I’m working on a project using osc to drive an index that looks up values from a chan file and the playback glitches on a regular interval. I hooked up a trail chop to a chan with the $F value in a blank project and I notice the same hiccup every second or so. Is this a common issue? Any advice on how to stream an index with as little noise as possible? I know filtering can resolve this but I’m trying to avoid delay as much as possible.
Thanks,
Tarik
Dell Precision T3500
Quadro FX 3800
Touch Designer Pro Build 16360
Hi Tarek.
The Filter CHOP has a Type option called ‘Ramp Preserve’.
It assumes a ramp starting at 0 and climbing linearly.
It was designed with incoming $F ramps in mind.
The periodic glitch you see sounds like the queue automatically adjusting itself once per second to try and reach a target length.
How are you receiving the $F values exactly? (What type of operator is receiving them).
As a test I created a blank touch project, made a constant chop with the value $F, and hooked it up to a trail. No OSC involved. Instead of seeing a linear stream, I would get bumps at a regular interval. What I found was that unplugging a second display caused the glitches to go away. So I’m wondering if its a hardware issue, perhaps with the nvidia card. I thought it could be the result of a bad cable because switching the cable helped at one point, but no, the problem persists.
Thanks for the “Ramp Preserve” suggestion. I will try that out. And I will look further into optimizing the OSC node.
What you are seeing is the results of timesliced data vs. non-timesliced data. The value coming $F takes on a single value on any given frame, so if your system drops a frame, then you’ll see a step on the data in the Trail CHOP.
This is different from timesliced data, such as something generated from the Count CHOP for example, which will ‘go back in time’ to calculate values on missed frames.
For OSC In CHOP, as long as your source is supplying exactly 60 frames/s worth of data and isn’t missing frames, then you will also benefit from this timeslicing, since the OSC In CHOP will have extra data to fill in missed frames.