8.12.3.19 IfcIndexedPolygonalTextureMap

8.12.3.19.1 Semantic definition

The IfcIndexedPolygonalTextureMap provides the mapping of the 2-dimensional texture coordinates to a set of polygonal bounded faces onto which it is mapped. It is used for mapping the texture to faces of an IfcPolygonalFaceSet. Such faces may have inner loops.

The TexCoords defined at supertype IfcIndexedTextureMap are a two-dimensional list of texture coordinates providing two parameter values for each indexed texture vertex. The set of TexCoordIndices provides the texture coordinates for the list of IfcIndexedPolygonalFace referred to via MappedTo.Faces. The texture coordinates at each IfcTextureCoordinateIndices correspond to the vertex points at the referenced IfcIndexedPolygonalFace. See also Figure A for further explanation.

Figure A shows how to use IfcIndexedPolygonalTextureMap to provide the texture and texture coordinates for IfcPolygonalFaceSet.

Instantiation diagram showing the use of _IfcIndexedPolygonalTextureMap_ — Figure A — Use of _IfcIndexedPolygonalTextureMap_

8.12.3.19.2 Entity inheritance

8.12.3.19.3 Attributes

#	Attribute	Type	Description
IfcTextureCoordinate (1)
1	Maps	LIST [1:?] OF IfcSurfaceTexture	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.
IfcIndexedTextureMap (2)
2	MappedTo	IfcTessellatedFaceSet	Reference to the IfcTessellatedFaceSet to which it applies the texture map.
3	TexCoords	IfcTextureVertexList	Indexable list of texture vertices.
Click to show 3 hidden inherited attributes Click to hide 3 inherited attributes
IfcIndexedPolygonalTextureMap (1)
4	TexCoordIndices	SET [1:?] OF IfcTextureCoordinateIndices	Set of texture coordinate indices for polygonal faces with and without inner loops.

Table B

8.12.3.19.4 Formal representation

ENTITY IfcIndexedPolygonalTextureMap
SUBTYPE OF (IfcIndexedTextureMap);
TexCoordIndices : SET [1:?] OF IfcTextureCoordinateIndices;
END_ENTITY;