8.12.3.29 IfcSurfaceStyle

IfcSurfaceStyle is an assignment of one or many surface style elements to a surface, defined by subtypes of IfcSurface, IfcFaceBasedSurfaceModel, IfcShellBasedSurfaceModel, or by subtypes of IfcSolidModel. The positive direction of the surface normal relates to the positive side. In case of solids the outside of the solid is to be taken as positive side.

The surface style is often referred to as material definition in rendering applications. Corresponding ISO 10303 entity: surface_style_usage and surface_side_style. Please refer to ISO/IS 10303-46:1994 for the final definition of the formal standard. The surface style definition in regard to support of rendering has been greatly expanded beyond the scope of ISO/IS 10303-46. New entity in IFC2x.

8.12.3.29.2 Entity inheritance

- IfcPresentationStyle

8.12.3.29.3 Attributes

#	Attribute	Type	Description
IfcPresentationStyle (1)
1	Name	OPTIONAL IfcLabel	Name of the presentation style.
Click to show 1 hidden inherited attributes Click to hide 1 inherited attributes
IfcSurfaceStyle (2)
2	Side	IfcSurfaceSide	An indication of which side of the surface to apply the style.
3	Styles	SET [1:5] OF IfcSurfaceStyleElementSelect	A collection of different surface styles.

Table 8.12.3.29.E

8.12.3.29.4 Formal propositions

Name	Description
MaxOneExtDefined	The IfcExternallyDefinedSurfaceStyle shall only be used zero or one time within the set of Styles.
`SIZEOF(QUERY(Style <* SELF.Styles \| 'IFC4X3_DEV_bc7847cd.IFCEXTERNALLYDEFINEDSURFACESTYLE' IN TYPEOF(Style) )) <= 1`
MaxOneLighting	The IfcSurfaceStyleLighting shall only be used zero or one time within the set of Styles.
`SIZEOF(QUERY(Style <* SELF.Styles \| 'IFC4X3_DEV_bc7847cd.IFCSURFACESTYLELIGHTING' IN TYPEOF(Style) )) <= 1`
MaxOneRefraction	The IfcSurfaceStyleRefraction shall only be used zero or one time within the set of Styles.
`SIZEOF(QUERY(Style <* SELF.Styles \| 'IFC4X3_DEV_bc7847cd.IFCSURFACESTYLEREFRACTION' IN TYPEOF(Style) )) <= 1`
MaxOneShading	The IfcSurfaceStyleShading shall only be used zero or one time within the set of Styles.
`SIZEOF(QUERY(Style <* SELF.Styles \| 'IFC4X3_DEV_bc7847cd.IFCSURFACESTYLESHADING' IN TYPEOF(Style) )) <= 1`
MaxOneTextures	The IfcSurfaceStyleWithTextures shall only be used zero or one time within the set of Styles.
`SIZEOF(QUERY(Style <* SELF.Styles \| 'IFC4X3_DEV_bc7847cd.IFCSURFACESTYLEWITHTEXTURES' IN TYPEOF(Style) )) <= 1`

Table 8.12.3.29.F

8.12.3.29.5 Examples

Figure 8.12.3.29.A

Tessellation With Image Texture
Figure 8.12.3.29.B

Tessellation With Blob Texture
Figure 8.12.3.29.C

Tessellation With Pixel Texture
Figure 8.12.3.29.D

Linear Placement Of Signal

8.12.3.29.6 Formal representation

ENTITY IfcSurfaceStyle
 SUBTYPE OF (IfcPresentationStyle);
	Side : IfcSurfaceSide;
	Styles : SET [1:5] OF IfcSurfaceStyleElementSelect;
 WHERE
	MaxOneExtDefined : SIZEOF(QUERY(Style <* SELF.Styles |
  'IFC4X3_DEV_bc7847cd.IFCEXTERNALLYDEFINEDSURFACESTYLE' IN
   TYPEOF(Style)
  )) <= 1;
	MaxOneLighting : SIZEOF(QUERY(Style <* SELF.Styles |
  'IFC4X3_DEV_bc7847cd.IFCSURFACESTYLELIGHTING' IN
   TYPEOF(Style)
  )) <= 1;
	MaxOneRefraction : SIZEOF(QUERY(Style <* SELF.Styles |
  'IFC4X3_DEV_bc7847cd.IFCSURFACESTYLEREFRACTION' IN
   TYPEOF(Style)
  )) <= 1;
	MaxOneShading : SIZEOF(QUERY(Style <* SELF.Styles |
  'IFC4X3_DEV_bc7847cd.IFCSURFACESTYLESHADING' IN
   TYPEOF(Style)
  )) <= 1;
	MaxOneTextures : SIZEOF(QUERY(Style <* SELF.Styles |
  'IFC4X3_DEV_bc7847cd.IFCSURFACESTYLEWITHTEXTURES' IN
   TYPEOF(Style)
  )) <= 1;
END_ENTITY;

8.12.3.29.7 References

IfcPresentationStyle