 | Liste von Indizes für Texturen auf Dreiecken |
 | Indexed Triangle Texture Map |
| Item | SPF | XML | Change | Description | IFC2x3 to IFC4 |
|---|---|---|---|---|
| IfcIndexedTriangleTextureMap | ADDED | IFC4 Addendum 1 | ||
| IfcIndexedTriangleTextureMap | ||||
| TexCoordIndex | MODIFIED | Type changed from INTEGER to IfcPositiveInteger. |
The IfcIndexedTriangleTextureMap provides the mapping of the 2-dimensional texture coordinates to the surface onto which it is mapped. It is used for mapping the texture to triangles of the IfcTriangulatedFaceSet.
The IfcIndexedTriangleTextureMap defines an index into an indexed list of texture coordinates. The TexCoordIndex is a two-dimensional list, where
The TexCoords defined at supertype IfcIndexedTextureMap are a two-dimensional list of texture coordinates provided by two parameter values. Each index of the second dimension list of TexCoordIndex points to a texture vertex in TexCoords.
Figure 395 shows the use of IfcTriangulatedFaceSet with textures.
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Figure 395 — Indexed triangle texture map |
Figure 396 illustrates an IfcTriangulatedFaceSet represented by
IfcTriangulatedFaceSet.CoordIndex: ((1,6,5), (1,2,6), (6,2,7), (7,2,3),
(7,8,6), (6,8,5), (5,8,1), (1,8,4), (4,2,1), (2,4,3),
(4,8,7), (7,3,4))
IfcCartesianPointList.CoordList: ((0.,0.,0.), (1.,0.,0.),
(1.,1.,0.), (0.,1.,0.), (0.,0.,2.), (1.,0.,2.), (1.,1.,2.),
(0.,1.,2.))
IfcIndexedTriangleTextureMap.TexCoordsIndex: ((1 4 3), (1 2 4), (3 1 4), (4 1 2), (8 7 6), (6 7 5), (4 3 2), (2 3 1),
(5 8 7), (8 5 6), (2 4 3), (3 1 2))
IfcTextureVertexList.TexCoordsList: ((0. -0.5), (1. -0.5), (0. 1.5), (1. 1.5),
(0. 0.), (0. 1.), (1. 0.), (1. 1.))
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Figure 396 — Indexed triangle texture map geometry |
HISTORY New entity in IFC4.
| # | Attribute | Type | Cardinality | Description | G |
|---|---|---|---|---|---|
| 4 | TexCoordIndex | IfcPositiveInteger | ? L[1:?] L[3:3] | Index into the IfcTextureVertexList for each vertex of the triangles representing the IfcTriangulatedFaceSet. | X |
| # | Attribute | Type | Cardinality | Description | G |
|---|---|---|---|---|---|
| IfcPresentationItem | |||||
| IfcTextureCoordinate | |||||
| 1 | Maps | IfcSurfaceTexture | L[1:?] | Reference to the one (or many in case of multi textures with identity transformation to geometric surfaces) subtype(s) of IfcSurfaceTexture that are mapped to a geometric surface by the texture coordinate transformation. | X |
| IfcIndexedTextureMap | |||||
| 2 | MappedTo | IfcTessellatedFaceSet | Reference to the IfcTessellatedFaceSet to which it applies the texture map. | X | |
| 3 | TexCoords | IfcTextureVertexList | Indexable list of texture vertices. | X | |
| IfcIndexedTriangleTextureMap | |||||
| 4 | TexCoordIndex | IfcPositiveInteger | ? L[1:?] L[3:3] | Index into the IfcTextureVertexList for each vertex of the triangles representing the IfcTriangulatedFaceSet. | X |
<xs:element name="IfcIndexedTriangleTextureMap" type="ifc:IfcIndexedTriangleTextureMap" substitutionGroup="ifc:IfcIndexedTextureMap" nillable="true"/>
<xs:complexType name="IfcIndexedTriangleTextureMap">
<xs:complexContent>
<xs:extension base="ifc:IfcIndexedTextureMap">
<xs:attribute name="TexCoordIndex" use="optional">
<xs:simpleType>
<xs:restriction>
<xs:simpleType>
<xs:list itemType="ifc:IfcPositiveInteger"/>
</xs:simpleType>
<xs:minLength value="3"/>
</xs:restriction>
</xs:simpleType>
</xs:attribute>
</xs:extension>
</xs:complexContent>
</xs:complexType>
ENTITY IfcIndexedTriangleTextureMap
SUBTYPE OF (IfcIndexedTextureMap);
TexCoordIndex : OPTIONAL LIST [1:?] OF LIST [3:3] OF IfcPositiveInteger;
END_ENTITY;
EXPRESS-G diagram
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