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Started by TRYCORP May 01, 2006 06:58 PM

6 comments, last by Lazy Foo 17 years, 11 months ago

TRYCORP

122

Author

May 01, 2006 06:58 PM

I'm not new to programming, but I am new to game programming. I know Java, C, and C++. I've done simulation and analysis, application, and some other various random items, (ex: Web Crawler), but I have never had to deal with a user inputing commands while something is running save one instance and I used threads. So, onto my question. Exactely how does one interupt all the updating and rendering etc that goes on in a main game loop with user commands. For example in tetris, with blocks moving down, and frames redrawing, etc. How do you take in the user's input without stopping the process? Do you have to use multiple threads or is there a simpler way I am unaware of?

Lesson Number 4:"Blades don't need reloading."-- The Zombie Survival Guide

dave

2,188

May 01, 2006 07:00 PM

Its just a case of doing it all at once, in my experience.

User Input
Phyics
AI
Render

Dave

Lazy Foo

1,113

May 01, 2006 07:07 PM

Quote:Original post by TRYCORP
So, onto my question. Exactely how does one interupt all the updating and rendering etc that goes on in a main game loop with user commands. For example in tetris, with blocks moving down, and frames redrawing, etc. How do you take in the user's input without stopping the process? Do you have to use multiple threads or is there a simpler way I am unaware of?

It's called event driven programming.

basically loop like this
while(true)
{
handle events
do calculations
render
}

in the case of tetris
while(true)
{
check for button presses and deal with them accordingly
move pieces/check for rows/etc
show blocks
}

I have plenty of small examples on my site</incredibly shameless plug>

Learn to make games with my SDL 2 Tutorials

Iftah

413

May 01, 2006 07:10 PM

usualy you have some event driven framework (such as win32, or SDL) and your game loop "peeks" for messages. If no messages are available it loops "update" and "render".
If input message is there it handles input (either update then or flags some booleans for next loop "update"

note: both "update" and "render" use a timer (clock) to know how much time passed from previous loop to move things smoothly.

Iftah.

TRYCORP

122

Author

May 01, 2006 07:15 PM

Ah, ok, are thier any non-platform dependent event driven frameworks out thier? Something built in ANSI standard?

Lesson Number 4:"Blades don't need reloading."-- The Zombie Survival Guide

TRYCORP

122

Author

May 01, 2006 07:17 PM

I should have visited your website before asking that question Lazy. Right there on the main page...

"SDL is used as the API because it is cross platform, and relatively easy to use."

Thanks guys.

Lesson Number 4:"Blades don't need reloading."-- The Zombie Survival Guide

Fluffy-Bunny

120

May 01, 2006 07:18 PM

Yes, there is. Try GLUT.