I want to thank all of you for the suggestions you provided me: now the program is working really better. After some tests, I noticed that If I load images before the time I need timing accuracy results are indeed good: sometimes I lose 1 msec, but it is not so dramatic for my purposes. The class provided by Brian Fisher provides also really accurate results, the problem is that, if I am not wrong, any signal could terminate the sleep (since users should interact with the keyboard after images are displayed, I fear that they could accidentally hit one key before the right time, namely after image disappear): is pygame.time.wait more accurate than time.sleep?
Francesco On Sat, May 24, 2008 at 9:19 AM, Noah Kantrowitz <[EMAIL PROTECTED]> wrote: > > On May 24, 2008, at 12:08 AM, Brian Fisher wrote: >> >> On Fri, May 23, 2008 at 9:15 PM, Noah Kantrowitz <[EMAIL PROTECTED]> wrote: >> >> Anywhere you need that kind of timing accuracy, python is probably not the >> right tool for the job. I would recommend using plain SDL in C, you will >> likely find it much more stable timing-wise. >> >> You may be right that python is a poor tool in cases where you need timing >> accuracy for stuff where you execute a lot of python code, but I really >> doubt python would pose any limitation for just showing an image for a >> specific amount of time. Task switching, timer resolution and video refresh >> all represent larger chunks of time than python code execution, and also the >> approach to doing the timing matters a lot more than whether python is >> executing it or c is for most tasks. > > Beware the cycle detector. It introduceth non-deterministic execution > profiles. > > With that disabled, and care taken to make sure nothing will be loaded off > disk when you don't expect it (lazy module loading or activation for > example), it should be okay, but with C you know exactly what code is > running and when. > > A note on the original code, you probably want to use > pygame.time.get_ticks(), not time.time(). > > --Noah >
