fix #7537 - Layer thickness correct when slab is rotated and few other features...

- Add dual-rotation support for AXIS3 slabs (IFC angle + object rotation)
- Fix profile editing to display horizontal projection for tilted slabs
- Fix AXIS2 layer slicing to use local extrusion direction for walls
- Fix ChangeExtrusionDepth to refresh geometry after depth changes
- Remove rotation lock on slabs to allow free rotation
- Fix undefined variable bug in add_slab_representation.py

src/ifcopenshell-python/ifcopenshell/api/geometry/add_slab_representation.py

@@ -100,35 +100,45 @@ class Usecase:
         size = self.convert_si_to_unit(1)
         points = ((0.0, 0.0), (size, 0.0), (size, size), (0.0, size), (0.0, 0.0))
         if self.polyline:
-            points = [
-                (self.convert_si_to_unit(p[0]), self.convert_si_to_unit(p[1] * abs(1 / cos(self.x_angle))))
-                for p in self.polyline
-            ]
+            # Only scale polyline if we have actual slope
+            if self.x_angle and abs(self.x_angle) > 1e-6:
+                points = [
+                    (self.convert_si_to_unit(p[0]), self.convert_si_to_unit(p[1] * abs(1 / cos(self.x_angle))))
+                    for p in self.polyline
+                ]
+            else:
+                points = [
+                    (self.convert_si_to_unit(p[0]), self.convert_si_to_unit(p[1]))
+                    for p in self.polyline
+                ]
+        
         if self.file.schema == "IFC2X3":
             curve = self.file.createIfcPolyline([self.file.createIfcCartesianPoint(p) for p in points])
         else:
             curve = self.file.createIfcIndexedPolyCurve(self.file.createIfcCartesianPointList2D(points))
-
+        
         if self.x_angle:
             direction_ratios = (0.0, sin(self.x_angle), cos(self.x_angle))
         else:
             direction_ratios = (0.0, 0.0, 1.0)
 
-        offset_direction = direction_ratios  # offset direction doesn't change if direction_sense is negative
         extrusion_direction = self.file.createIfcDirection(direction_ratios)
-        if self.direction_sense == "NEGATIVE":
-            direction_ratios = tuple(-n for n in direction_ratios)
-            extrusion_direction = self.file.createIfcDirection(direction_ratios)
-
-        perpendicular_offset = self.convert_si_to_unit(self.offset) * abs(1 / cos(self.x_angle))
-        perpendicular_depth = self.convert_si_to_unit(self.depth) * abs(1 / cos(self.x_angle))
+        
+        # Calculate depth based on extrusion angle
+        extrusion_angle = abs(self.x_angle) if self.x_angle else 0
+        if extrusion_angle > 1e-6:
+            perpendicular_depth = self.convert_si_to_unit(self.depth) * abs(1 / cos(extrusion_angle))
+            perpendicular_offset = self.convert_si_to_unit(self.offset) * abs(1 / cos(extrusion_angle))
+        else:
+            perpendicular_depth = self.convert_si_to_unit(self.depth)
+            perpendicular_offset = self.convert_si_to_unit(self.offset)
+            
         position = None
-        # default position for IFC2X3 where .Position is not optional
         if self.file.schema == "IFC2X3" or self.offset != 0:
             position_vector = (
-                offset_direction[0] * perpendicular_offset,
-                offset_direction[1] * perpendicular_offset,
-                offset_direction[2] * perpendicular_offset,
+                direction_ratios[0] * perpendicular_offset,
+                direction_ratios[1] * perpendicular_offset,
+                direction_ratios[2] * perpendicular_offset,
             )
             position = self.file.createIfcAxis2Placement3D(
                 self.file.createIfcCartesianPoint(position_vector),

src/ifcopenshell-python/ifcopenshell/api/geometry/add_wall_representation.py

@@ -85,7 +85,6 @@ class Usecase:
     def create_item(self) -> ifcopenshell.entity_instance:
         length = self.convert_si_to_unit(self.settings["length"])
         thickness = self.convert_si_to_unit(self.settings["thickness"])
-        thickness *= 1 / cos(self.settings["x_angle"])
         if self.settings["direction_sense"] == "NEGATIVE":
             thickness *= -1
         points = (
@@ -113,7 +112,7 @@ class Usecase:
                 self.file.createIfcDirection((1.0, 0.0, 0.0)),
             ),
             extrusion_direction,
-            self.convert_si_to_unit(self.settings["height"]) * abs(1 / cos(self.settings["x_angle"])),
+            self.convert_si_to_unit(self.settings["height"]),
         )
         if self.settings["booleans"]:
             extrusion = self.apply_booleans(extrusion)