I'm making a game designed with the entity-component paradigm that uses systems to communicate between components as explained here. I've reached the point in my development that I need to add game states (such as paused, playing, level start, round start, game over, etc.), but I'm not sure how to do it with my framework. I've looked at this code example on game states which everyone seems to reference, but I don't think it fits with my framework. It seems to have each state handling its own drawing and updating. My framework has a SystemManager that handles all the updating using systems. For example, here's my RenderingSystem class:
public class RenderingSystem extends GameSystem {
private GameView gameView_;
/**
* Constructor
* Creates a new RenderingSystem.
* @param gameManager The game manager. Used to get the game components.
*/
public RenderingSystem(GameManager gameManager) {
super(gameManager);
}
/**
* Method: registerGameView
* Registers gameView into the RenderingSystem.
* @param gameView The game view registered.
*/
public void registerGameView(GameView gameView) {
gameView_ = gameView;
}
/**
* Method: triggerRender
* Adds a repaint call to the event queue for the dirty rectangle.
*/
public void triggerRender() {
Rectangle dirtyRect = new Rectangle();
for (GameObject object : getRenderableObjects()) {
GraphicsComponent graphicsComponent =
object.getComponent(GraphicsComponent.class);
dirtyRect.add(graphicsComponent.getDirtyRect());
}
gameView_.repaint(dirtyRect);
}
/**
* Method: renderGameView
* Renders the game objects onto the game view.
* @param g The graphics object that draws the game objects.
*/
public void renderGameView(Graphics g) {
for (GameObject object : getRenderableObjects()) {
GraphicsComponent graphicsComponent =
object.getComponent(GraphicsComponent.class);
if (!graphicsComponent.isVisible()) continue;
GraphicsComponent.Shape shape = graphicsComponent.getShape();
BoundsComponent boundsComponent =
object.getComponent(BoundsComponent.class);
Rectangle bounds = boundsComponent.getBounds();
g.setColor(graphicsComponent.getColor());
if (shape == GraphicsComponent.Shape.RECTANGULAR) {
g.fill3DRect(bounds.x, bounds.y, bounds.width, bounds.height,
true);
} else if (shape == GraphicsComponent.Shape.CIRCULAR) {
g.fillOval(bounds.x, bounds.y, bounds.width, bounds.height);
}
}
}
/**
* Method: getRenderableObjects
* @return The renderable game objects.
*/
private HashSet<GameObject> getRenderableObjects() {
return gameManager.getGameObjectManager().getRelevantObjects(
getClass());
}
}
Also all the updating in my game is event-driven. I don't have a loop like theirs that simply updates everything at the same time.
I like my framework because it makes it easy to add new GameObjects, but doesn't have the problems some component-based designs encounter when communicating between components. I would hate to chuck it just to get pause to work. Is there a way I can add game states to my game without removing the entity-component design? Does the game state example actually fit my framework, and I'm just missing something?
