8.9.6.26 IfcVectorDifference
8.9.6.26.1 Semantic definition
{ .extDef}
8.9.6.26.2 Formal representation
FUNCTION IfcVectorDifference
(Arg1, Arg2 : IfcVectorOrDirection)
: IfcVector;
LOCAL
Result : IfcVector;
Res, Vec1, Vec2 : IfcDirection;
Mag, Mag1, Mag2 : REAL;
Ndim : INTEGER;
END_LOCAL;
IF ((NOT EXISTS (Arg1)) OR (NOT EXISTS (Arg2))) OR (Arg1.Dim <> Arg2.Dim) THEN
RETURN (?) ;
ELSE
BEGIN
IF 'IFC4X4_DEV_20260525.IFCVECTOR' IN TYPEOF(Arg1) THEN
Mag1 := Arg1\IfcVector.Magnitude;
Vec1 := Arg1\IfcVector.Orientation;
ELSE
Mag1 := 1.0;
Vec1 := Arg1;
END_IF;
IF 'IFC4X4_DEV_20260525.IFCVECTOR' IN TYPEOF(Arg2) THEN
Mag2 := Arg2\IfcVector.Magnitude;
Vec2 := Arg2\IfcVector.Orientation;
ELSE
Mag2 := 1.0;
Vec2 := Arg2;
END_IF;
Vec1 := IfcNormalise (Vec1);
Vec2 := IfcNormalise (Vec2);
Ndim := SIZEOF(Vec1.DirectionRatios);
Mag := 0.0;
Res := IfcRepresentationItem() || IfcGeometricRepresentationItem () || IfcDirection([0.0:Ndim]);
REPEAT i := 1 TO Ndim;
Res.DirectionRatios[i] := Mag1*Vec1.DirectionRatios[i] - Mag2*Vec2.DirectionRatios[i];
Mag := Mag + (Res.DirectionRatios[i]*Res.DirectionRatios[i]);
END_REPEAT;
IF (Mag > 0.0 ) THEN
Result := IfcRepresentationItem() || IfcGeometricRepresentationItem () || IfcVector( Res, SQRT(Mag));
ELSE
Result := IfcRepresentationItem() || IfcGeometricRepresentationItem () || IfcVector( Vec1, 0.0);
END_IF;
END;
END_IF;
RETURN (Result);
END_FUNCTION;
