Batuhan Bozkurt wrote: > > So the required stimuli are a "beep" sound (which is a 3.5khz sine with > 7 ms duration) and a "flash" (which is basically a white circle visible > only for 20ms). > > The problem is, it is very hard for an object to "flash" with this short > duration. If you look at the patch you'll see that less than 50% of the > trials do not produce anything.
hmm, > > I have to come up with a workaround to this and I thought maybe if I can > syncronize the onset of the flash with the refreshing rate, I can at > least make the disk visible for all of the trials. I can sacrifice the > precision in terms of duration but that is bound to happen I guess. the first thing i noticed is that you are running Gem with the default framerate, which is 20 fps (50ms!) there is plenty of time where you can trigger the flash right after a render-cycle and the flash will disappear before the next one. so the first thing you ought to do is use a higher framerate, best choice will be the same rate as your monitor (60Hz): [gemwin 60] it's hard to display a flash for 10ms if every frame stays there for 50ms... :-) the next thing is to synchronize your trigger events with the gem-rendering. just insert a [t a b] object to the gemchain (e.g. [gemhead]), the 2nd outlet will band everytime the gemchain is executed (the actual rendering (buffer swapping) is done immediately after all gemheads have returned, which is 0 logical time after the bang (but some microsecs real time) fmadsr. IOhannes _______________________________________________ [email protected] mailing list UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list
