Method IsClosed
- Namespace
- GeometryHelper.Geometry
- Assembly
- GeometryHelper.dll
IsClosed()
Checks whether the boundary closes without gaps, using the default tolerance.
public bool IsClosed()Returns
IsClosed(Tolerance)
Checks whether the boundary closes without gaps, within a tolerance.
public bool IsClosed(Tolerance tolerance)Parameters
toleranceTolerance
Returns
Remarks
A closed surface has every stretch of every edge shared by an even number of faces. One face on a stretch is an open rim and three are a fin standing off the surface; two close it, and so do four where two blocks meet along an edge — watertight, and measuring and holding points as they should. Hole rims count as edges like any other, since in a closed body they are shared with the surface lining the cavity behind them.
Edges are first matched by their end points, through a spatial grid, which settles the usual body in time linear in its vertices. Only where that leaves an edge not used exactly twice are the edges matched by overlap along a line, stretch by stretch: a long edge beside two short ones — which merging coplanar faces and the booleans both leave behind — has no partner by its end points, and was called open, as was a body meeting itself along an edge.