Add support for breakline annotations

src/ifcblenderexport/blenderbim/bim/cut_ifc.py

@@ -861,6 +861,9 @@ class SvgWriter():
         if self.ifc_cutter.dimension_obj:
             self.draw_dimension_annotations(self.ifc_cutter.dimension_obj)
 
+        if self.ifc_cutter.break_obj:
+            self.draw_break_annotations(self.ifc_cutter.break_obj)
+
         for grid_obj in self.ifc_cutter.grid_objs:
             matrix_world = grid_obj.matrix_world
             for edge in grid_obj.data.edges:
@@ -1056,6 +1059,30 @@ class SvgWriter():
                     }
                 ))
 
+    def draw_break_annotations(self, break_obj):
+        x_offset = self.raw_width / 2
+        y_offset = self.raw_height / 2
+
+        matrix_world = break_obj.matrix_world
+        for polygon in break_obj.data.polygons:
+            points = [break_obj.data.vertices[v] for v in polygon.vertices]
+            projected_points = [self.project_point_onto_camera(matrix_world @ p.co.xyz) for p in points]
+            d = ' '.join(['L {} {}'.format(
+                (x_offset + p.x) * self.scale, (y_offset - p.y) * self.scale)
+                for p in projected_points])
+            d = 'M{}'.format(d[1:])
+            path = self.svg.add(self.svg.path(d=d, class_=' '.join(['break'])))
+
+            break_points = [
+                projected_points[0],
+                ((projected_points[1]-projected_points[0])/2)+projected_points[0],
+                projected_points[1]]
+            d = ' '.join(['L {} {}'.format(
+                (x_offset + p.x) * self.scale, (y_offset - p.y) * self.scale)
+                for p in break_points])
+            d = 'M{}'.format(d[1:])
+            path = self.svg.add(self.svg.path(d=d, class_=' '.join(['breakline'])))
+
     def draw_dimension_annotations(self, dimension_obj, text_override=None):
         x_offset = self.raw_width / 2
         y_offset = self.raw_height / 2

src/ifcblenderexport/blenderbim/bim/data/styles/default.css

@@ -4,6 +4,8 @@
 .hidden { stroke-dasharray: 3, 2; }
 .leader { marker-end: url(#leader-marker); }
 .stair { marker-start: url(#stair-marker-start); marker-end: url(#stair-marker-end); }
+.break { fill: white; }
+.breakline { fill: none; stroke: black; stroke-linecap: 'round'; stroke-width: 0.25; marker-mid: url(#breakline-marker); }
 .solid {}
 .material-diagonal1 { fill: url(#diagonal1); }
 .material-diagonal2 { fill: url(#diagonal2); }

src/ifcblenderexport/blenderbim/bim/data/templates/markers.svg

@@ -53,4 +53,10 @@
             <path d="M 0 1 L 90 1" class="annotation" style="stroke-width:1;" />
         </g>
     </marker>
+    <marker id="breakline-marker" markerHeight="20" markerWidth="15" refX="7.5" refY="10">
+        <g>
+            <path d="M 0 10 L 5 20 L 7.5 10" class="annotation" style="stroke-width:1; fill: white;" />
+            <path d="M 7.5 10 L 10 0 L 15 10" class="annotation" style="stroke-width:1; fill: white;" />
+        </g>
+    </marker>
 </svg>

src/ifcblenderexport/blenderbim/bim/operator.py

@@ -1579,6 +1579,7 @@ class CutSection(bpy.types.Operator):
         ifc_cutter.leader_obj = None
         ifc_cutter.stair_obj = None
         ifc_cutter.dimension_obj = None
+        ifc_cutter.break_obj = None
         ifc_cutter.equal_obj = None
         ifc_cutter.hidden_objs = []
         ifc_cutter.solid_objs = []
@@ -1595,6 +1596,8 @@ class CutSection(bpy.types.Operator):
                 ifc_cutter.equal_obj = obj
             elif 'Dimension' in obj.name:
                 ifc_cutter.dimension_obj = obj
+            elif 'Break' in obj.name:
+                ifc_cutter.break_obj = obj
             elif 'Hidden' in obj.name:
                 ifc_cutter.hidden_objs.append((obj, obj.data))
             elif 'Solid' in obj.name: