TouchDesigner

Personal knowledge base for rapid re‑entry into TouchDesigner after long breaks.

TouchDesigner uses node‑based workflows where data flows through operators (OPs) that cook when needed.

• Official Website

• Interactive and Immersive HQ Tutorial channel

• O|I toggle: Enables/disables cooking globally (useful for heavy networks).
• Perform Mode: Toggle with F1. Used to run the system fullscreen. ESC returns to editing mode.
• Palette: Contains ready‑made components; double‑click to inspect internal networks.
• Operator Snippets: Help → Operator Snippets shows practical examples for most OPs.

• Viewers can be toggled Active (button bottom-right).

This allows panning/zooming inside the viewer without affecting the OP’s output.

• Panes can be split using ALT + [ (vertical) or ALT + ] (horizontal).
• The ▼ button on each pane opens more panes; the ↓ menu switches pane types (Network Editor, Geometry View, etc.).
• ALT + Z: Close pane under mouse.

• Left Click + drag: Move operator or pan when clicking empty space.
• Right Click + drag: Selection box.
• Mouse Wheel: Zoom.

(Shortcuts only work with the cursor in the Network Editor, and are case sensitive - careful with CAPS LOCK).

• TAB: Open Operator Create Menu (type in name to highlight)
• I: Dive inside a network. (also mouse wheel on it but clunky)
• U: Move up a level.
• H: Frame/home network.
• P: Toggle Parameters window.

• TOP: TEXTURE OPERATOR - Purple - 2D raster graphics
• CHOP: CHANNEL OPERATOR - Green - channels, numeric/time data, signal, communication,
• DAT: DATA OPERATOR - Pink - tables, strings, scripting
• SOP: SURFACE OPERATOR - Blue - Procedural 3D geometry
• COMP: COMPONENT OPERATOR - Grey - components, UI, 3D rendering
• MAT: MATERIAL OPERATOR - Yellow - materials, shaders

Dark-colored OPs are generators.

• Data flows left → right.
• Cooking occurs when dependent OPs need updated data.
• Animated noodles = cooking
• Static noodles = cached.
• Heavy cooking sources:
  • Full-res TOP chains
  • CHOPs with large sample counts
  • SOP deformers

Use nulls, selects, Resolution TOP, and Cache Select to avoid unnecessary cooking.

• Networks behave like Unix-style folders.
• Path bar shows current location.
• Double-click a COMP to see its internal network.

• Display flag = viewer preview.
• Render flag = included in rendering.
• Middle-click → info popup.
• “?” in parameter window → operator wiki page.

Even though the operators have 3D Previews, behind the scenes it is just data being visualized differently.

Viewers can be toggled Active with the button on the bottom right. This locks their position and enables to move the content around in the preview panel to highlight details of its processing. This does not affect its output.

MIDDLE CLICK on an operator opens the info dialog for that operator.

For each Operator hitting the ? button in the parameter window will open up the wiki page for that operator.

From the top menu Help > Operator Snippets opens up a floating window with many examples and notes on each operator and how to use them.

The Palette also bundles a list of “premade” components that can be drag & dropped into the network. Double-clicking on them will open up their internal networks to understand how they are built.

Every node has parameters that can be manually controlled, tied to UI, scripted, etc.

Right click on a node gives the option to open a floating parameter window.

When editing a parameter (e.g. speed on a moviefilein) MIDDLE MOUSE click and hold on the value will open a hover menu where the increment can be changed. While holding, when selecting an increment, sliding left and right will decrement/increment the value by the given increment. (Also works with a LEFT CLICK and hold but the hold is a little longer).

When a parameter has two values that you would like to increase/decrease equally this technique can be applied on the name of the parameter.

Rendering is done in a Render TOP.

Basic setup involves the 3D COMPS Cameras, Geometry and Light to bring the SOP chain operating on the CPU to the Rendering pipeline operating on the GPU and rasterize the content.

Add In SOPS in the Geometry op to send a chain of SOPS into it.

The display and render flags tell the rest of the network whether the node should be used in the rendering process and displayed in the viewer.

You can also take the output of your last (preferably null) operator in the SOP chain and right click > COMP > Geometry to automate a lot of the process.

You can put multiple things in a geometry comp with the display flag ON but it's best practice to keep just one item per geometry to have a cleaner network.

This operator calculates the motion vectors inside a video stream and codes it to the Red and Green channels.

This converts video streams into usable data for interactivity.

The data can be plugged into particle systems, fluid systems or any other creative content that accept data as input to react upon.

Output is done by using the Window COMP.

You can open as a separate window or in perform mode.

Tweak the Monitor, Opening Size and Toggle the Borders parameters.

Texturing is done with MAT operators and by sending things into the Color map property.

When creating a network of nodes, add null operators at strategic checkpoints. This way you can reference these null “checkpoints” everywhere else in your project and if anything has to change prior to the checkpoint the reference is still valid.

TOPs have a display flag at the bottom right which can be turned on to toggle a preview in the background of the network editor.

Use Select CHOPs to extract different channels from your other CHOPS to use them in the network.

• Select the CHOP and toggle the display with the + in the bottom right
• Select the TOP to link to parameter
• Drag & drop from the CHOP into the parameter
• Select Reference type (Most of the time it's CHOP Reference

You can also drag an entire CHOP into a CHOP to TOP operator to reference it.

COMP Buttons and sliders can be connected to Null operators to toggle them into run mode and handily display their output.

It's good practice to work in lower resolutions until you need to up the resolution with a Resolution TOP.

When using source loops into TOP Fx chains it's handy to pass them through a Resolution TOP and lower them down to half res to improve performance.

• absTime.frame will use the frame count to increment the parameter this expression is used on. Use math expression behind such as * 0.5 to slow down (or speed up)
• absTime.seconds like the above but slower
• me.digits will return the digit (auto incremented) in the operator name. You can associate it with a math expression such as * -5 to automatically increment or decrement a parameter as you copy/paste (useful for Cache Select building a trail effect for example).

Be wary of the frame count when using the Cache TOP as it is essentially what uses the most GPU memory.

It's best to use a Cache Select TOP rather than using the Output Index of the Cache TOP. They will have very small cook times and be totally free in terms of GPU memory as they will reference the images that are already in memory through the Cache TOP.

Use the Reorder top in conjunction with Cache and Cache select to create some nice RGB trailing effects

When working with instancing take care that the length match. For example if your SOP null has 40 points, then the CHOP you use on it should have 40 samples.

Instancing is done in the Geometry Comp under the tab of the same name. Reference another SOP in there and play around with the points.

Repetition of small processes (as basic as drawing a circle at every point of a circle) can make some very rich designs.

Overlapping content also enriches designs.