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Member Since 24 Aug 2013
Offline Last Active Feb 03 2015 06:38 AM

Posts I've Made

In Topic: [C++][ALLEGRO5] How to make a Title screen and different screen states?

01 November 2013 - 12:30 AM


A state machine, as fastcall mentioned really is the best way to go, but the psuedo code presented makes it look like a giant switch statement, which I tend to try to avoid. Switches are fast which is good, but it tends to cluster your code together more than I like.


The way I generally do it is very similar to how XNA structures the game class.


I create a base GameStateNode class with Update/Draw functions, then each specific game state implements those functions however they like.

class GameStateNode
   virtual void gameStateNode Update(WorldState worldState)
   virtual void Draw(WorldState worldState)

class TitleScreen:GameStateNode
 void Update(worldState worldState)
     if (KeyPressed(EnterButton))
        worldState.NextState=new MenuState();
 void Draw(WOrldState worldState)

Class MenuState(){....}

void main()
  WorldState world =new WorldState()
  world.CurrentNode=new TitleScreen()

     if (world.NextState!=null)

Interesting.. although I'm trying to avoid using classes right now, need to learn more about them.

In Topic: [C++][ALLEGRO5] How to make a Title screen and different screen states?

31 October 2013 - 12:45 AM


How do I make , for example a Title screen and when an option is selected, for example "Play game", the screen switches to the gameplay screen?
Do I have to clear the screen and then enter the game loop?
Do I need to make Individual loops inside the main gameoop for different screens, if yes, can you provide a quick example?

I still don't understand the screen states.

Read up on state machines, they'll help out here. What you want to do in this case is to use a state machine and transition to and from states. Implementations can be simple or complex, but you should only use one game loop.

Here's a small example: 
set state to 'title screen'
while game is still running:
    handle input
    update according to state:
        when state is 'title screen':
            update timer
            update fade animation
            if timer expired or user pressed skip button:
                set state to menu
        when state is 'menu':
            navigate menu according to user input
            if user pressed 'start game' GUI button:
                set state to 'game'
        when state is 'game':
            if user pressed menu button:
                set state to 'menu'
            update game
    render according to state:
        when state is 'title screen':
            draw splash screen
            draw fade transition

        when state is 'menu':
            draw menu
            draw selected item
        when state is 'game':
            draw game
    present image

Amazing, thanks alot!
Although, essentially it's the same thing I thought of,just cleaner. The functions would be still loops till the user prompts(example, selects "Play game").
But thanks for clearing it up.

In Topic: My first game, a Pong spinoff.

31 August 2013 - 09:37 PM

I didn't build it and run it since I don't have allegro, but I glanced over it real quick.


Just a couple styling questions:


Why are D_WIDTH and D_HEIGHT defines?  It would be better (style wise) to use constants like you did for your FPS variable.

For variables like scor and diflevel, you may want to consider using vectors so you can add more amounts of score? and difficulty with ease.


For the next step in the project I would sort things into classes and more functions instead of having everything in main.  Looks good for a beginner, although I didn't play it and just glanced through it.


I never actually plan things out, Improv all the way, anyways so I defined them first just for fun and when I reached to timer, I initialized FPS, you see, when I finished the project I was like "You know what it needs?, a difficulty" so I just create integers at random places and hope it doesn't mess up.


You see, I just wanted this game to "Work" , the collision is also messed up sometimes, but works.

And, Now i'll take it more seriously and will plan and break the project into modules.

Thanks for the tips! Have a good day.