Re^2: SDLx::App event loop

The example provided follows the SDL_key_repeat solution I explained below. It is implicit when creating the app. As an aside, my exaple is essentially exactly like theirs except I've got things split up into Moose classes and it's a bit more messy. It is hard to post code of that nature in any sort of intelligible way. It is entirely safe to assume my example is the same as the two squares example.

Following what their example is doing, the longer I hold an arrow key, the more events get pumped, the more the square moves. It is essentially a timed release of an event, by limiting how many key_repeat signals get translated into events.

This satisfies my need for some things. Maybe my question is more a timer question then, since I would like to have a certain event only happen at specific intervals. With the above example and solution, I could only have one specific delay for many events. Imagine I wanted to shoot bullets frontwards at my key_repeat speed, but then fire one backwards every 2*key_repeat. I don't have a way to do that with the built in key_repeat functions, and am also just as clueless about how to use a timer without blocking.

With these things being called "callbacks" is this non-blicking by default? I've only used callbacks in a Net::SNMP non-blocking context. Are these essentially the same types of things? Is SDLx already trying to make things this easy for me?

Thanks for your quick reply

Ransom

Comment on Re^2: SDLx::App event loop

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Re^3: SDLx::App event loop by zentara (Cardinal) on Jun 11, 2012 at 19:43 UTC
With these things being called "callbacks" is this non-blicking by default? Well `my $app = SDLx::App->new(); .... $app->run;` [download] is an eventloop system. It schedules events as you request them. You can use SDLx without the eventloop, or make your own. See Re: Tk Game Sound demo-with SDL where I use the Tk eventloop with SDL. Generally in eventloop systems, timers and IO watchers can run simultaneously in a non-blocking manner, but keyboard input may need to be in a separate thread. If you are using Moose, that may be having an unexpected effect. It's all hard to say, when we are just speculating on unseen code, but timers can run non-blocking, it depends on what the timer is doing. Possibly you could use a key_press_down to start a timer, which every 20 forward-fire cycles, will do one backward fire. Then on the keypress_up, you cancel the timer. I probably could do it in Tk or Gtk2, but I am unfamiliar with all the SDL code. SDL timers seem to address your blocking ( timeslice ) problems. Generally timers can be used 2 ways, one is a one-shot timer, the other will repeat itself until you tell it to stop. This is where the returning a 1 or 0 , TRUE or FALSE, comes into play. I'm not really a human, but I play one on earth. Old Perl Programmer Haiku ................... flash japh	[reply] [d/l]
Re^4: SDLx::App event loop by Ransom (Beadle) on Jun 11, 2012 at 19:57 UTC
Updated OP with code. I'm starting to think this is a timer issue coupled with my lack of understanding of event loops. Thanks you for all your help so far.	[reply]
Re^5: SDLx::App event loop by zentara (Cardinal) on Jun 12, 2012 at 08:23 UTC
my ... understanding of event loops It isn't SDL, it's Tk; but see Anatomy of an Eventloop. It may give you an idea of what is going on in SDL. P.S. I tried to run your code, but couldn't find what "use btype" is, or "ship.pm". Your code is indeed a batch of spaghetti. :-) I'm not really a human, but I play one on earth. Old Perl Programmer Haiku ................... flash japh	[reply]
Re^6: SDLx::App event loop by Ransom (Beadle) on Jun 12, 2012 at 12:04 UTC