Keeping entities inside the map

Fixes #13

src/entity/Entity.java

@@ -1,6 +1,7 @@
 package entity;
 
 import assets.Assets;
+import game.Game;
 import org.joml.Matrix4f;
 import org.joml.Vector2f;
 import org.joml.Vector3f;
@@ -52,8 +53,16 @@ public void useAnimation(int index) {
 	}
 
 	public void move(Vector2f direction) {
+	    World world = Game.getInstance().getWorld();
+
 		transform.pos.add(new Vector3f(direction, 0));
-
+
+		transform.pos.x = Math.max(0, transform.pos.x);
+		transform.pos.x = Math.min(transform.pos.x, world.getWidth());
+
+		transform.pos.y = Math.min(0, transform.pos.y);
+		transform.pos.y = Math.max(transform.pos.y, -world.getHeight());
+
 		boundingBox.getCenter().set(transform.pos.x, transform.pos.y);
 	}
 

src/world/World.java

@@ -198,4 +198,7 @@ public int getScale() {
 	}
 
 	public List<Entity> getEntities() {return this.entities;}
+
+	public int getWidth() {return this.width;}
+	public int getHeight() {return this.height;}
 }