The IfcSurfaceStyleElementSelect provides a selection between different surface styles, including IfcSurfaceStyleRendering for rendering properties, IfcSurfaceStyleLighting, which holds the exact physically based lighting properties for lighting based calculation algorithms (as the opposite to the rendering based calculation), the IfcSurfaceStyleRefraction (for more advanced refraction indices) and IfcSurfaceStyleWithTextures to allow for image textures applied to surfaces. In addition an IfcExternallyDefinedSurfaceStyle can be selected that points into an external rendering material library.

NOTE  The IfcSurfaceLightingProperties are needed for exact lighting calculation, because physically based lighting calculation algorithms need exact physically based parameters. The factors in IfcSurfaceStyleRendering lack the physical base, they are intended for rendering calculations, but a lighting calculation based software cannot use these values.

NOTE  Definition according to ISO/CD 10303-46:1992
The surface style element select is a selection of the different surface styles to use in the presentation of the side of a surface.

NOTE  Type adapted from surface_style_element_select defined in ISO10303-46.

HISTORY  New select type in IFC2x2.