true;
}
}
if (fruitPicked)
{
fruitBlockIndex = -1;
//Add new block
int snakeBlockRotationY = (int)gameBlocks[snakeCoordinates[snakeCoordinates.Count - 1]].transform.localEulerAngles.y;
//print(snakeBlockRotationY);
if (snakeBlockRotationY == 270)
{
snakeCoordinates.Add(snakeCoordinates[snakeCoordinates.Count - 1] + areaResolution);
}
else if (snakeBlockRotationY == 90)
{
snakeCoordinates.Add(snakeCoordinates[snakeCoordinates.Count - 1] - areaResolution);
}
else if (snakeBlockRotationY == 0)
{
snakeCoordinates.Add(snakeCoordinates[snakeCoordinates.Count - 1] + 1);
}
else if (snakeBlockRotationY == 180)
{
snakeCoordinates.Add(snakeCoordinates[snakeCoordinates.Count - 1] - 1);
}
totalPoints++;
}
if (i == fruitBlockIndex)
{
gameBlocks[i].sharedMaterial = fruitMaterial;
gameBlocks[i].transform.localEulerAngles = new Vector3(90, 0, 0);
}
}
}
bool ContainsCoordinate(int coordinate)
{
for (int i = 0; i < snakeCoordinates.Count; i++)
{
if (snakeCoordinates[i] == coordinate)
{
return true;
}
}
return false;
}
void OnGUI()
{
//Display Player score and other info
if (gameStarted)
{
GUI.Label(new Rect(Screen.width / 2 - 100, 5, 200, 20), totalPoints.ToString(), mainStyle);
}
else
{
GUI.Label(new Rect(Screen.width / 2 - 100, Screen.height / 2 - 10, 200, 20), "Press Any Key to Play\n(Use Arrows to Change Direction)", mainStyle);
}
if (gameOver)
{
GUI.Label(new Rect(Screen.width / 2 - 100, Screen.height / 2 - 20, 200, 40), "Game Over\n(Press 'Space' to Restart)", mainStyle);
}
}
}Het script hierboven creëert een raster van primitieve quads en verandert vervolgens hun materialen in een van de vier: een achtergrondmateriaal, een slangkopmateriaal, een slanglichaammateriaal of een appelmateriaal. Het plaatst de camera ook automatisch direct boven het rastersysteem en verandert de orthografische grootte om de collectieve grenzen van alle blokken in te kapselen.
Stap 2: Het slangenspel opzetten
Laten we nu het Snake-spel opzetten met behulp van het bovenstaande script:
- Nieuwe scène maken
- Wijzig de resolutie van de gameweergave zodat de breedte en hoogte gelijk zijn (bijv. 600px x 600px)
- Maak een nieuw GameObject (GameObject -> Create Empty) en geef het de naam "_GameGenerator"
- Voeg het SC_SnakeGameGenerator.cs-script toe aan het _GameGenerator-object
Zoals u zult merken, heeft SC_SnakeGameGenerator een aantal variabelen die toegewezen moeten worden:
- De variabele Hoofdcamera spreekt voor zich: wijs de standaard hoofdcamera toe.
- Voor de materialen, maak 4 materialen (rechtermuisklik -> Maken -> Materiaal) en noem ze respectievelijk "ground_material", "snake_material", "head_material" en "fruit_material":
Voor de ground_material wijzigt u de shader naar Unlit/Color en wijzigt u de hoofdkleur naar zwart:
Voor de andere 3 Materialen wijzigt u de Shader naar Onverlicht/Textuur en wijst u de onderstaande Texturen toe:
Voor snake_material:
Voor head_material:
Voor fruit_material:
- Wijs de materialen toe aan variabelen
Nu is het tijd om op Play te drukken en het spel te testen:
Alles werkt zoals verwacht, nu heb je een speelbaar slangenspel in Unity.