8.12.3.1 IfcBlobTexture

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.

Toolbox specific implementations of the binary datatype may restrict the maximum length of the binary blob to capture the raster file content.

For interpretation of the texture nodes see IfcImageTexture definition.

New entity in IFC2x3. Data type of RasterCode has been corrected to BINARY.

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. IFC4-CHANGE New attribute replacing previous TextureType. IFC4.3.0.0-CHANGE Attribute has been repurposed to store the type of texture.
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	IFC4.3.0.0-DEPRECATION This attribute is deprecated and shall no longer be used.
	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. IFC4-CHANGE New attribute added at the end of the attribute list.
	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.B

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.C

8.12.3.1.5 Examples

Figure 8.12.3.1.A

Tessellation With Blob Texture

8.12.3.1.6 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;

8.12.3.1.7 References

IfcSurfaceTexture

8.12.3.1 IfcBlobTexture

8.12.3.1.1 Semantic definition