IFC 4.3.0.1 (IFC4X3) development

# 8.12.3.14 IfcFillAreaStyle

## 8.12.3.14.1 Semantic definition

An IfcFillAreaStyle provides the style table for presentation information assigned to annotation fill areas or surfaces for hatching and tiling. The IfcFillAreaStyle_defines hatches as model hatches, that is, the distance between hatch lines, or the curve patterns of hatch lines are given in model space dimensions (that have to be scaled using the target plot scale). The _IfcFillAreaStyle allows for the following combinations of defining the style of hatching and tiling:

• Solid fill for areas and surfaces by only assigning IfcColour to the set of FillStyles. It then provides the background colour for the filled area or surface.
• Vector based hatching for areas and surfaces based on a single row of hatch lines by assigning a single instance of IfcFillAreaStyleHatching to the set of FillStyles.

• If an instance of IfcColour is assigned in addition to the set of FillStyles, it provides the background colour for the hatching.
• Vector based hatching for areas and surfaces based on two (potentially crossing) rows of hatch lines by assigning two instances of IfcFillAreaStyleHatching to the set of FillStyles.

• If an instance of IfcColour is assigned in addition to the set of FillStyles, it provides the background colour for the hatching.
• Externally defined hatch style by assigning a single instance of IfcExternallyDefinedHatchStyle to the set of FillStyles.
• If an instance of IfcColour is assigned in addition to the set of FillStyles, it provides the background colour for the hatching.

Measures given to a hatch or tile pattern are given in global drawing length units.

The measure values for hatch or tile pattern apply to the model space with a target plot scale provided for the correct appearance in the default plot scale. For different scale and projection dependent fill area styles a different instance of IfcFillAreaStyle needs to be used by IfcPresentationStyleAssignment for different IfcGeometricRepresentationSubContext dependent representations.

An IfcFillAreaStyle can be assigned to IfcFillArea via the IfcPresentationStyleAssignment through an intermediate IfcStyledItem or subtype IfcAnnotationFillAreaOccurrence.

## 8.12.3.14.5 Formal representation

ENTITY IfcFillAreaStyle
SUBTYPE OF (IfcPresentationStyle);
FillStyles : SET [1:?] OF IfcFillStyleSelect;
ModelOrDraughting : OPTIONAL IfcBoolean;
WHERE
ConsistentHatchStyleDef : IfcCorrectFillAreaStyle(SELF.FillStyles);
MaxOneColour : SIZEOF(QUERY(Style <* SELF.FillStyles |
'IFC4X3_DEV_70ce626d.IFCCOLOUR' IN
TYPEOF(Style)
)) <= 1;
MaxOneExtHatchStyle : SIZEOF(QUERY(Style <* SELF.FillStyles |
'IFC4X3_DEV_70ce626d.IFCEXTERNALLYDEFINEDHATCHSTYLE' IN
TYPEOF(Style)
)) <= 1;
END_ENTITY;