New recipe to downgrade indexed poly curves, often used to allow IFC4 grids to show up in viewers like Revizto / XBim Xplorer / etc.

src/ifcpatch/ifcpatch/recipes/DowngradeIndexedPolyCurve.py

@@ -0,0 +1,31 @@
+import ifcopenshell
+import ifcopenshell.util.element
+
+
+class Patcher:
+    def __init__(self, src, file, logger, args=None):
+        self.src = src
+        self.file = file
+        self.logger = logger
+        self.args = args
+
+    def patch(self):
+        curve_map = {}
+
+        for curve in self.file.by_type("IfcIndexedPolyCurve"):
+            if "IfcArcIndex" in [s.is_a() for s in curve.Segments]:
+                print("Could not convert curve due to arcs", curve)
+                continue
+            coordinates = curve.Points.CoordList
+            points = []
+            for i, segment in enumerate(curve.Segments):
+                segment = segment.wrappedValue
+                if i == 0:
+                    points.append(self.file.createIfcCartesianPoint(coordinates[segment[0] - 1]))
+                points.append(self.file.createIfcCartesianPoint(coordinates[segment[1] - 1]))
+            polyline = self.file.create_entity("IfcPolyline", points)
+            curve_map[curve] = polyline
+
+        for curve, polyline in curve_map.items():
+            for inverse in self.file.get_inverse(curve):
+                ifcopenshell.util.element.replace_attribute(inverse, curve, polyline)