Switch

The Switch node gates growth flow.
It chooses between multiple input graphs based on conditions evaluated per internode.

Think of it as an if/else statement for growth recipes: if an attribute or map passes a test, the branch continues through one path; otherwise it follows another.

Concept

Why Switch?

• To build state-driven growth (buds → shoots → flowers).
• To gate branches by environmental conditions (e.g. prune above a certain height).
• To introduce variation (random or mapped switches).
• To make recipes adaptive without duplicating graphs.

Inputs

Input 0 — Graph A
When the switch evaluates to false evaluate this graph.

Input 1 — Graph B
When the switch evaluates to true evaluate this graph.

Output — Graph
The merged Apex graph to be passed down the network.

Parameters

• Conditions (conditions)
  A multiparm list of gates. Each condition compares a chosen attribute against a constant, another attribute, or a mapping.
  • Attribute – which graph attribute to read (e.g. height, u, age).
  • Condition – the operation: >=, <=, ==, etc.
  • Threshold / Attribute / Map – the value to compare against. Can be:
    • Float – fixed number.
    • Attrib – another attribute.
    • Map – mapping chain.
• Snippet Condition (graph_snippet_condition)
  Advanced mode. Write inline VEX to decide routing (e.g. f@height > 5).

Attributes

Switch does not emit new attributes, but it consumes existing ones for gating:

• Typical: height, u, generation, age, random.
• Any custom attributes created by Wrangle or mappings are also valid.

Workflow

1. Insert a Switch node into your growth recipe.
2. Connect alternative subgraphs to its extra inputs.
3. Define one or more conditions.
4. Each internode is tested; the first passing condition determines which branch graph it takes.

📌 No conditions matched? The internode takes the default path (the last input, if connected).

How-tos

Threshold gating

Route branches only if they exceed a certain height:

Attribute: height
Condition: >= float
Threshold: 5.0

Attribute vs Attribute

Only fork when internode width exceeds length:

Attribute A: width
Condition: >= attrib
Attribute B: internode_length

Map-driven switch

Drive conditions with a mapping chain:

Attribute: height
Condition: >= map
Map: ../map1

VEX condition

Use inline VEX for custom logic:

f@height > 5 && i@generation < 3

Applications

• Stage transitions – control when a bud turns into a flower.
• Environmental pruning – stop growth above certain heights or densities.
• Random variation – shuffle different subgraphs with a noise-based attribute.
• Hybrid recipes – combine Grow, Repeat, and Switch to create adaptive structures.

See also

• Grow – builds internodes
• Repeat – iterative growth
• Split – unconditional branching
• Wrangle – generate attributes to drive Switch conditions