forums.ps2dev.org

[redflyingpig]

Hi, I've written an initial testing program on PSP. I use the UP and DOWN buttons as input buttons, when hit, the character displayed changes. It works, only that the inputs are too sensitive. The character changes many times on one hit. Has anybody got the idea to improve this? What is the 'classic' or 'right' way to control input sensitivities? Here is part of my code:

[weltall]

try putting the result from keys also in a second variable and check if it's equal to the current, so the selected button wont do it's action every time the content of the while is executed like this:

[redflyingpig]

Thanks, weltall, but that does not give me the intended result. The character will not change any more when the same button is pressed repeatedly, if the code is modified like this, which is not what I intended to do.

I'm currenly thinking of using timestamps to make the input more 'stable'.

[weltall]

you need to wait a cicle before pressing the button again or it wont work, else you need to check that the button was pressed before and if so check how much time it was pressed, if so trigger a faster scrolling.
you could use cputicks you can find the function to get it from psppower if i remember correctly

[CyberBill]

One cycle isnt enough.

The typical way to do key holding is to set a timer when you press the key down, and once that timer reaches some value (400ms or so) you signal the output again, and then set the timer back to something like 300ms, so that the next signal only takes 100ms... This is how you get the effect of holding a keyboard key down.

Try it out..

OOOOOOOOOOOOOOOOOOOOOOOOOOOO :D

(This means you'll have to implement a timer system, as a counter is totally inaccurate)

[redflyingpig]

Could you give me more information about setting up a timer, like, which functions can be utilized to implement it?

[Arwin]

[CyberBill]

Dont use a counter.

[redflyingpig]

Thanks a lot, CyberBill. I know what you mean, it's a rather accurate solution, however, I've found another way, by simply adding a loop:

[CyberBill]

sceDisplayWaitVBlankStart() waits until the VSynch gets called to the OS. Its tied into the screen refresh rate, the PSP refreshes 60 times a second. So calling it 6 times in a tight loop essentially is the same thing as doing a sceKernelDelayThread( 6 * (1000000/60) ); which should be 100 milliseconds or 100,000 microseconds..

The upside to this solution is that its easy and gets the job done. The bad side is that the code isnt going to port well if you plan on doing a game because some code needs to have full control of the graphics system and game loop, and this throws it out of whack. And dont even think about trying to do that in a multithreaded situation where you have some other system drawing, very strange results I'm sure!!

[redflyingpig]

Thanks a lot for help!

[JustChris]

I decided to ask the following here because it's related to the topic, instead of making another topic:

How do I detect when a button is released?

For example, I need to make an event happen only once when the button is pressed/held down. And maybe, I want something else to happen after the button is released.[/code]

[weltall]

you could do something like that if it's only one button
sceCtrlReadBufferPositive(&pad,1);
if(pad.Buttons & PSP_CTRL_BUTTON)
{
//do action
}
else
{
//stop action
}

[CyberBill]

sceCtrlReadBufferPositive() will set the "buttons" flags with the current state of the buttons (if the flag is present then that means the button is pressed down, if its not present then the button is not pressed).

The code from weltall only handles half of this. What you really want to do is detect not when the button is not pressed, but when the button's state changes from not pressed to pressed and back.

So:

[nerdcore]

One easy solution for slowing input would be to sleep the input thread using sceKernelDelayThread(int microsecs).