Assembly Spline – Import

Imports existing scene objects (TSStatic groups) into assembly splines by analyzing positions, fitting curves, and reconstructing spline data with undo support.

Module Info

Constants

Public Functions

Import Pipeline

1. Backup: Saves all TSStatic objects' ID, name, position, rotation, scale, group before deletion
2. Position extraction: Collects world positions from component objects
3. Distance calculation: Computes inter-object distances for spacing
4. RDP simplification: Reduces point density using Ramer-Douglas-Peucker algorithm
5. Curve fitting: Uses fitPoly to generate smooth spline control points
6. Orientation detection: Votes on component alignment using tangent/binormal analysis
7. Spline creation: Creates a new assembly spline with imported nodes and width
8. Delayed update: Waits 2 frames for collision mesh rebuild before final update

Backup/Restore (Undo)

-- Backup structure per TSStatic
{
  id = number,
  name = string,
  shapeName = string,
  pos = vec3,
  rot = string,        -- "x y z w" rotation field
  scale = vec3,
  groupId = number      -- parent SimGroup ID
}

-- Restore recreates TSStatic objects with original properties
-- (restoreTSStatics is an internal function, not exported)

Orientation Voting

The importer determines component orientation by:

1. Computing tangent vectors along the spline
2. Calculating expected vs actual binormal directions
3. Voting across 4 rotation quadrants (0°, 90°, 180°, 270°)
4. Applying the winning rotation offset to all placements

Usage Example

local import = require('editor/assemblySpline/import')

-- Import selected scene objects into a new spline
local components = getSelectedTSStatics()
local spline = splineMgr.createNewSpline()
local backup = import.importFromSceneObjects(components, spline)

-- Undo: restore original objects
import.undoImport(backup)

Functions

validateToolCompatibleTSStatic(obj)

Checks if a TSStatic object has tool-compatible anchor points (names starting with nail.).

• obj (userdata) - A scene object to validate

Returns: boolean - true if the object is a TSStatic with at least one nail.* anchor point

convertTSStatics2AssemblySpline(collection)

Converts a collection of TSStatic object IDs into an assembly spline. Validates objects, reconstructs the assembly kit, fits a polyline, determines spacing/orientation, creates the spline, deletes originals, and commits to undo history.

• collection (table) - Array of TSStatic object IDs

Returns: nil

importFromPolygon(polygon)

Finds all TSStatic objects whose positions fall inside the given polygon and converts them to an assembly spline via convertTSStatics2AssemblySpline.

• polygon (table) - Array of vec3 points defining the selection polygon

Returns: nil

See Also

• Assembly Spline - Main tool
• Assembly Spline Distribution - Component distribution