Transform CHOP

From TouchDesigner Documentation
Jump to: navigation, search

Summary
[edit]

The Transform CHOP takes transformations in various formats, applied operations to them, and outputs them in various formats. It can be used to:

  • Change the position and orientation of an object.
  • Convertion transforms one format to another format.
  • Convert a set of transform channels with a certain transform order into an equivalent set of channels with a different transform order.
  • Change the direction, starting point and scale of motion capture data.

Three transform formats exists:

  • Transform with Euler angles for rotation. These are defined by channels with suffixes: tx ty tz, rx ry rz, sx sy sz and an optional transform and rotate order xord and rord.
  • Transform with Quaternion for rotation. These are defined by channels with suffixes: tx ty tz, qx qy qx qw, sx sy sz and an optional transform order xord.
  • A 4x4 or 3x3 matrix. These are defined by channels with suffixes: m00, m10, m20, m30, m01, m11... m33. Where the notation is m[row][col]. The matrix should be be in column-major order, that is to say, the translate portion should be in m03, m13, m23. The 4th row and column can be omitted to use a 3x3 matrix instead. Unlike the other formats, this format can not have arbitrary missing channels. Either 9 channels for 3x3 or 16 channels for 4x4 matrices must be provided.

The first two transform formats can be specified with missing channels, in which case default values will be used. 0s for translates and rotates, 1s for scale, and (0,0,0,1) for quaternion.

Frequently the input channels come from an Object CHOP or Parameter CHOP. Examples are:

  • geo1:tx geo1:ty geo1:tz geo1:rx ...
  • headtx headty headtz headrx
  • tx ty tz rx ... (what you would get from a Parameter CHOP)
  • cam1:m00 cam1:m10 cam1:m20 .... cam1:m33

Any of the above defines a transformation matrix. Multiple transform 'sets' can be specified by channels having different prefixes. Different sets using different formats can be all in the same CHOP. Formats can not be mixed within a set though. Each set will be combined with sets from the other input, and the transform on the 'Transform' page to create final transforms for each set.

If no inputs are connected to the CHOP, it will output the transform generated from the 'Transform' page.

If inputs are connected, the output will contain the same number of samples as the first input. Samples will be combined between the inputs 1:1, that is, the start/end range and the sample rate of the inputs are ignored. If the second input contains less samples than the first one, the extend conditions for that CHOP will be used to determine values for the samples coming from the 2nd CHOP that are out of range.

If multiple sets are provided, they will be matched 1st-to-1st set, 2nd-to-2nd set. If there are less sets in the second input than the first one, then it will loop over the sets. E.g if the first input as 5 sets and the second input as 2 sets, the matching will be 1st-to-1st, 2nd-to-2nd, 3rd-to-1st, 4th-to-2nd and 5th-to-1st.

The inputs will be combined together first, then the result from that will be combined with the transfrom defined on the 'Transform' page.

The channels of a Transform CHOP are frequently exported back to objects.

PythonIcon.pngtransformCHOP_Class


Parameters - Input Page

This page defines what the incoming channels' transform order is assumed to be. Using the incoming channels and the transform order here, a matrix for the incoming channels in built. It is then multiplied by the transformation matrix defined by the Transform page and output.

Any missing translation, rotation or scale channels will default to zero (or one in the case of scale).

Custom Input Orders custinputorders - This allows the input order, if provided, to be ignored and overridden by a custom order chosen by the following two parameters.  

Transform Order inxord - - Changing the Transform order will change where things go much the same way as going a block and turning east gets you to a different place than turning east and then going a block. In matrix math terms, if we use the 'multiply vector on the right' (column vector) convention, a transform order of Scale, Rotate, Translate would be written as T * R * S * Position

  • Scale Rotate Translate srt -
  • Scale Translate Rotate str -
  • Rotate Scale Translate rst -
  • Rotate Translate Scale rts -
  • Translate Scale Rotate tsr -
  • Translate Rotate Scale trs -

Rotate Order inrord - - As with transform order (above), changing the order in which the rotations take place will alter the final position and orientation. A Rotation order of Rx Ry Rz would create the final rotation matrix as follows R = Rz * Ry * Rx

  • Rx Ry Rz xyz -
  • Rx Rz Ry xzy -
  • Ry Rx Rz yxz -
  • Ry Rz Rx yzx -
  • Rz Rx Ry zxy -
  • Rz Ry Rx zyx -

Input 0 Pre Operation input0preop - - Operation(s) to apply on the transforms on Input 0, before they are combined with other transforms.

  • None none - No operation is applied.
  • Invert invert - Invert the transform.
  • Transpose transpose - Transpose the transform. This only has an effect for matrix format transforms.
  • Invert Transpose inverttranspose - Invert and Transpose the transform. The transpose will only be done if the input is a matrix format transform.

