Assembly Spline – Distribution

Generates mesh distribution patterns (random or round-robin) for assembly spline component placement, with probability weighting and variation support.

Module Info

Public Functions

Component Group Structure

componentGroup = {
  mesh = {
    id = "fence_post",
    meshPath = "/props/fence/post.dae",
    randomWeight = 1.0
  },
  randomWeight = 1.0,              -- base component weight
  variations = {
    { id = "fence_post_alt", meshPath = "/props/fence/post_alt.dae", randomWeight = 0.5 },
  }
}

Algorithm Details

Random Distribution

1. Collects all enabled components (base + variations) using mol.getRigidEnabled / mol.getBridgeEnabled
2. Normalises randomWeight values to sum to 1.0
3. For each placement, samples a component using cumulative probability
4. Returns array of mesh paths

Round-Robin Distribution

1. Collects all enabled components
2. Cycles through them sequentially for each placement
3. Returns array of mesh paths

Internal State

Pre-allocated arrays are reused across calls for performance:

Usage Example

local dist = require('editor/assemblySpline/distribution')

-- Compute distribution maps for all rigid and bridge components
local rigidMaps, bridgeMaps = dist.computeMeshMap(molecule, numPlacements, mySpline)

Functions

computeMeshMap(molecule, numPlacements, spline)

Computes component distribution maps for all rigid and bridge components in the molecule. Uses random or round-robin distribution based on each component group's isRandom flag. Bridge maps have numPlacements - 1 entries (one per adjacent molecule pair).

• molecule (table) - Molecule structure with rigids and bridges arrays
• numPlacements (number) - Number of molecule placement positions along the spline
• spline (table) - The assembly spline (used to check enabled states)

Returns: rigidMaps (table), bridgeMaps (table) - Indexed arrays of mesh path arrays per component group

See Also

• Assembly Spline - Main tool
• Assembly Spline Import - Scene import