4.8.2.2 Box Geometry

Elements may have a simplified 'Box' representation describing the dimensions of the smallest box bounding the object. Such representation may be used for more efficient spatial indexing or hit-testing.

The representation identifier and type and the only allowed single representation item of the 'Box' representation are:

NOTE  The specification does not determine the method by which the bounding box has to be created. If such a method need to be prescribed the definition has to be established by model view definitions or implementer agreements.

Figure 68 illustrates an instance diagram.

Box GeometryIfcProductIfcProductDefinitionShapeIfcShapeRepresentationIfcGeometricRepresentationContextIfcLabelIfcLabelIfcBoundingBox

Figure 68 — Box Geometry

mvdXML Specification
<?xml version="1.0"?>
<ConceptTemplate xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" uuid="b942ceb1-b818-4683-871b-9c979fa34dd5" name="Box Geometry" status="sample" applicableSchema="IFC4" applicableEntity="IfcProduct">
  <Rules>
    <AttributeRule AttributeName="Representation">
      <EntityRules>
        <EntityRule EntityName="IfcProductDefinitionShape">
          <AttributeRules>
            <AttributeRule AttributeName="Representations">
              <EntityRules>
                <EntityRule EntityName="IfcShapeRepresentation">
                  <AttributeRules>
                    <AttributeRule AttributeName="ContextOfItems">
                      <EntityRules>
                        <EntityRule EntityName="IfcGeometricRepresentationContext" />
                      </EntityRules>
                    </AttributeRule>
                    <AttributeRule RuleID="Identifier" AttributeName="RepresentationIdentifier">
                      <EntityRules>
                        <EntityRule EntityName="IfcLabel">
                          <Constraints>
                            <Constraint Expression="Identifier[Value] = 'Box'" />
                          </Constraints>
                        </EntityRule>
                      </EntityRules>
                    </AttributeRule>
                    <AttributeRule RuleID="Type" AttributeName="RepresentationType">
                      <EntityRules>
                        <EntityRule EntityName="IfcLabel">
                          <Constraints>
                            <Constraint Expression="Type[Value] = 'BoundingBox'" />
                          </Constraints>
                        </EntityRule>
                      </EntityRules>
                    </AttributeRule>
                    <AttributeRule AttributeName="Items">
                      <EntityRules>
                        <EntityRule EntityName="IfcBoundingBox" />
                      </EntityRules>
                    </AttributeRule>
                  </AttributeRules>
                </EntityRule>
              </EntityRules>
            </AttributeRule>
            <AttributeRule AttributeName="Name" />
            <AttributeRule AttributeName="Description" />
          </AttributeRules>
        </EntityRule>
      </EntityRules>
    </AttributeRule>
  </Rules>
</ConceptTemplate>

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