Feedback CHOP


The Feedback CHOP stores channels from the current frame to be used in a later frame, without forcing recooking back one frame. It allows you to get the state of a CHOP as it was one frame or time slice ago.

For example, if you need the position or speed of an object from a frame ago in order to compute its position, displacement or speed at the current frame, you would select a CHOP containing those values, and it will output it a frame or time slice later.

CHOPs like the Lag CHOP and Filter CHOP look back in time (iterate) internal to the CHOP, but sometimes the output of a chain of CHOPs is needed as the input of the same chain one frame later.

It allows connecting CHOPs in circular loops without Infinite Recursion errors. It simply copies its input without cooking it first.


Parameters - Feedback Page

Output output - -

  • Previous Channels at Previous Time previous - Grabs the channels at prior time.
  • Previous Channels at Current Time shift - Grabs channels at current time.
  • Last Sample at Current Time sample - Uses the last sample received.

Delta Time delta - Time differential during feedback. If on, it adds a 'dt' channel whose value is the elapsed time since the last cook.

Reset reset -

Reset Pulse resetpulse -

Parameters - Common Page

Time Slice timeslice - Turning this on forces the channels to be "Time Sliced". A Time Slice is the time between the last cook frame and the current cook frame.

Scope scope - To determine which channels get affected, some CHOPs use a Scope string on the Common page.

Sample Rate Match srselect - - Handle cases where multiple input CHOPs' sample rates are different. When Resampling occurs, the curves are interpolated according to the Interpolation Method Option, or "Linear" if the Interpolate Options are not available.

  • Resample At First Input's Rate first - Use rate of first input to resample others.
  • Resample At Maximum Rate max - Resample to the highest sample rate.
  • Resample At Minimum Rate min - Resample to the lowest sample rate.
  • Error If Rates Differ err - Doesn't accept conflicting sample rates.

Export Method exportmethod - - This will determine how to connect the CHOP channel to the parameter. Refer to the Export article for more information.

  • DAT Table by Index datindex - Uses the docked DAT table and references the channel via the index of the channel in the CHOP.
  • DAT Table by Name datname - Uses the docked DAT table and references the channel via the name of the channel in the CHOP.
  • Channel Name is Path:Parameter autoname - The channel is the full destination of where to export to, such has geo1/transform1:tx.

Export Root autoexportroot - This path points to the root node where all of the paths that exporting by Channel Name is Path:Parameter are relative to.

Export Table exporttable - The DAT used to hold the export information when using the DAT Table Export Methods (See above).

Operator Inputs

  • Input 0 -
  • Input 1 -

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