Roman Haefeli a écrit : > On Fri, 2007-10-12 at 00:48 +0200, cyrille henry wrote: >> Thomas O Fredericks a écrit : >>> "sync to vblank will sync swapping buffer with the screen frame rate, but >>> that's not the original question. >>> to my knowledge, there is no possibility to sync gem rendering with the >>> screen frame rate. >>> if you fix both at 60Hz, you can have jitter (not a lot, but some)." >>> >>> You are not technically syncing gem to the screen frame rate. >> yes >>> You are >>> syncing the open gl redraw to the framerate. >> yes >>> The GPU takes care of that. >>> >> i don't understand this. >> >> if you get gem to render a 60FPS, you will have 60fps based on the pd (cpu) >> clock. > > i don't know this by reading the code, but for me it would only make > sense to get the clock from the audio-card, nothing else. this is also > what i experienced, when pd was running on jackd, while jackd was > believing to be running at 44100Hz, while it was actually at 48000Hz. > all [metro]s were too fast and all pitches too high. the only objects, > that seems to work not with the audio-clock, that come to my mind, are > [cputime] and [realtime] (is that true?) > >> if you set your screen at 60fps, you will have 60fps based on the gpu. >> there is no way to make the cpu clock to be exactely the same speed as the >> gpu clock. >> so, sometime (specially with big patch), you can have desincronisation >> between this 2 clocks, even if they should be at the same speed. >> (there is a also a lot's of jitter in pd clock) > > what makes you think that? i 'd claim, that pd's clock is stable, unless > you get audio drop-outs.
gemhead 50 | t b b | | realtime | print you should have only 50. what i've got is : print: 46.48 print: 52.183 print: 52.213 print: 46.474 print: 52.186 print: 46.505 print: 52.192 print: 52.179 print: 46.512 print: 52.174 print: 52.209 print: 46.484 print: 52.179 print: 46.512 print: 52.159 (with audio off, nothing else than the gemwin and this 4 object in the patch) this jitter make it impossible to compute 1 and only 1 frame for each frame on the screen, even with sync on vblank. cyrille > > roman > > > > > ___________________________________________________________ > Der fr�he Vogel f�ngt den Wurm. Hier gelangen Sie zum neuen Yahoo! Mail: > http://mail.yahoo.de > > _______________________________________________ PD-list@iem.at mailing list UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list