API Reference > geometry-core > Polyface > PolyfaceQuery > isPolyfaceManifold isPolyfaceManifold MethodStatic Test edges pairing in source mesh. for allowSimpleBoundaries === false true return means this is a closed 2-manifold surface for allowSimpleBoundaries === true true means this is a 2-manifold surface which may have boundary, but is still properly matched internally. Any edge with 3 ore more incident facets triggers false return. Any edge with 2 incident facets in the same direction triggers a false return. isPolyfaceManifold(source: Polyface, allowSimpleBoundaries: boolean = false): boolean Parameter Type Description source Polyface allowSimpleBoundaries boolean Returns - boolean Defined in core/geometry/src/polyface/PolyfaceQuery.ts Line 259 Last Updated: 13 June, 2024