Prepare a labelled surface for parcel rendering — prepare_surface

Precomputes the per-geometry quantities used by [render_surface_parcels()]: outward vertex normals, a normalized anatomical underlay, and smoothed label memberships that let parcel boundaries follow smooth curves through mesh triangles instead of stair-stepping along triangle edges. Reuse the result across cameras and value maps.

Usage

prepare_surface_parcels(
  geometry,
  labels,
  anatomy_metric = NULL,
  cortex_mask = NULL,
  boundary_smooth = 3L
)

Arguments

geometry: Display `SurfaceGeometry` (typically inflated).
labels: Integer parcel label per vertex; 0 marks the medial wall.
anatomy_metric: Optional sulcal-depth or curvature value per vertex, larger on gyri. `NULL` gives a neutral underlay.
cortex_mask: Optional logical per vertex; `FALSE` vertices are treated as medial wall. Defaults to `labels != 0`.
boundary_smooth: Laplacian iterations applied to label memberships. 0 gives piecewise-linear boundaries through triangle edge midpoints.

Value

A `surface_parcel_prep` object.