Scan CHOP

Summary

The Scan CHOP converts a SOP or TOP to oscilloscope or laser friendly control waves. The output is usually in the audible range and can be heard directly via an Audio Device Out CHOP, or used to drive the X and Y deflector inputs of an oscilloscope, or a laser projector recreating the imagery. The output can also be visualized through use of a Limit SOP.

A sample component found at: Op to Audio CHOP example

A sample video can be found at: Total Internal Reflection

See also: EtherDream CHOP, EtherDream DAT

scanCHOP_Class

Parameters - Scan Page

Source OP source - ⊞ - Choose the source node family.

• TOP top - A raster image is converted to control signals by converting each pixel's location to X and Y amplitude values.

• SOP sop - A geometry is converted to control signals by converting each point's position to X and Y amplitude values.

• CHOP chop - A waveform is converted to control signals by converting each graph into corresponding horizontal and vertical offsets.

Sample Rate rate - Samples per second, the output sample rate.

Swap Output swap - Reverse the X and Y channel outputs.

X Scale xscale - Scale the x amplitude.

Y Scale yscale - Scale the y amplitude.

Rotate rotate - Specified in degrees, rotates the output x,y values.

Randomize Samples randomize - Output all samples in a random order. Creates a fuzzy chaotic image on an oscilloscope.

Output Color color - If on, r,g,b channels are created.If on, r,g,b channels are created.

Red Scale redscale - Scale the output r channel.

Green Scale greenscale - Scale the output g channel.

Blue Scale bluescale - Scale the output b channel.

Blanking Count blankingcount - In the case of SOP input, the number of black/off positions to insert between geometry primitives. In the case of TOP input, the number of black/off positions to insert between full raster scans. Color output must be enabled.In the case of SOP input, the number of black/off positions to insert between geometry primitives. In the case of TOP input, the number of black/off positions to insert between full raster scans. Color output must be enabled.

Parameters - TOP Page

A raster image is converted to control signals by converting each pixel's location to X and Y amplitude values. The luminance is controlled by how long each sample is "drawn" on the scope. Since the output is low bandwidth, different resampling and ordering options are available for minimizing (or enhancing) flicker.

TOP top - Path to the TOP node.

Width width - The number of columns to resample the image at.

Height height - The number of rows to resample the image at.

Level level - The number of brightness levels each pixel can have.

Auto Reduce limit - Automatically reduce the number of rows and columns dynamically to keep the output frame rate

at a constant level.

Layered layered - Output the pixels in order of brightness, else they are output left to right for each row.

Interleave interleave - ⊞ - Controls the order in which rows are output to minimize flicker.

• Sweep sweep - The rows are output in order, from top to bottom.

• Even Odd evenodd - The rows are output in two passes, first even, then odd.

• Max max - The rows are output in fully interleaved fashion.

Parameters - SOP Page

Every point in a SOP creates a frame-buffered, stereo audio sample, where the SOP vertex X is placed on the X channel and Y is placed on the Y channel. The oscilloscope output thus contains no aliased lines, just razor-sharp vectors.

SOP sop - Path to the SOP node.

Vertex Order vertexorder - Output the points in the same order as the vertices of each polygon, instead of the order in which the points are defined in the geometry.

Limit Step Size limitstep - Breakup long x,y jumps into several smaller incremental jumps.

Step Size stepsize - The distance each x,y can change when above option enabled.

Vertex Repeat vertexrepeat - Repeat each vertex of the each primitive multiple times.

Camera camera - Project the geometry onto a 2D plane from this camera, otherwise, only the original x,y components of the geometry are used.

Parameters - CHOP Page

A waveform is converted to control signals by converting each graph into corresponding horizontal and vertical offsets, reproducing the original CHOP waveform. The CHOP should not be Time Sliced, but instead have some length (example a Trail CHOP or animated Wave CHOP).

CHOP chop - Path to the CHOP node.

Trigger trigger - The output graph will begin where its value exceeds this value. This allows for steady 'frozen' waveforms, analagous to an oscilloscope triggered sweep.

Trigger Value triggerval - The value to begin the trigger.

Trim trim - Limit the length of the CHOP to be scanned.

Trim Value trimval - The length of the CHOP to be scanned.

Trim Units trimunits - Select the units to use for this parameter, Samples, Frames, or Seconds.

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).

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.

An Operator Family that creates, composites and modifies images, and reads/writes images and movies to/from files and the network. TOPs run on the graphics card's GPU.

A Operator Family that reads, creates and modifies 3D points, polygons, lines, particles, surfaces, spheres and meatballs. Particles and point clouds are now done primarily on the GPU using TOPs.

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.

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.

A sequence of vertices form a Polygon in a SOP. Each vertex is an integer index into the Point List, and each Point holds an XYZ position and attributes like Normals and Texture Coordinates.

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.

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.

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.