WIP support for cutting a section with dimension annotation lines

src/ifcblenderexport/blenderbim/__init__.py

@@ -61,8 +61,10 @@ classes = (
     operator.FetchObjectPassport,
     operator.AddSubcontext,
     operator.RemoveSubcontext,
+    operator.CutSection,
     prop.Subcontext,
     prop.BIMProperties,
+    prop.DocProperties,
     prop.BIMLibrary,
     prop.MapConversion,
     prop.TargetCRS,
@@ -75,6 +77,7 @@ classes = (
     prop.BIMMaterialProperties,
     prop.SweptSolid,
     prop.BIMMeshProperties,
+    ui.BIM_PT_documentation,
     ui.BIM_PT_bim,
     ui.BIM_PT_context,
     ui.BIM_PT_qa,
@@ -102,6 +105,7 @@ def register():
     bpy.types.TOPBAR_MT_file_export.append(menu_func_export)
     bpy.types.TOPBAR_MT_file_import.append(menu_func_import)
     bpy.types.Scene.BIMProperties = bpy.props.PointerProperty(type=prop.BIMProperties)
+    bpy.types.Scene.DocProperties = bpy.props.PointerProperty(type=prop.DocProperties)
     bpy.types.Scene.BIMLibrary = bpy.props.PointerProperty(type=prop.BIMLibrary)
     bpy.types.Scene.MapConversion = bpy.props.PointerProperty(type=prop.MapConversion)
     bpy.types.Scene.TargetCRS = bpy.props.PointerProperty(type=prop.TargetCRS)
@@ -117,6 +121,7 @@ def unregister():
     bpy.types.TOPBAR_MT_file_export.remove(menu_func_export)
     bpy.types.TOPBAR_MT_file_import.remove(menu_func_import)
     del(bpy.types.Scene.BIMProperties)
+    del(bpy.types.Scene.DocProperties)
     del(bpy.types.Scene.MapConversion)
     del(bpy.types.Scene.TargetCRS)
     del(bpy.types.Object.BIMObjectProperties)

src/ifcblenderexport/blenderbim/cut_ifc.py

@@ -1,11 +1,19 @@
 import os
 import math
-import svgwrite
 import time
 import numpy
 import pickle
+import sys
 from pathlib import Path
+from mathutils import Vector
+import xml.etree.ElementTree as ET
 
+# This hack is required to get the svgwrite dependency to load
+# TODO: decouple cutter into its own binary
+cwd = os.path.dirname(os.path.realpath(__file__)) + os.path.sep
+sys.path.append(cwd)
+
+import svgwrite
 import OCC.gp
 import OCC.Geom
 import OCC.Bnd
@@ -43,11 +51,14 @@ class IfcCutter:
         self.product_shapes = []
         self.background_elements = []
         self.cut_polygons = []
+        self.data_dir = ''
         self.ifc_files = []
         self.unit = None
         self.resolved_pixels = set()
         self.should_get_background = False
         self.pickle_file = 'shapes.pickle'
+        self.diagram_name = None
+        self.background_image = None
         self.section_box = {
             'projection': (0, 1, 0),
             'x_axis': (1, 0, 0),
@@ -103,7 +114,7 @@ class IfcCutter:
         print('# Timer logged at {:.2f} seconds'.format(time.time() - start_time))
 
     def load_ifc_files(self):
-        for filename in Path('ifc/').glob('*.ifc'):
+        for filename in Path(self.data_dir).glob('*.ifc'):
             print('Loading file {} ...'.format(filename))
             self.ifc_files.append(ifcopenshell.open(filename))
 
@@ -558,6 +569,24 @@ class IfcCutterDebug(IfcCutter):
                 ifcopenshell.geom.utils.display_shape(element['geometry_face'])
         input('Debug: showing background elements.')
 
