IFC Stair - added "Wood / Steel" stair type

Added new stair type "Wood / Steel" to IFC Stair modifier. It's less sophisticated than "Concrete" stair type - it acts more like a "Dumb stair" operator we have.

src/blenderbim/blenderbim/bim/module/model/prop.py

@@ -273,7 +273,8 @@ class BIMStairProperties(PropertyGroup):
     stair_type: bpy.props.EnumProperty(name="Stair type", items=stair_types, default="CONCRETE")
 
     def get_props_kwargs(self):
-        kwargs = {
+        if self.stair_type == "CONCRETE":
+            return {
                 "stair_type": self.stair_type,
                 "width": self.width,
                 "height": self.height,
@@ -284,4 +285,12 @@ class BIMStairProperties(PropertyGroup):
                 "top_slab_depth": self.top_slab_depth,
                 "has_top_nib": self.has_top_nib,
             }
-        return kwargs
+        elif self.stair_type == "WOOD/STEEL":
+            return {
+                "stair_type": self.stair_type,
+                "width": self.width,
+                "height": self.height,
+                "number_of_treads": self.number_of_treads,
+                "tread_depth": self.tread_depth,
+                "tread_run": self.tread_run,
+            }

src/blenderbim/blenderbim/bim/module/model/stair.py

@@ -89,18 +89,39 @@ def generate_stair_2d_profile(
     width,
     tread_run,
     tread_depth,
-    has_top_nib,
-    top_slab_depth,
-    base_slab_depth,
     stair_type,
+    # CONCRETE STAIR ARGUMENTS
+    has_top_nib=None,
+    top_slab_depth=None,
+    base_slab_depth=None,
 ):
     vertices = []
     edges = []
+    faces = []
 
     number_of_risers = number_of_treads + 1
     tread_rise = height / number_of_risers
     length = tread_run * number_of_risers
 
+    if stair_type == "WOOD/STEEL":
+        for i in range(number_of_risers):
+            v1 = Vector(((i + 1) * tread_run, 0, (i + 1) * tread_rise))
+            v0 = v1 - Vector((tread_run, 0, 0))
+            v2 = v1 - Vector((0, 0, tread_depth))
+            v3 = v0 - Vector((0, 0, tread_depth))
+            vertices.extend([v0, v1, v2, v3])
+
+            cur_vertex = i * 4
+            edges.extend([
+                (cur_vertex, cur_vertex+1),
+                (cur_vertex+1, cur_vertex+2),
+                (cur_vertex+2, cur_vertex+3),
+                (cur_vertex+3, cur_vertex),
+            ])
+            faces.append(list(range(4 * i, 4 * i + 1)))
+
+        return (vertices, edges, faces)
+    elif stair_type == "CONCRETE":
         for i in range(number_of_risers):
             vertices.extend([
                 Vector((tread_run*i, 0, tread_rise*i)),
@@ -177,7 +198,7 @@ def update_stair_modifier(context):
     bmesh.ops.contextual_create(bm, geom=new_edges)
 
     bm.faces.ensure_lookup_table()
-    faces = [bm.faces[0]]
+    faces = bm.faces
     extruded = bmesh.ops.extrude_face_region(bm, geom=faces)
     extrusion_vector = Vector((0, 1, 0)) * props.width
     translate_verts = [v for v in extruded["geom"] if isinstance(v, BMVert)]