Basics 4 (Stack of scenes)

#Tutorial navigation

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#Game

The Game class provides methods to manipulate the stack of GameScene.

• Game.change(GameScene scene) This method will make the engine pop the scene in the top of the stack and will push scene.
• Game.push(GameScene scene) This method will make the engine push scene.
• Game.pop(Object... args) This method will make the engine pop the scene in the top of the stack and, if there is any scene remaining, will call the GameScene.wakeup(Object... args) method, passing args as argument.
• Game.quit() This method will make the engine clear the stack, causing the interruption of the main loop.

#Full working code

package mygame.scene;

import org.unbiquitous.uImpala.engine.core.GameComponents;
import org.unbiquitous.uImpala.engine.core.GameScene;
import org.unbiquitous.uImpala.engine.core.Game;

public class MyFirstScene extends GameScene {
  private Game game;
  
  public MyFirstScene() {
    game = GameComponents.get(Game.class);
  }
  
  protected void update() {
    if (false) // if user pressed 'enter'
      game.change(new MyLevelScene());
    if (false) // if user pressed 'o'
      game.push(new MyOptionsScene());
    if (false) // if user pressed 'q'
      game.quit();
  }
  
  protected void render() {
    // TODO
  }
  
  protected void wakeup(Object... args) {
    // TODO
  }
  
  protected void destroy() {
    // TODO
  }
}

package mygame.scene;

import mygame.object.MyPlayer;

import org.unbiquitous.uImpala.engine.core.ContainerScene;

public class MyLevelScene extends ContainerScene {
  public MyLevelScene() {
    add(new MyPlayer(assets));
  }
}

package mygame.object;

import org.unbiquitous.uImpala.engine.asset.AssetManager;
import org.unbiquitous.uImpala.engine.core.GameComponents;
import org.unbiquitous.uImpala.engine.core.GameObject;
import org.unbiquitous.uImpala.engine.core.GameRenderers;
import org.unbiquitous.uImpala.engine.core.Game;

public class MyPlayer extends GameObject {
  public MyPlayer(AssetManager assets) {
    // TODO
  }

  protected void update() {
    if (false) // if user pressed 'q'
      GameComponents.get(Game.class).quit();
  }

  protected void render(GameRenderers renderers) {
    // TODO
  }

  protected void wakeup(Object... args) {
    // TODO
  }

  protected void destroy() {
    // TODO
  }
}

package mygame.scene;

import org.unbiquitous.uImpala.engine.core.GameComponents;
import org.unbiquitous.uImpala.engine.core.GameScene;
import org.unbiquitous.uImpala.engine.core.Game;

public class MyOptionsScene extends GameScene {
  public MyOptionsScene() {
    // TODO
  }
  
  protected void update() {
    if (false) // if user pressed 'esc'
      GameComponents.get(Game.class).pop();
  }
  
  protected void render() {
    // TODO
  }
  
  protected void wakeup(Object... args) {
    // TODO
  }
  
  protected void destroy() {
    // TODO
  }
}

#Tutorial navigation

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• [Next: Basics 5 (Rendering)](Basics 5 (Rendering))