Skip to content

IfcSurfaceOfLinearExtrusion #202

Open
@SteveLockley

Description

@SteveLockley

Have been working on our IFC parser and notice and error in some recent exports from Revit 2020

If I understand the schema correctly the Depth parameter should be in model units, but it appears to be in Feet (8.23490813648297 should be 2,510mm). The Local origin of the Position is a repeat of the start origin of the swept curve. This causes the surface location to be translated twice as much as required. See point #26 below
Finally, the Swept curve is an IfcProfileDef which should be 2D. The exporter is writing out 3D profile defs. Rational BSpline #39 is 3D but on a plane so could be 2D).
Here is a sample of the IFC showing the problem, #26 is highlighted which I think shows the incorrect values

#13=IFCCARTESIANPOINT((-76.2000000000109,13189.05,27.));
#14=IFCCARTESIANPOINT((-76.2000000000109,13150.95,27.));
#15=IFCORIENTEDEDGE(,,#16,.T.);
#16=IFCEDGECURVE(#10,#17,#19,.T.);
#17=IFCVERTEXPOINT(#18);
#18=IFCCARTESIANPOINT((0.,13150.95,2537.));
#19=IFCTRIMMEDCURVE(#20,(#11),(#18),.T.,.CARTESIAN.);
#20=IFCLINE(#11,#21);
#21=IFCVECTOR(#22,304.8);
#22=IFCDIRECTION((0.,0.,1.));
#23=IFCORIENTEDEDGE(,,#24,.T.);
#24=IFCEDGECURVE(#17,#25,#27,.T.);
#25=IFCVERTEXPOINT(#26);
#26=IFCCARTESIANPOINT((0.,13189.05,2537.));
#27=IFCRATIONALBSPLINECURVEWITHKNOTS(3,(#18,#28,#29,#26),.UNSPECIFIED.,.F.,.U.,(4,4),(0.,1.),.UNSPECIFIED.,(1.,0.333333333333333,0.333333333333333,1.));
#28=IFCCARTESIANPOINT((-76.2000000000109,13150.95,2537.));
#29=IFCCARTESIANPOINT((-76.2000000000109,13189.05,2537.));
#30=IFCORIENTEDEDGE(,,#31,.T.);
#31=IFCEDGECURVE(#25,#8,#32,.T.);
#32=IFCTRIMMEDCURVE(#33,(#26),(#9),.T.,.CARTESIAN.);
#33=IFCLINE(#26,#34);
#34=IFCVECTOR(#35,304.8);
#35=IFCDIRECTION((0.,0.,-1.));
#36=IFCSURFACEOFLINEAREXTRUSION(#37,#40,#35,8.23490813648297);
#37=IFCARBITRARYOPENPROFILEDEF(.CURVE.,'Ruled Face Profile Curve',#38);
#38=IFCTRIMMEDCURVE(#39,(#26),(#18),.T.,.CARTESIAN.);
#39=IFCRATIONALBSPLINECURVEWITHKNOTS(3,(#26,#29,#28,#18),.UNSPECIFIED.,.F.,.U.,(4,4),(0.,1.),.UNSPECIFIED.,(1.,0.333333333333333,0.333333333333333,1.));
#40=IFCAXIS2PLACEMENT3D(#26,#35,#41);
#41=IFCDIRECTION((-1.,0.,0.));

Metadata

Metadata

Assignees

No one assigned

    Labels

    2020versionIFC mappingIssues with mapping Revit entities to IFC classesRevitcoordinate systemErrors in non-aligned model origin coordinatesexportIssue with exporting process or resultsproblemSomething isn't working

    Type

    No type

    Projects

    No projects

    Milestone

    No milestone

    Relationships

    None yet

    Development

    No branches or pull requests

    Issue actions