Hi! I was wondering if there is any undocumented script control or method that I could use to implement a beatjumping functionality to jump the playhead by one beat forward or backwards in a way similar to how Torq does it. I have not found a control to do this, so I have tried to do this on the script by computing:
rate' = 1 + rate * rateRange playposition' = playposition + 60 * rate' / delta / bpm / duration Where "delta" is the number of beats we want to jump and the rest are the standard Mixxx controls. First thing that I have noticed is that there seems to be a rounding error that make the play position disalign forward from the beatgrid when pressing the button several times. I have fixed this problem by replacing the 60 by 59.9, but, depending on the file, it still gets a bit forward or backwards when pressed several times. The second problem with this aproach is that properly synced tracks get quickly off when applying this operation while they play. This seems to be so because the play position is not compensated when setted taking into account the time spent during the computation of the script. This have got a bit better, yet way from perfect, by adding the following correction: if play playposition'' = playposition + latency / 1000.0 / duration Because of all these problems, I would like to know: 1. Is there any undocumented control or engine function that would let me better implement this function? 2. Does anybody know why I get this rounding errors in the non-playing case? A error that size seems to me that it is clearly not a problem of this floating point computation, but some offsetting that is applied to the playing position in the engine when set. 3. Should we modify the playposition control such that it compensates the elapsed time when set, or add a delta_playposition control instead for these purposes? Thanks! JP ------------------------------------------------------------------------------ Introducing Performance Central, a new site from SourceForge and AppDynamics. Performance Central is your source for news, insights, analysis and resources for efficient Application Performance Management. Visit us today! http://pubads.g.doubleclick.net/gampad/clk?id=48897511&iu=/4140/ostg.clktrk _______________________________________________ Get Mixxx, the #1 Free MP3 DJ Mixing software Today http://mixxx.org Mixxx-devel mailing list Mixxx-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/mixxx-devel