Logic CHOP

Summary

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NOTE: The Logic CHOP is superceded by more convenient operators like the CHOP Execute DAT or the Text DAT which will run their scripts when CHOP channels change.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

logicCHOP_Class

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. 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: -

Info CHOP Channels

Extra Information for the Logic 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: Latest\n2021.100002018.28070before 2018.28070

An Operator Family which operate on Channels (a sequence of numbers (Samples)) which are used for animation, audio, mathematics, simulation, logic, UI construction, and data streamed from/to devices and protocols.

Any of the procedural data operators. OPs do all the work in TouchDesigner. They "cook" and output data to other OPs, which ultimately result in new images, data and audio being generated. See Node.

A Time Slice is the time from the last cook frame to the current cook frame. In CHOPs it is the set of short channels that contain the CHOP channels' samples between the last and the current cook frame.

A parameter in most CHOPs that restricts which channels of that CHOP will be affected. Normally all channels of a CHOP are affected by the operator. TOPs have Channel Mask, a similar feature.

samples-per-second of a CHOP. Each CHOP in your network has a sample rate. In contrast, the overall timeline has a Frame Rate, which is the number of frames to cook and display per second, generally your monitor display frequency, default 60.

Exporting is the connection of CHOP channels to parameters of operators. The output of each exporting CHOP is one or more channels, active only while the CHOP Viewer is on. The current value of a channel can be exported to a parameter of any operator, overriding that parameter's value. See Parameter.

An Operator Family that manipulates text strings: multi-line text or tables. Multi-line text is often a python Script or GLSL Shader, but can be any multi-line text. Tables are rows and columns of cells, each containing a text string.

The location of an operator within the TouchDesigner environment, for example, /geo1/circle1, a node called circle1 in a component called geo1. The path / is called Root. This path is displayed at the top of every Pane, showing which Component's network you are currently in. To refer instead to a filesystem folder, directory, disk file or http: address, see Folder.

Every operator in TouchDesigner has a set of control Parameters that can be integer or floating point numbers, menus, binary toggles, text strings or operator paths, which determine the output of the operator.

TouchDesigner is a hierarchy of components. "root" is the top-most network in the hierarchy. The Network Path or Path for root is simply /. A typical path is /project1/moviein1.