Definition

A <Feature Volume> instance FV has the following relationship with its associated <Feature Edge> instances, if any exist. At any feature topology level, if FV is associated with any <Feature Edge> instance FE, then FE shall lie completely within the external shell of FV, if any, and shall NOT lie within any of the internal shells of FV, if any. Conversely, if a <Feature Edge> instance FE lies within the boundaries of FV, then FE shall be associated with FV. If no <Feature Edge> instances lie within its boundaries, FV shall not be associated with any <Feature Edge> instances.

A <Geometry Volume> GV has the following relationship with its associated <Geometry Edge> instances, if any exist. At any geometry topology level, if GV is associated with any <Geometry Edge> instance GE, then GE shall lie completely within the interior of GV. Conversely, if a <Geometry Edge> instance GE lies completely within the interior of GV, then GE shall be associated with GV. If no <Geometry Edge> instances lie completely within its interior, GV shall not be associated with any <Geometry Edge> instances.

Rationale

The association between <Feature Edge> and <Feature Volume> implements a containment relationship. This topological relationship must be consistent, and must be consistent with the geometric representation of these objects.

The association between <Geometry Edge> and <Geometry Volume> implements a containment relationship. This topological relationship must be consistent, and must be consistent with the geometric counterparts of these objects.

Example

1. Consider a <Feature Edge> E1 that is "floating" within the interior of a <Feature Volume> V1. E1 is contained within V1, and V1 contains E1.

2. Consider a <Geometry Edge> E1 that is "floating" within the interior of a <Geometry Volume> V1. E1 is contained within V1, and V1 contains E1.

FAQs

If a <Feature Edge> is contained within the interior of a <Feature Volume>, must the <Feature Node> instances that bound that <Feature Edge> also be contained within the interior of that same <Feature Volume>?

No. The <Feature Node> instances that bound such a <Feature Edge> may be contained within the containing <Feature Volume>, or may be contained within the interior of one of the <Feature Face> instances that bound that <Feature Volume>, or may even be one of the <Feature Node> instances that bound one of the <Feature Edge> instances that in turn bound one of the <Feature Face> instances that bound that <Feature Volume>.

If a <Geometry Edge> is contained within the interior of a <Geometry Volume>, must the <Geometry Node> instances that bound that <Geometry Edge> also be contained within the interior of that same <Geometry Volume>?

No. The <Geometry Node> instances that bound such a <Geometry Edge> may be contained within the containing <Geometry Volume>, or may be contained within the interior of one of the <Geometry Face> instances that bound that <Geometry Volume>, or may even be one of the <Geometry Node> instances that bound one of the <Geometry Edge> instances that in turn bound one of the <Geometry Face> instances that bound that <Geometry Volume>.