Shapes and spline utilities

Footprints repeat: the L, the U, the rectangle with a notch. The Shape Library stores them once so drawing one is a click, and the spline commands handle the rest of the everyday path surgery - mirroring, flattening, merging, repairing.

Shape Library

Each shape entry has a stable Shape ID, Display Name, Description, Category, Closed Loop flag, read-only built-in status, and one or more loops of local points. Built-in shapes include common rectangles, circles, and building footprints; plugin Basic Shape meshes can also be imported as shape entries.

Use the Spline Architect menu to:

• Apply Shape to replace an active actor/path. Architect Mode applies only single-loop entries to the active path.
• Save Shape from selected spline actors for later reuse.
• Import Shapes from compatible Static Mesh boundary data.

Multi-loop shapes are valid for actor-level application and can drive Multi Spline polygon operations.

Import Shape From Mesh... extracts the boundary loops of a Static Mesh and saves them as a shape. Selecting several meshes imports them all in one pass: names come from the source meshes with no prompt, meshes already imported are skipped, genuine name collisions are suffixed, and one notification summarises what was imported, skipped, and had no usable outline. A single-file import still prompts for a name as before.

Spline menu commands

Command	Result
Spline to Selected	Copies or assigns a selected spline source to a compatible actor.
Merge Spline Actors	Combines selected compatible paths into one actor with multiple spline components.
Break to Spline	Creates ordinary spline actor data from generated/selected Spline Architect paths.
Mirror X / Mirror Y	Commits a geometric mirror to authored points.
Flatten	Sets points to a common elevation.
Reverse	Reverses point order and winding.
Gridify	Snaps points to the actor's Grid Size.
Reset Transform / Center Transform	Normalizes or recenters actor transforms while preserving world-space path geometry.
Clean Invalid / Delete Invalid	Finds and removes invalid plugin actors or connections after review.
Select Roots / Filter Roots / Select Connected	Navigates connected Wall/Building hierarchies.

Multi-spline polygon operations

Wall and Building actors can generate each spline independently or combine closed loops by Union. Because polygon work is solved in 2D, Union Z Mode decides how Z is restored: Flatten to Min Z, Average Z, Nearest Point, or Surface Trace.

For symmetry exploration, prefer generation-only Mirror Mode. When the result becomes authored topology, use Apply Mirror to Spline. This avoids permanently doubling point edits before the design is settled.