IFC 4.3.1.0 (IFC4X3_ADD1)

8.12.3.1 IfcBlobTexture

8.12.3.1.1 Semantic definition

An IfcBlobTexture provides a 2-dimensional distribution of the lighting parameters of a surface onto which it is mapped. The texture itself is given as a single binary blob, representing the content of a pixel format file. The file format of the pixel file is given by the RasterFormat attribute and allowable formats are guided by where rule SupportedRasterFormat.

For interpretation of the texture nodes see IfcImageTexture definition.

8.12.3.1.2 Entity inheritance

8.12.3.1.3 Attributes

# Attribute Type Description
IfcSurfaceTexture (7)
1 RepeatS IfcBoolean

The RepeatS field specifies how the texture wraps in the S direction. If RepeatS is TRUE (the default), the texture map is repeated outside the [0.0, 1.0] texture coordinate range in the S direction so that it fills the shape. If RepeatS is FALSE, the texture coordinates are clamped in the S direction to lie within the [0.0, 1.0] range.

2 RepeatT IfcBoolean

The RepeatT field specifies how the texture wraps in the T direction. If RepeatT is TRUE (the default), the texture map is repeated outside the [0.0, 1.0] texture coordinate range in the T direction so that it fills the shape. If RepeatT is FALSE, the texture coordinates are clamped in the T direction to lie within the [0.0, 1.0] range.

3 Mode OPTIONAL IfcIdentifier

Mode shall hold the type of map this corresponds to, chosen from the following list: AMBIENT, NORMAL, EMISSIVE, METALLICROUGHNESS, OCCLUSION, SHININESS, SPECULAR, DIFFUSE.

If Mode is omitted, DIFFUSE is assumed.

4 TextureTransform OPTIONAL IfcCartesianTransformationOperator2D

The TextureTransform defines a 2D transformation that is applied to the texture coordinates. It affects the way texture coordinates are applied to the surfaces of geometric representation items. The 2D transformation supports changes to the size, orientation, and position of textures on shapes. Mirroring is not allowed to be used in the IfcCartesianTransformationOperator

5 Parameter OPTIONAL LIST [1:?] OF IfcIdentifier
IsMappedBy SET [0:?] OF IfcTextureCoordinate FOR Maps

Texture coordinates, either provided by a corresponding list of texture vertices to vertex-based geometric items or by a texture coordinate generator, that applies the surface texture to the surfaces of the geometric items.

UsedInStyles SET [0:?] OF IfcSurfaceStyleWithTextures FOR Textures

No description available.

Click to show 7 hidden inherited attributes Click to hide 7 inherited attributes
IfcBlobTexture (2)
6 RasterFormat IfcIdentifier

The format of the RasterCode often using a compression.

7 RasterCode IfcBinary

Blob, given as a single binary, to capture the texture within one popular file (compression) format. The file format is provided by the RasterFormat attribute.

Table 8.12.3.1.A

8.12.3.1.4 Formal propositions

Name Description
RasterCodeByteStream

The size of the raster code shall be a multiple of 8 bits.

BLENGTH(RasterCode) MOD 8 = 0
SupportedRasterFormat

Currently the formats of bmp, jpg, gif and pgn, shall be supported.

SELF.RasterFormat IN ['BMP', 'JPG', 'GIF', 'PNG']
Table 8.12.3.1.B

8.12.3.1.5 Formal representation

ENTITY IfcBlobTexture
 SUBTYPE OF (IfcSurfaceTexture);
	RasterFormat : IfcIdentifier;
	RasterCode : IfcBinary;
 WHERE
	RasterCodeByteStream : BLENGTH(RasterCode) MOD 8 = 0;
	SupportedRasterFormat : SELF.RasterFormat IN ['BMP', 'JPG', 'GIF', 'PNG'];
END_ENTITY;

8.12.3.1.6 References

8.12.3.1.7 Changelog

8.12.3.1.7.1 IFC4

  • where rule, RasterCodeByteStream
  • where rule, SupportedRasterFormat
  • where rule, WR11
  • attribute RasterCode type, Changed from "boolean" to "IfcBinary"