td-building

TouchDesigner building — AI assistant skill

You are helping someone build a TouchDesigner (TD) network. TD is node-graph creative-coding software by Derivative. Operator families: TOP (images), CHOP (channels/animation), SOP (geometry), POP (particles, 2023+), DAT (data/text), COMP (containers/3D).

Philosophy

• TD is pull-based: nodes cook only when their output is requested. Never force-cook unless you need a snapshot.
• Prefer CHOPs + expressions over Python for time-varying values.
• Always look up operator/parameter names before coding (use td_docs_search / td_docs_parameter). Never guess a parameter code.
• Wrap mutations in ui.undo for a single Ctrl+Z revert.

Operator families

• TOP — texture/image operators (Blur, Noise, Level, Feedback, GLSL).
• CHOP — channel/animation operators (LFO, Audio Device In, Math, Filter).
• SOP — CPU geometry (Box, Sphere, Transform, Noise).
• POP — GPU particles, build 2023.10000+.
• DAT — data/text (Table, Text, Script, Execute, Web Client).
• COMP — networks/UI (Container, Geometry, Camera, Light, Render).

Critical conventions

• Parameter identifiers are lowercase, no spaces: par.file, not filename.
• op('x').par.file = 'path' — the classic Movie File In TOP example.
• A CHOP→TOP takes its source via the chop parameter, not an input wire.
• Geometry COMP's create type is geometryCOMP, not geoCOMP.
• Feedback TOP needs an input wired to initialize its buffer.
• GLSL TOP uniforms go on the Vectors page (runtime), not Constants page (compile-time only, fails silently).

Python essentials

op('noise1')                 # relative path
op('/project1/noise1')       # absolute path
op('x').par.roughness.eval() # current value
op('x').par.roughness = 0.5  # direct set
op('x').par.roughness.expr = "me.time.seconds"
with ui.undo: op('x').par.value0 = 1  # undo-safe mutation
op('x').store('key', value)  # persistent per-node state
op('x').fetch('key')