Input 1 Pre Operation input1preop - - Operation(s) to apply on the transforms on Input 1, before they are combined with other transforms.

  • None none - No operation is applied.
  • Invert invert - Invert the transform.
  • Transpose transpose - Transpose the transform. This only has an effect for matrix format transforms.
  • Invert Transpose inverttranspose - Invert and Transpose the transform. The transpose will only be done if the input is a matrix format transform.

Input Operation inputoperation - - The operation that should be applied between transforms coming from Input 0 and Input 1. Refer to the main description of this node for an explanation of how multiple samples and/or transform sets are combined between the two inputs.

  • Input 0, then Input 1 input0input1 - The operation will be input1 * input0. It it ordered this way since ultimately the transform is applied to a position/vector in the form input1 * input0 * Position, so the input0 operation is done first.
  • Input 1, then Input 0 input1input0 - The operation will be input1 * input0.


Parameters - Transform Page

This page defines an additional transform that can be combined with the transform created by combining the inputs, if any. If the node has no inputs connected then the transform generated from this page will be what is output from this node.

Transform Order xord - - See description from earlier Transform Order parameter.

  • Scale Rotate Translate srt -
  • Scale Translate Rotate str -
  • Rotate Scale Translate rst -
  • Rotate Translate Scale rts -
  • Translate Scale Rotate tsr -
  • Translate Rotate Scale trs -

Rotate Order rord - - See description from earlier Rotate Order parameter.

  • Rx Ry Rz xyz -
  • Rx Rz Ry xzy -
  • Ry Rx Rz yxz -
  • Ry Rz Rx yzx -
  • Rz Rx Ry zxy -
  • Rz Ry Rx zyx -

Translate t - - XYZ translation values.

  • X tx -
  • Y ty -
  • Z tz -

Rotate r - - XYZ rotation, in degrees.

  • X rx -
  • Y ry -
  • Z rz -

Scale s - - XYZ scale to shrink or enlarge the transform.

  • X sx -
  • Y sy -
  • Z sz -

Pivot p - - XYZ pivot to apply the above operations around.

  • X px -
  • Y py -
  • Z pz -

Pre Operation preop - - Operation(s) to apply on the transforms generated by the above parameters, before it is combined with other transforms.

  • None none - No operation.
  • Invert invert - Invert the transform.

Multiply Order multiplyorder - - Controls how the input transform(s) are combined with the transform specified on this page. The below two descriptions use a multiply "vector on the right" convention (column vectors).

  • Input, then Transform Page inputxformpage - The transforms will be combined as Transform Page * Input.
  • Transform Page, then Input xformpageinput - The transforms will be combined as Input * Transform Page.


Parameters - Output Page

This page controls what information is output from the node.

Post Operation postop - - Optionally applied one last operation to the final generated transform before it is output.

  • None none - No operation.
  • Invert invert - Invert the transform.
  • Transpose transpose - Transpose the transform. This only has an effect for matrix format transforms.
  • Invert Transpose inverttranspose - Invert and Transpose the transform. The transpose will only be done if the input is a matrix format transform.

Output output - - Specify the format the transform will be output in.

  • Transform (Euler) transform - The standard Translate, Rotate and Scale channels. t[xyz], r[xyz], s[xyz]. Will also include xord and rord channels for Transform and Rotate Order, unless 'Include Order Channels' is turned off.
  • Transform (Quaternion) transformquat - Translate, Quaternion (for rotation) and Scale channels. t[xyz], q[xyzw], s[xyz]. Will also include xord channel for Transform Order, unless 'Include Order Channels' is turned off.
  • 4x4 Matrix mat - 16 channels for a 4x4 matrix. The channels will be output in column-by-column order. That is, with the last 4 channels being the 'translate' portion of the matrix.
  • 3x3 Matrix mat3 - 9 channels for a 3x3 matrix. This includes the rotation and the scale, but not the translation.
  • Position position - The final position of the transform in space. This doesn't include any orientation information.

Determinant determ - When outputting a matrix, it's determinant can also be output by enabling this parameter.  

Un-matched Channels unmatchedchans - - Controls how channels that don't match the naming convention for the various transform format are treated.

  • Warn warn - Give a warning if transform channels that don't match any of the naming convenstions are found.
  • Ignore ignore - Ignore (give no warning) if channels that don't match the naming convention are found.
  • Delete delete - Delete all channels that don't match any of the naming conventions.

Custom Output Orders custoutputorders - By default the output transforms will use the orders given on teh Transform page. Enabling this allows for custom orders to be used for the transform that is output. This doesn't change the transform itself, but the values of the channels will likely change since they are combined in a different order to obtain the same overall transform.  

