• Announcements

    • khawk

      Download the Game Design and Indie Game Marketing Freebook   07/19/17

      GameDev.net and CRC Press have teamed up to bring a free ebook of content curated from top titles published by CRC Press. The freebook, Practices of Game Design & Indie Game Marketing, includes chapters from The Art of Game Design: A Book of Lenses, A Practical Guide to Indie Game Marketing, and An Architectural Approach to Level Design. The GameDev.net FreeBook is relevant to game designers, developers, and those interested in learning more about the challenges in game development. We know game development can be a tough discipline and business, so we picked several chapters from CRC Press titles that we thought would be of interest to you, the GameDev.net audience, in your journey to design, develop, and market your next game. The free ebook is available through CRC Press by clicking here. The Curated Books The Art of Game Design: A Book of Lenses, Second Edition, by Jesse Schell Presents 100+ sets of questions, or different lenses, for viewing a game’s design, encompassing diverse fields such as psychology, architecture, music, film, software engineering, theme park design, mathematics, anthropology, and more. Written by one of the world's top game designers, this book describes the deepest and most fundamental principles of game design, demonstrating how tactics used in board, card, and athletic games also work in video games. It provides practical instruction on creating world-class games that will be played again and again. View it here. A Practical Guide to Indie Game Marketing, by Joel Dreskin Marketing is an essential but too frequently overlooked or minimized component of the release plan for indie games. A Practical Guide to Indie Game Marketing provides you with the tools needed to build visibility and sell your indie games. With special focus on those developers with small budgets and limited staff and resources, this book is packed with tangible recommendations and techniques that you can put to use immediately. As a seasoned professional of the indie game arena, author Joel Dreskin gives you insight into practical, real-world experiences of marketing numerous successful games and also provides stories of the failures. View it here. An Architectural Approach to Level Design This is one of the first books to integrate architectural and spatial design theory with the field of level design. The book presents architectural techniques and theories for level designers to use in their own work. It connects architecture and level design in different ways that address the practical elements of how designers construct space and the experiential elements of how and why humans interact with this space. Throughout the text, readers learn skills for spatial layout, evoking emotion through gamespaces, and creating better levels through architectural theory. View it here. Learn more and download the ebook by clicking here. Did you know? GameDev.net and CRC Press also recently teamed up to bring GDNet+ Members up to a 20% discount on all CRC Press books. Learn more about this and other benefits here.
Sign in to follow this  
Followers 0
SonicD007

Passing information between gamestates

7 posts in this topic

Hi,  I'm using the gamestate sample from: http://gamedevgeek.com/tutorials/managing-game-states-in-c/  and I want to pass information from one gamestate to another gamestate.  In particular, I'm thinking of creating a LogIn state in which it will connect to a server, verify/login, then grab the character data.  I then want to pass the character data to the next gamestate (PlayGameState or something) and use that data to do whatever game logic I need done.  What would be the best way to do this?  Would I need to change the Init class to have another parameter in which I can pass a generic object of some sort similar to how C# forms use the Tag property to exchange data with other forms?  How would you do this?

0

Share this post


Link to post
Share on other sites

I would pass the data as a structure parameter in the state's Instance function. If you design your game well, you should not need to pass a lot of structures between states. If you were to successfully login, it could pass the character data to a loading screen state. The data could contain information on where the character was last in the game, and based on that information, load that part of the world for the game for the state following the loading screen.

Also consider what data you want to be persistent throughout the run of the program, not just when you're actually playing the game.

0

Share this post


Link to post
Share on other sites
There's no reason not to think of game state classes as very different from any other class. Like any other class, if there's information you want to pass to an object as you create it, then you can make it a parameter of the constructor.
0

Share this post


Link to post
Share on other sites

I don't see why you have to pass character data from one state to the next (in this case), because "logging in" and "getting character data" are two distinct activities, which can be executed in two distinct states: In your log-in state, you're trying to authenticate, and if you do, you transition into the "load" state, where you can get the relevant data from the network.

 

Some general comments relating to state machines: There are many cases where you don't really need to have a convoluted class hierarchy, and where setting a function pointer will work just fine.

 

I actually wrote a small Tetris game in C, where states, and state transitions, are just as simple as that.

 

You can see the code on my github, specifically in this file: states.c.

0

Share this post


Link to post
Share on other sites

I don't see why you have to pass character data from one state to the next (in this case), because "logging in" and "getting character data" are two distinct activities, which can be executed in two distinct states: In your log-in state, you're trying to authenticate, and if you do, you transition into the "load" state, where you can get the relevant data from the network.

 

Even if I do it that way, wouldn't I only be pushing the transfer of data between states to the load state?  

0

Share this post


Link to post
Share on other sites

As a side not on the original state system I would ditch the singleton behaviour from all the states, you can have different instances of the same state in a game. Some information shouldn't be stored in the states itself they only indicate in which state the game is. We stored player information for example in a player profile which was globally accesseable through a resource class that was passed in the constructor of a state. You then had multiple states to check whether the player had signed into a profile on the console, and then other states to check other things in the profile when needed.

0

Share this post


Link to post
Share on other sites

Even if I do it that way, wouldn't I only be pushing the transfer of data between states to the load state?  

 

You would no longer need to have a system for transferring data between states, because each state would be responsible for getting the data it actually requires.

 

If other states need to access this data somewhere along the line, they should be able to get it from some globally visible data structure.

0

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0