+
+class External(svgwrite.container.Group):
+    def __init__(self, xml, **extra):
+        self.xml = xml
+
+        # Remove namespace
+        ns = u'{http://www.w3.org/2000/svg}'
+        nsl = len(ns)
+        for elem in self.xml.getiterator():
+            if elem.tag.startswith(ns):
+                elem.tag = elem.tag[nsl:]
+
+        super(External, self).__init__(**extra)
+
+    def get_xml(self):
+        return self.xml
+
+
 class SvgWriter():
     def __init__(self, ifc_cutter):
         self.ifc_cutter = ifc_cutter
@@ -565,27 +594,52 @@ class SvgWriter():
 
     def write(self):
         self.calculate_scale()
-        self.svg = svgwrite.Drawing('output.svg',
+        self.output = os.path.join(
+            self.ifc_cutter.data_dir,
+            'diagrams',
+            self.ifc_cutter.diagram_name + '.svg'
+        )
+        self.svg = svgwrite.Drawing(
+            self.output,
             debug=False,
-            size=('{}mm'.format(self.ifc_cutter.section_box['x'] * self.scale),
-                '{}mm'.format(self.ifc_cutter.section_box['y'] * self.scale)),
-            viewBox=('0 0 {} {}'.format(
-                self.ifc_cutter.section_box['x'] * self.scale,
-                self.ifc_cutter.section_box['y'] * self.scale)))
+            size=('{}mm'.format(self.width), '{}mm'.format(self.height)),
+            viewBox=('0 0 {} {}'.format(self.width, self.height)))
+
         self.add_stylesheet()
+        self.add_defs()
+        self.draw_background_image()
         self.draw_background_elements()
         self.draw_cut_polygons()
+        self.draw_annotations()
         self.svg.save(pretty=True)
 
     def calculate_scale(self):
         # TODO: properly handle units
         if self.ifc_cutter.unit.Name == 'METRE':
             self.scale *= 1000
+        self.raw_width = self.ifc_cutter.section_box['x']
+        self.raw_height = self.ifc_cutter.section_box['y']
+        self.width = self.raw_width * self.scale
+        self.height = self.raw_height * self.scale
 
     def add_stylesheet(self):
-        with open('styles/default.css', 'r') as stylesheet:
+        with open('{}styles/default.css'.format(self.ifc_cutter.data_dir), 'r') as stylesheet:
             self.svg.defs.add(self.svg.style(stylesheet.read()))
 
+    def add_defs(self):
+        tree = ET.parse('{}styles/defs.svg'.format(self.ifc_cutter.data_dir))
+        root = tree.getroot()
+        for child in root.getchildren():
+            self.svg.defs.add(External(child))
+
+    def draw_background_image(self):
+        self.svg.add(self.svg.image(
+            os.path.basename(self.ifc_cutter.background_image), **{
+                'width': self.width,
+                'height': self.height
+            }
+        ))
+
     def draw_background_elements(self):
         for element in self.ifc_cutter.background_elements:
             if element['type'] == 'polygon':
@@ -595,6 +649,19 @@ class SvgWriter():
             elif element['type'] == 'line':
                 self.draw_line(element, 'background')
 
+    def draw_annotations(self):
+        x_offset = self.raw_width / 2
+        y_offset = self.raw_height / 2
+        for edge in self.ifc_cutter.annotation_obj.data.edges:
+            classes = ['annotation', 'dimension']
+            v0 = self.ifc_cutter.annotation_obj.data.vertices[edge.vertices[0]].co
+            v1 = self.ifc_cutter.annotation_obj.data.vertices[edge.vertices[1]].co
+            start = ((x_offset + v0.x) * self.scale, (y_offset - v0.y) * self.scale)
+            end = ((x_offset + v1.x) * self.scale, (y_offset - v1.y) * self.scale)
+            line = self.svg.add(self.svg.line(start=start, end=end, class_=' '.join(classes)))
+            line['marker-start'] = 'url(#dimension-marker)'
+            line['marker-end'] = 'url(#dimension-marker)'
+
     def draw_cut_polygons(self):
         for polygon in self.ifc_cutter.cut_polygons:
             self.draw_polygon(polygon, 'cut')
@@ -636,12 +703,3 @@ class SvgWriter():
                 classes.append('material-{}'.format(association.RelatingMaterial.Name))
         classes.append('globalid-{}'.format(element.GlobalId))
         return classes
-
-print('# Starting process')
-ifc_cutter = IfcCutter()
-#ifc_cutter = IfcCutterDebug()
-svg_writer = SvgWriter(ifc_cutter)
-ifc_cutter.cut()
-start_time = time.time()
-svg_writer.write()
-print('# SVG writing finished in {:.2f} seconds'.format(time.time() - start_time))

