ui and decorator handler

src/ifcblenderexport/blenderbim/bim/.gitignore

@@ -0,0 +1,2 @@
+# addon writes tmp stuff directly to its dir
+/data/

src/ifcblenderexport/blenderbim/bim/decoration.py

@@ -0,0 +1,47 @@
+"""Viewport decorations"""
+from bpy.types import SpaceView3D
+import bpy
+import blf
+
+
+class ViewDecorator(object):
+    # class var for single handler
+    installed = None
+
+    @classmethod
+    def install(cls, *args, **kwargs):
+        handler = cls(*args, **kwargs)
+        cls.installed = SpaceView3D.draw_handler_add(handler, (), 'WINDOW', 'POST_PIXEL')
+
+    @classmethod
+    def uninstall(cls):
+        SpaceView3D.draw_handler_remove(cls.installed, 'WINDOW')
+        cls.installed = None
+
+
+class DimensionDecorator(ViewDecorator):
+    """Decorates dimension curves
+    - outlines each segment with an arrow
+    - puts metric text next to each segment
+    """
+
+    def __init__(self, scene, context):
+        self.scene = scene
+        self.context = context
+        self.font_id = 0
+        self.dpi = context.preferences.system.dpi
+        print("Created decorator", scene)
+
+    def __call__(self):
+        # get active drawing, if any
+        if self.scene.active_drawing_index is None or len(self.scene.drawings) == 0:
+            return
+        drawing = self.scene.drawings[self.scene.active_drawing_index]
+        collection = bpy.data.collections.get("IfcGroup/" + drawing.name)
+        if 'IfcAnnotation/Dimension' not in collection.all_objects:
+            return
+        curve = collection.all_objects['IfcAnnotation/Dimension'].data
+        text = repr(curve)
+        blf.position(self.font_id, 100, 100, 0)
+        blf.size(self.font_id, 10, self.dpi)
+        blf.draw(self.font_id, text)

src/ifcblenderexport/blenderbim/bim/prop.py

@@ -8,6 +8,7 @@ from . import schema
 from . import bcf
 from . import ifc
 from . import annotation
+from . import decoration
 import bpy
 from bpy.types import PropertyGroup
 from bpy.app.handlers import persistent
@@ -357,6 +358,14 @@ def refreshTitleblocks(self, context):
     getTitleblocks(self, context)
 
 
+def toggleDimDecorations(self, context):
+    toggle = self.dim_decorations
+    if toggle:
+        decoration.DimensionDecorator.install(self, context)
+    else:
+        decoration.DimensionDecorator.uninstall()
+
+
 def getScenarios(self, context):
     global scenarios_enum
     if len(scenarios_enum) < 1:
@@ -668,6 +677,7 @@ class DocProperties(PropertyGroup):
     active_sheet_index: IntProperty(name="Active Sheet Index")
     ifc_files: CollectionProperty(name="IFCs", type=StrProperty)
     drawing_styles: CollectionProperty(name="Drawing Styles", type=DrawingStyle)
+    dim_decorations: BoolProperty(name="Decorate dimentions", update=toggleDimDecorations)
 
 
 class BIMCameraProperties(PropertyGroup):

src/ifcblenderexport/blenderbim/bim/ui.py

@@ -2352,6 +2352,9 @@ class BIM_PT_annotation_utilities(Panel):
                 row.operator("bim.remove_drawing", icon="X", text="").index = props.active_drawing_index
             layout.template_list("BIM_UL_generic", "", props, "drawings", props, "active_drawing_index")
 
+        row = layout.row()
+        row.prop(props, 'dim_decorations')
+
 
 class BIM_PT_qto_utilities(Panel):
     bl_idname = "BIM_PT_qto_utilities"
@@ -2396,7 +2399,7 @@ class BIM_PT_clash_manager(Panel):
 
         row = layout.row()
         layout.label(text="Select output path for smart-grouped clashes:")
-        
+
         row = layout.row(align=True)
         row.prop(props, "smart_grouped_clashes_path", text="")
         op = row.operator("bim.select_smart_grouped_clashes_path", icon="FILE_FOLDER", text="")
@@ -2409,7 +2412,7 @@ class BIM_PT_clash_manager(Panel):
 
         row = layout.row(align=True)
         row.operator("bim.load_smart_groups_for_active_clash_set")
-        
+
         layout.template_list('BIM_UL_smart_groups', '', props, 'smart_clash_groups', props, 'active_smart_group_index')
 
         row = layout.row(align=True)