# 8.20.3.5 IfcEdgeCurve

## 8.20.3.5.1 Semantic definition

An IfcEdgeCurve defines two vertices being connected topologically including the geometric representation of the connection.

Informal Propositions:

1. The domain of the edge curve is formally defined to be the domain of its edge geometry as trimmed by the vertices. This domain does not include the vertices.
2. An edge curve has non-zero finite extent.
3. An edge curve is a manifold.
4. An edge curve is arcwise connected.
5. The edge start is not a part of the edge domain.
6. The edge end is not a part of the edge domain.
7. Vertex geometry shall be consistent with edge geometry.

## 8.20.3.5.4 Formal representation

ENTITY IfcEdgeCurve
SUBTYPE OF (IfcEdge);
EdgeGeometry : IfcCurve;
SameSense : IfcBoolean;
END_ENTITY;