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The SEDRIS Data Representation Model
APPENDIX A - Classes Geometry Volume |
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An instance of this DRM class is a three-dimensional <Geometry Topology> instance used to represent an enclosed region of space that is bounded by two or more <Geometry Face> instances.
Consider a <Polyhedron> representing a building. It has a collection of <Polygon>s, which define its geometric shape; an associated <Geometry Volume>, which defines its topological relationships; a <Classification Data> component that classifies it as an ECC_BUILDING; <Property Value> components that describe its characteristics, such as material composition, and a <Label> that identifies it as "The Empire State Building".
<Geometry Volume> instances are required only when the geometry topology level is five.
Yes. <Geometry Volume> instances must always have closed external boundaries (defined by their component <Polygon>s), and their interiors must be fully connected. At geometry topology level 5, the interiors of <Geometry Volume> instances may not intersect or overlap one another, and <Geometry Volume> instances may meet only along one or more common <Geometry Face> instances.
Yes. <Geometry Volume> instances may exist at any geometry topology level. At geometry topology level 5, the collection of <Geometry Volume> instances must exhaustively and exclusively partition the 3-dimensional topological space, such that exactly two <Geometry Volume> instances shall be bounded by each <Geometry Face>.
If a given <Geometry Volume> has an association relationship with a <Geometry Edge> instance, that <Geometry Edge> instance is contained within the <Geometry Volume>.
The <Geometry Face> instances that border a given <Geometry Volume> instance indicate the relationship by their association to the <Geometry Volume>. The converse of this relationship is that between <Geometry Volume> and <Geometry Face>.
If a given <Geometry Volume> has an association relationship with a <Geometry Node> instance, that <Geometry Node> instance is contained within the <Geometry Volume>.
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