Constant CHOP
The Constant CHOP is the simplest CHOP — it outputs one or more channels with fixed, user-defined values that do not change over time. Think of it as a named variable or knob.
Key Parameters
| Parameter | Description |
|---|---|
| Name 0, 1, 2… | Channel names (e.g. r, g, b or speed) |
| Value 0, 1, 2… | The fixed numeric value for each channel |
Click the + button to add more name/value pairs.
Why Use It?
The Constant CHOP transforms a raw number into a named, wireable channel. This lets you:
- Feed a value into a Math CHOP pipeline without hardcoding it in expressions.
- Create a single source of truth — one Constant that multiple nodes reference, so you only need to update one place.
- Use it as a manual override by putting it in a
Switch CHOP.
Common Usage Patterns
Global speed control
Constant CHOP → chan: "speed", value: 1.0
→ [referenced by op('speed')['speed'] in multiple LFO/Noise CHOPs]
Change speed in one place, affect the whole network.
Colour constant
Constant CHOP
chan0: "r" = 0.2
chan1: "g" = 0.8
chan2: "b" = 0.5
→ Math CHOP → [drive RGB parameters of a Light or Material]
Combining with a null
A common pattern is:
Constant CHOP → Null CHOP (named e.g. CTRL_Speed)
The Null acts as a clean output point and makes references more stable if you swap out the Constant for an LFO or UI slider later.
Practical Example: Swappable Signal Source
Place a Constant and an LFO side-by-side, feed both into a Switch CHOP, and control which one is active with a parameter. This gives you a manual/auto toggle.
Differences from Just Typing a Number
| Typed in parameter | Constant CHOP | |
|---|---|---|
| Can drive multiple targets | ✗ (must copy value) | ✓ (one wire to many) |
| Can be automated later | Requires rewrite | Just swap in an LFO |
| Visible in network | ✗ | ✓ | | Named | ✗ | ✓ |
Common Gotchas
- The Constant CHOP’s value is not keyframeable by default — if you want animation, switch to an Animation CHOP or an LFO CHOP.
- When you export a Constant channel to a parameter, changing the parameter directly will stop working (the export overrides it).
Related Nodes
- LFO CHOP — time-varying signal
- (y-) Noise CHOP — random/organic signal
- Math CHOP — combine and remap constant values
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