Logic CHOP


The Logic CHOP first converts channels of all its input CHOPs into binary (0 = off, 1 = on) channels and then combines the channels using a variety of logic operations.

NOTE: The Logic CHOP is superceded by more convenient operators like the CHOP Execute DAT or the Text DAT which will run their scripts when CHOP channels change.

The Logic CHOP performs logic operations on the samples in CHOP channels. The channels of a CHOP can be combined into one channel, and several CHOPs can be combined into one CHOP.

With one input CHOP, you can invert the values of each sample. You can also do logic operations on the samples of one channel by the samples in the other channels, reducing N channels down to one. You can combine by applying an "or", "and", etc..

With two or more CHOP inputs, you can combine the channels in one CHOP with the channels in all the other CHOPs, reducing N CHOPs to 1.

To do math operations (add, multiply, ...) between channels or CHOPs, use the Math CHOP.


Parameters - Logic Page

Convert Input convert - - This menu determines the method to convert inputs to binary:

  • Off When Zero nonzero - Returns a logical 0 when channel value is zero;
    Non zero values return 1.
  • Off When Zero Or Less pos - Returns a logical 0 when a channel value is zero or less; and 1 when values are positive.
  • Off When Outside Bounds bound - Returns 0 when channel value is outside the bounds set by the Bounds parameter below.
  • On When Value Changed valchange - Returns 1 when the channel value changes.
  • On When Channel Name Changed namechange - Returns 1 when the channel name changes.


Channel Pre OP preop - - Once converted by the Convert Input stage, Channel Pre OP defines a unary operation on each input sample:

  • Off off -
  • Invert invert - Changes 0 to 1; and 1 to 0.
  • Toggle toggle - Causes each 0 to 1 transition of the input channel to switch the current state between 0 and 1.
  • Radio Button radio - Only one channel per input can be on at once. If another channel turns on, the previously "on" channel is turned off.
  • Last Two On radio2 - This is like Radio Button, but it keeps up to two channels on. If followed by a Lag CHOP, it is useful for blending between pairs of poses.
  • Rising Edge rise - On for one sample only, at each place where a channel goes from off to on.
  • Falling Edge fall - On for one sample only, at each place where a a channel goes from on to off.

Combine Channels chanop - - Takes the first input and combines its channels, then the second input and combines its channels, and so on.

  • Off off -
  • And and -
  • Or or -
  • Exclusive Or xor -
  • Not And nand -
  • Not Or nor -
  • Equivalence eqv -
  • Lowest Index On lowest -
  • Highest Index On highest -

Combine CHOPs chopop - - Combine CHOPs combines the first channels of each CHOP, the second channels of each CHOP, etc.. Channels between inputs can be combined by number or name. Combining (Logic) Operations are:

  • Off off -
  • And and - On if all inputs are on, otherwise off.
  • Or or - On if at least one input is on, otherwise off.
  • Exclusive Or xor - On if one input on, but not more than one.
  • Not And nand - Off if all inputs are on, otherwise on.
  • Not Or nor - Off if at least one input is on, otherwise on.
  • Equivalence eqv - On if inputs are equal (all on or off), otherwise off.
  • Lowest Index On lowest - Gives the lowest index of the channel that is currently on,
    or -1 if no channels are on.
  • Highest Index On highest - Gives the highest index of the channel that is currently on on,
    or -1 if no channels are on.


Match by match - - Channels are matched between inputs by Channel Name or Channel Number.

  • Channel Number index -
  • Channel Name name -

Align align - - Inputs that don't start at the same frame can be aligned. Se the section, Align Options.

  • Automatic auto -
  • Extend to Min/Max none -
  • Stretch to Min/Max stretch -
  • Shift to Minimum start -
  • Shift to Maximum end -
  • Shift to First Interval shift1 -
  • Trim to First Interval trim1 -
  • Stretch to First Interval stretch1 -
  • Trim to Smallest Interval trim -
  • Stretch to Smallest Interval squash -

Bounds bound - - Set lower and upper bounds for when Convert Input is set to Off When Outside Bounds.

  • boundmin -
  • boundmax -

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 -

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