Close

Privacy policy

Follow us

https://www.instagram.com/touchdesigner/
https://www.facebook.com/TouchDesigner
https://twitter.com/1null1
https://www.youtube.com/TouchDesignerOfficial
All
User Guide
Forum
Tutorials
Events & Workshops
Features
Community
Showcase
Resources
  1. Home
  2. Feedback CHOP

    Feedback CHOP

    Summary

    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.

    PythonIcon.pngfeedbackCHOP_Class


    Parameters - Feedback Page

    Output output - ⊞ - Choose what to output from this menu.
    • 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 - Activates feedback when set to 0. Disables feedback when set to 1. When disabled, the Feedback CHOP passes thru the data connected to its input.

    Reset Pulse resetpulse - Resets the feedback in a single frame when clicked.


    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. See Pattern Matching.

    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: -


    Info CHOP Channels

    Extra Information for the Feedback CHOP can be accessed via an Info CHOP.

    Common CHOP Info Channels

    • start - Start of the CHOP interval in samples.
    • length - Number of samples in the CHOP.
    • sample_rate - The samplerate of the channels in frames per second.
    • num_channels - Number of channels in the CHOP.
    • time_slice - 1 if CHOP is Time Slice enabled, 0 otherwise.
    • export_sernum - A count of how often the export connections have been updated.

    Common Operator Info Channels

    • total_cooks - Number of times the operator has cooked since the process started.
    • cook_time - Duration of the last cook in milliseconds.
    • cook_frame - Frame number when this operator was last cooked relative to the component timeline.
    • cook_abs_frame - Frame number when this operator was last cooked relative to the absolute time.
    • cook_start_time - Time in milliseconds at which the operator started cooking in the frame it was cooked.
    • cook_end_time - Time in milliseconds at which the operator finished cooking in the frame it was cooked.
    • cooked_this_frame - 1 if operator was cooked this frame.
    • warnings - Number of warnings in this operator if any.
    • errors - Number of errors in this operator if any.


    TouchDesigner Build: