Bind parameter to channel
bind_to_channelDrive one or more TouchDesigner node parameters from a CHOP channel in real time, with optional attack/release smoothing for clean envelope following.
Instructions
Drive one or more node parameters from a CHOP channel by expression — the link that makes a visual react. Point it at an audio_features channel (bass/mid/treble/level) or a tempo_sync channel (ramp/pulse/beat) with a scale and offset, and each target parameter tracks that signal live. This is how you wire extract_audio_features / create_tempo_sync into a visual system. Optionally add attack/release smoothing (in seconds) — or a single smooth time — to insert a Lag CHOP between the channel and the parameter so reactivity follows a clean envelope instead of flickering on raw audio (e.g. a fast attack + slow release for a punchy hit that decays smoothly).
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| targets | Yes | Parameters to drive, each written as 'nodePath.parName' (e.g. '/project1/sys/transform1.scale'). Each is switched to expression mode so it tracks the channel live. | |
| source_chop | Yes | Path of the CHOP that carries the driving channel (e.g. an audio_features Null). | |
| channel | Yes | Channel name to read from the source CHOP (e.g. 'bass', 'level', 'ramp', 'pulse'). | |
| scale | No | Multiply the channel value (mapping gain). | |
| offset | No | Add to the scaled value (mapping offset). | |
| attack | No | Smoothing rise time in seconds — how slowly the bound value follows the channel UP. 0 = instant (no smoothing on the way up). A small attack with a larger release gives a snappy hit that decays smoothly (envelope follow). | |
| release | No | Smoothing fall time in seconds — how slowly the bound value follows the channel DOWN. 0 = instant (no smoothing on the way down). Set release > attack to remove flicker while keeping transients punchy. | |
| smooth | No | Convenience: symmetric smoothing time in seconds applied to BOTH rise and fall (sets attack=release=smooth). Use this for simple low-pass-style de-jitter; use attack/release separately for an envelope follower. | |
| smoothing_container | No | Where to create the Select+Lag smoothing CHOPs when smoothing is active; defaults to the first target's parent network. Ignored when no smoothing is requested. |