IfcMaterialDefinitionRepresentation

Semantic definitions at the entity

Entity definition

IfcMaterialDefinitionRepresentation defines presentation information relating to IfcMaterial. It allows for multiple presentations of the same material for different geometric representation contexts.

NOTE The IfcMaterialDefinitionRepresentation is currently only used to define presentation information to material used at element occurrences, defined as subtypes of IfcElement, or at element types, defined as subtypes of IfcElementType. The IfcMaterial is assigned to the subtype of IfcElement, or IfcElementType using the IfcRelAssociatesMaterial relationship (eventually via other material related entities IfcMaterialLayerSetUsage, IfcMaterialLayerSet, IfcMaterialLayer, or IfcMaterialProfileSetUsage, IfcMaterialProfileSet, IfcMaterialProfile).

The IfcMaterialDefinitionRepresentation can apply

different presentation styles for different representation contexts, for example, a different style for sketch view, model view or plan view, or for different target scales,
for each representation context is can apply curve style, fill area style (hatching), symbol, text and surface style.

HISTORY New entity in IFC2x3.

IFC2x3 CHANGE The entity IfcMaterialDefinitionRepresentation has been added. Upward compatibility for file based exchange is guaranteed.

IFC4 CHANGE The assignment of curve, surface and other styles to an IfcStyledItem has been simplified by IfcStyleAssignmentSelect. The use of intermediate IfcPresentationStyleAssignment is deprecated.

Use definition

	As shown in Figure 435, the presentation assignment can be specific to a representation context by adding one and more IfcStyledRepresentation's. Each of them includes a single IfcStyledItem with exactly zero or one style for either curve, fill area, surface, text or symbol style that is applicable.
Figure 435 — Material definition representation

Attribute definitions

#	Attribute	Type	Cardinality	Description	G
4	RepresentedMaterial	IfcMaterial		Reference to the material to which the representation applies.	X

Formal Propositions

Rule	Description
OnlyStyledRepresentations	Only representations of type IfcStyledRepresentation should be used to represent material through the IfcMaterialRepresentation.

Inherited definitions from supertypes

Entity inheritance

Attribute inheritance

#	Attribute	Type	Cardinality	Description	G
IfcProductRepresentation
1	Name	IfcLabel	?	The word or group of words by which the product representation is known.	X
2	Description	IfcText	?	The word or group of words that characterize the product representation. It can be used to add additional meaning to the name of the product representation.	X
3	Representations	IfcRepresentation	L[1:?]	Contained list of representations (including shape representations). Each member defines a valid representation of a particular type within a particular representation context.	X
IfcMaterialDefinitionRepresentation
4	RepresentedMaterial	IfcMaterial		Reference to the material to which the representation applies.	X

Formal representations

XML Specification

 <xs:element name="IfcMaterialDefinitionRepresentation" type="ifc:IfcMaterialDefinitionRepresentation" substitutionGroup="ifc:IfcProductRepresentation" nillable="true"/>

 <xs:complexType name="IfcMaterialDefinitionRepresentation">

  <xs:complexContent>

   <xs:extension base="ifc:IfcProductRepresentation"/>

  </xs:complexContent>

 </xs:complexType>

EXPRESS Specification


ENTITY IfcMaterialDefinitionRepresentation

 SUBTYPE OF (IfcProductRepresentation);

  RepresentedMaterial : IfcMaterial;

 WHERE

  OnlyStyledRepresentations : SIZEOF(QUERY(temp <* Representations | 

  (NOT('IFCREPRESENTATIONRESOURCE.IfcStyledRepresentation' IN TYPEOF(temp)))

)) = 0;
END_ENTITY;

 EXPRESS-G diagram

	Materialdefinition - Repräsentation
	Material Definition Representation
	Représentation de définition de matériau