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Expression CHOP

Summary

The Expression CHOP allows you to modify input channels by using math expressions. Up to six expressions are available. Each input channel is modified by exactly one expression, and the expressions are looped for multiple channels.

The output is the same length and set of channels as the first input, but its sample values are changed according to the expressions.

An expression is applied to each keyframe value or raw sample. There are up to six expressions. If there are more channels coming from input 0, the expressions are recycled. A repeat parameter controls how many channels to apply the first expression to before going on to the second expression.

The corresponding input values are me.inputVal in the expressions. me.inputs[1][0] gets from the first channel of the second input.

See also Evaluate DAT for easy evaluation of any expression.

PythonIcon.pngexpressionCHOP_Class


Parameters - Expression Page

Channels per Expr chanperexpr - The number of channels that use the current expression before the next expression is selected.  

Limit Output Channels limitexpr -  

Number of Channels limitnum -  

Expression 0 expr0 - Enter your expressions here. The input values are me.inputVal in the expressions. me.inputs[1]['chan1'] gets from the channel chan1 of the second input.  


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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