Transform Order outxord - - See description from earlier Transform Order parameter.

  • Scale Rotate Translate srt -
  • Scale Translate Rotate str -
  • Rotate Scale Translate rst -
  • Rotate Translate Scale rts -
  • Translate Scale Rotate tsr -
  • Translate Rotate Scale trs -

Rotate Order outrord - - See description from earlier Rotate Order parameter.

  • Rx Ry Rz xyz -
  • Rx Rz Ry xzy -
  • Ry Rx Rz yxz -
  • Ry Rz Rx yzx -
  • Rz Rx Ry zxy -
  • Rz Ry Rx zyx -

Include Order Channels includeorderchans - Specified if the 'xord' and 'rord' channels should be output from this node. 'xord' will be output for 'Transform (Euler)' and 'Transform (Quaternion)' modes. 'rord' will be output for the 'Transform (Euler)' mode. The matrix and position modes do not include orders.  

Continuous Rotations continuousrotations - In the case the input has multiple samples, this will attempt to keep rotations of neighbouring samples continuous. Basically, it tries to avoid 360 degree jumps. 360-> 361 instead of 360 -> 1 (which is the same two rotations.  

Use Rotation Hint usehint - An initial rotation hint given in r[xyz] degrees to try to stay continuous against. Turning this on and using the Hint parameter below allows you to specify approximate starting values for the rotation channels produced. This allows you to change the rotation channel solution to a specific starting point (e.g. for camera output control).  

Hint hint - - Specify approximate starting values for the rotation channels produced.

  • Hint hintx -
  • Hint hinty -
  • Hint hintz -


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 - One or more transform sets, as defined by the allowable formats described at the start of the article.
  • Input 1 - One or more transform sets, as defined by the allowable formats described at the start of the article.

TouchDesigner Build:

CHOPs
Ableton Link • Analyze • Angle • Attribute • Audio Band EQ • Audio Device In • Audio Device Out • Audio Dynamics • Audio File In • Audio File Out • Audio Filter • Audio Movie • Audio NDI • Audio Oscillator • Audio Para EQ • Audio Play • Audio Render • Audio Spectrum • Audio Stream In • Experimental:Audio Stream In • Audio Stream Out • Beat • Bind • BlackTrax • Blend • Blob Track • Bullet Solver • Clip Blender • Clip • Clock • Composite • Constant • Copy • Count • CPlusPlus • Cross • Cycle • DAT to • Delay • Delete • DMX In • DMX Out • Envelope • EtherDream • Event • Expression • Extend • Fan • Feedback • File In • File Out • Filter • Experimental:Filter • Experimental:FreeD • Function • Gesture • Handle • Helios DAC • Hog • Hokuyo • Hold • Import Select • In • Info • Interpolate • Introduction To CHOPs id • Inverse Curve • Inverse Kin • Join • Joystick • Keyboard In • Keyframe • Kinect Azure • Kinect • Lag • Laser • Leap Motion • Leuze ROD4 • LFO • Limit • Logic • Lookup • LTC In • LTC Out • Math • Merge • MIDI In • MIDI In Map • MIDI Out • Mouse In • Mouse Out • NatNet In • Noise • Null • Object • Oculus Audio • Oculus Rift • OpenVR • OSC In • OSC Out • Out • Override • Panel • Pangolin • Parameter • Pattern • Perform • Experimental:Phaser • Pipe In • Pipe Out • PosiStageNet • Pulse • RealSense • Record • Rename • Render Pick • Reorder • Replace • Resample • S Curve • Scan • Script • Select • Sequencer • Serial • Shared Mem In • Shared Mem Out • Shift • Shuffle • Slope • SOP to • Sort • Speed • Splice • Spring • Stretch • Stype • Switch • Sync In • Sync Out • Tablet • Time Slice • Timeline • Timer • TOP to • Touch In • Touch Out • Trail • Transform • Transform XYZ • Trigger • Trim • Warp • Wave • Experimental:WrnchAI • ZED

An Operator Family which operate on Channels (a series of numbers) which are used for animation, audio, mathematics, simulation, logic, UI construction, and many other applications.

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 only 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.

samples-per-second of a CHOP. Each CHOP in your network has a sample rate, whether it is used or not. The overall timeline has a "frame rate", which is the number of animation frames per second, generally your monitor display frequency.

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 command Script, 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/torus1, a node called torus1 in a component called geo1. The path / is called Root. To refer instead to a filesystem folder, directory, disk file or http: address, see Folder.

Parameters in TouchDesigner are an operator's settings (numbers, menus, flags, strings, paths) which the user can alter. Parameters for any operator can be opened by right-clicking on the operator and selecting "Parameters..." A currently selected operator's parameters can be viewed in a Network Editor by pressing the keyboard shortcut 'p'.

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