handle vertical datums correctly

Author: civilx64

features/rules/GRF/GRF007_valid-vertical-datum-crs-type.feature

@@ -1,9 +1,11 @@
 @implementer-agreement
 @GRF
-@version1
+@version2
 Feature: GRF007 - Valid vertical datum CRS type
-The rule verifies that any coordinate reference system (CRS) assigned as a vertical datum is either a vertical CRS or a compound CRS containing a vertical component, to ensure valid height referencing.
+The rule verifies that any coordinate reference system (CRS) or datum assigned as a vertical datum is either a vertical CRS,
+a compound CRS containing a vertical component, or a vertical datum, to ensure valid height referencing.
 https://pyproj4.github.io/pyproj/stable/api/crs/crs.html
+https://pyproj4.github.io/pyproj/stable/api/crs/datum.html
 
 
   Scenario: WKT specification for missing EPSG in the name

features/steps/steps/crs.py

@@ -1,6 +1,8 @@
 from math import isclose
 from pyproj.database import query_crs_info
 from pyproj import CRS
+from pyproj.crs import Datum
+from pyproj.enums import WktVersion
 from validation_handling import gherkin_ifc
 import ifcopenshell.util.unit as unit
 
@@ -23,7 +25,18 @@ def step_impl(context, inst):
     if crs.is_compound or crs.is_vertical:
         yield ValidationOutcome(inst=inst, severity=OutcomeSeverity.PASSED)
     else:
-        yield ValidationOutcome(inst=inst, severity=OutcomeSeverity.ERROR)
+        # IfcProjectedCRS.VerticalDatum can also be just a vertical datum - doesn't need to be a full CRS definition
+        # example: https://epsg.io/5127-datum
+        if str(inst[:5]) == "EPSG:":
+            epsg_code = int(inst.split(":")[1])
+            vdatum = Datum.from_epsg(epsg_code)
+        else:
+            vdatum = Datum.from_string(inst)
+        wkt_repr = vdatum.to_wkt(version=WktVersion.WKT2_2019)
+        if wkt_repr.split("[")[0] == "VDATUM":
+            yield ValidationOutcome(inst=inst, severity=OutcomeSeverity.PASSED)
+        else:
+            yield ValidationOutcome(inst=inst, severity=OutcomeSeverity.ERROR)
 
 
 

test/files/GRF/grf007/fail-grf007-invalid_vertical_datum_espg_code.ifc

@@ -0,0 +1,33 @@
+ISO-10303-21;
+HEADER;
+FILE_DESCRIPTION(('ViewDefinition [ReferenceView]'),'2;1');
+FILE_NAME('fail-grf007-invalid_vertical_datum_espg_code.ifc','2023-01-25T18:40:40',(''),(''),'','redacted - redacted - v3.14159','');
+FILE_SCHEMA(('IFC4X3_ADD2'));
+ENDSEC;
+DATA;
+#1=IFCPERSON($,$,'',$,$,$,$,$);
+#2=IFCORGANIZATION($,'',$,$,$);
+#3=IFCPERSONANDORGANIZATION(#1,#2,$);
+#4=IFCAPPLICATION(#2,'redacted','redacted','');
+#5=IFCOWNERHISTORY(#3,#4,$,.NOCHANGE.,$,#3,#4,1674672040);
+#6=IFCDIRECTION((1.,0.,0.));
+#7=IFCDIRECTION((0.,0.,1.));
+#8=IFCCARTESIANPOINT((0.,0.,0.));
+#9=IFCAXIS2PLACEMENT3D(#8,#7,#6);
+#10=IFCDIRECTION((0.,1.));
+#11=IFCGEOMETRICREPRESENTATIONCONTEXT($,'Model',3,1.E-05,#9,#10);
+#12=IFCDIMENSIONALEXPONENTS(0,0,0,0,0,0,0);
+#13=IFCSIUNIT(*,.LENGTHUNIT.,$,.METRE.);
+#14=IFCSIUNIT(*,.AREAUNIT.,$,.SQUARE_METRE.);
+#15=IFCSIUNIT(*,.VOLUMEUNIT.,$,.CUBIC_METRE.);
+#16=IFCSIUNIT(*,.PLANEANGLEUNIT.,$,.RADIAN.);
+#17=IFCMEASUREWITHUNIT(IFCPLANEANGLEMEASURE(0.017453292519943295),#16);
+#18=IFCCONVERSIONBASEDUNIT(#12,.PLANEANGLEUNIT.,'DEGREE',#17);
+#19=IFCUNITASSIGNMENT((#13,#14,#15,#18));
+#20=IFCPROJECT('2X9wjf5oPB4PQjenCYrhHZ',#5,'',$,$,$,$,(#11),#19);
+#21=IFCPROJECTEDCRS('EPSG:2056','CH1903+ / LV95; heights in LN02 (EPSG:5728)','EPSG:6150','EPSG:6150','Swiss Oblique Mercator 1995',$,#13);
+#22=IFCMAPCONVERSION(#11,#21,316131.64,5690966.11,1.,1.,0.,$);
+#23=IFCGEOMETRICREPRESENTATIONCONTEXT($,'Model',3,1.E-05,#9,#10);
+#24=IFCMAPCONVERSION(#23,#21,316131.64,5690966.11,1.,1.,0.,$);
+ENDSEC;
+END-ISO-10303-21;