Using curses

TheDenominater · 12-01-2009, 06:30 PM

Hey,
I've built a very simple and small 'Lunar Lander' game using a combination of timers and curses. I've come to a point thought where I'd like to improve it and I'm stumped at what to do about a particular issue.

From how I've organized me curses, I can only detect on key press at a time. My basic loop structure is this:

Code:

while(1)
{
	c = getch();
	if (c != ERR)
	{
		if (c == ' ')
		{
		........
		}
		else if (c == 't')
		{
		.....
		}
	}
}

What happens because of this is that actions will be interrupted because of other key presses. Can I get past this limitation while still using curses? If there's a better way without curses I'd also like to know.

Thanks.

quzah · 12-01-2009, 06:42 PM

Push them all onto a queue, stack, whatever, as you press them, and pull them off as you run through your game loop.

Quzah.

MK27 · 12-01-2009, 06:45 PM

Make the condition:

Code:

while (ch=getch()) {

And then do EVERYTHING inside that loop. This guarantees ch can only have one value per iteration, so nothing has to be interrupted to check the keyboard.

You could use quzah's suggestion, but 1) I don't think it will be so simple unless you are threading this; 2) the loop should execute rapidly enough that this is not a real issue; 3) users hitting several key simultaneously need to learn to use the interface properly

TheDenominater · 12-01-2009, 06:59 PM

Hey,
Thanks for the replies. I'm not quite sure either of those will work if I understand them correctly. I should explain myself more.

My code consists mainly of two part: that continuous while loop for input and a timer function that gets called every 0.05 seconds. The way it's set up now pressing a key will set a variable that affects the outcome of the timer function. If you release that key the variable will return to it's 'un-pressed' state.

The problem I am facing now is that I want simultaneous key presses but I don't have them. Say the user is holding down the space-bar, but wants to press an arrow key. Pressing the arrow key will stop the loop from setting the 'space-bar' variable, but that's not what should happen, the space-bar should not be interrupted and continue after the user releases the arrow key.

I have a feeling I might have to fundamentally change how it works so that I can do that.

P.S. A related problem I have is that when you press a key it sets the value, pauses for a second, then start setting the value continuously. The same thing that happens as when you're typing and you hold down a key. I also want to change that.

12-01-2009, 06:30 PM	#1
TheDenominater Registered User Join Date: Nov 2009 Posts: 11	Using curses Hey, I've built a very simple and small 'Lunar Lander' game using a combination of timers and curses. I've come to a point thought where I'd like to improve it and I'm stumped at what to do about a particular issue. From how I've organized me curses, I can only detect on key press at a time. My basic loop structure is this: Code: while(1) { c = getch(); if (c != ERR) { if (c == ' ') { ........ } else if (c == 't') { ..... } } } What happens because of this is that actions will be interrupted because of other key presses. Can I get past this limitation while still using curses? If there's a better way without curses I'd also like to know. Thanks.
TheDenominater is offline

12-01-2009, 06:42 PM	#2
quzah +++ OK NO CARRIER Join Date: Oct 2001 Posts: 11,317	Push them all onto a queue, stack, whatever, as you press them, and pull them off as you run through your game loop. Quzah. __________________ Hundreds of thousands of dipshits can't be wrong. Are you up for the suck?
quzah is offline

12-01-2009, 06:45 PM	#3
MK27 dat is, vast staat Join Date: Jul 2008 Location: SE Queens Posts: 6,612	Make the condition: Code: while (ch=getch()) { And then do EVERYTHING inside that loop. This guarantees ch can only have one value per iteration, so nothing has to be interrupted to check the keyboard. You could use quzah's suggestion, but 1) I don't think it will be so simple unless you are threading this; 2) the loop should execute rapidly enough that this is not a real issue; 3) users hitting several key simultaneously need to learn to use the interface properly __________________ C programming resources: GNU C Function and Macro Index -- glibc reference manual The C Book -- nice online learner guide Current ISO draft standard CCAN -- new CPAN like open source library repository GDB tutorial #1 -- gnu debugger tutorials -- GDB tutorial #2 cpwiki -- our wiki on sourceforge Last edited by MK27; 12-01-2009 at 06:48 PM.
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12-01-2009, 06:59 PM	#4
TheDenominater Registered User Join Date: Nov 2009 Posts: 11	Hey, Thanks for the replies. I'm not quite sure either of those will work if I understand them correctly. I should explain myself more. My code consists mainly of two part: that continuous while loop for input and a timer function that gets called every 0.05 seconds. The way it's set up now pressing a key will set a variable that affects the outcome of the timer function. If you release that key the variable will return to it's 'un-pressed' state. The problem I am facing now is that I want simultaneous key presses but I don't have them. Say the user is holding down the space-bar, but wants to press an arrow key. Pressing the arrow key will stop the loop from setting the 'space-bar' variable, but that's not what should happen, the space-bar should not be interrupted and continue after the user releases the arrow key. I have a feeling I might have to fundamentally change how it works so that I can do that. P.S. A related problem I have is that when you press a key it sets the value, pauses for a second, then start setting the value continuously. The same thing that happens as when you're typing and you hold down a key. I also want to change that.
TheDenominater is offline

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