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

@@ -0,0 +1,3 @@
+.cut { fill: black; stroke: black; stroke-linecap: 'round'; stroke-width: 0.3px; }
+.background { fill: white; stroke: black; stroke-linecap: 'round'; stroke-width: 0.05px; }
+.annotation { stroke: black; stroke-linecap: 'round'; stroke-width: 0.05px; }

src/ifcblenderexport/blenderbim/data/styles/defs.svg

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<svg baseProfile="full" version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:ev="http://www.w3.org/2001/xml-events" xmlns:xlink="http://www.w3.org/1999/xlink">
+    <marker id="dimension-marker" markerHeight="20" markerWidth="20" refX="7.5" refY="10" orient="auto">
+        <path d="M 7.5 0 L 7.5 20" class="annotation" style="stroke-width:2px;" />
+        <path d="M 0 0 L 15 20" class="annotation" style="stroke-width:3px;" />
+    </marker>
+</svg>

src/ifcblenderexport/blenderbim/operator.py

@@ -6,8 +6,10 @@ import logging
 from . import ifcopenshell
 from . import export_ifc
 from . import import_ifc
+from . import cut_ifc
 from bpy_extras.io_utils import ImportHelper
 from itertools import cycle
+from mathutils import Vector
 
 class ExportIFC(bpy.types.Operator):
     bl_idname = "export.ifc"
@@ -751,3 +753,59 @@ class RemoveSubcontext(bpy.types.Operator):
         subcontext_index = int(subcontext_index)
         getattr(bpy.context.scene.BIMProperties, '{}_subcontexts'.format(context)).remove(subcontext_index)
         return {'FINISHED'}
+
+
+class CutSection(bpy.types.Operator):
+    bl_idname = 'bim.cut_section'
+    bl_label = 'Cut Section'
+
+    def execute(self, context):
+        camera = bpy.context.active_object
+        if not (camera.type == 'CAMERA' and camera.data.type == 'ORTHO'):
+            return {'FINISHED'}
+        self.diagram_name = camera.name
+        bpy.context.scene.render.filepath = os.path.join(
+            bpy.context.scene.BIMProperties.data_dir,
+            'diagrams',
+            '{}.png'.format(self.diagram_name)
+        )
+        bpy.ops.render.render(write_still=True)
+        location = camera.location
+        render = bpy.context.scene.render
+        if self.is_landscape():
+            width = camera.data.ortho_scale
+            height = width / render.resolution_x * render.resolution_y
+        else:
+            height = camera.data.ortho_scale
+            width = height / render.resolution_y * render.resolution_x
+        depth = camera.data.clip_end
+        projection = camera.matrix_world.to_quaternion() @ Vector((0, 0, -1))
+        x_axis = camera.matrix_world.to_quaternion() @ Vector((1, 0, 0))
+        y_axis = camera.matrix_world.to_quaternion() @ Vector((0, -1, 0))
+        top_left_corner = location - (width / 2 * x_axis) - (height / 2 * y_axis)
+        ifc_cutter = cut_ifc.IfcCutter()
+        ifc_cutter.data_dir = bpy.context.scene.BIMProperties.data_dir
+        ifc_cutter.diagram_name = self.diagram_name
+        ifc_cutter.background_image = bpy.context.scene.render.filepath
+        ifc_cutter.annotation_obj = bpy.data.objects['{}-Annotation'.format(
+            self.diagram_name
+        )]
+        ifc_cutter.section_box = {
+            'projection': tuple(projection),
+            'x_axis': tuple(x_axis),
+            'y_axis': tuple(y_axis),
+            'top_left_corner': tuple(top_left_corner),
+            'x': width,
+            'y': height,
+            'z': depth,
+            'shape': None,
+            'face': None
+        }
+        ifc_cutter.pickle_file = os.path.join(ifc_cutter.data_dir, 'shapes.pickle')
+        svg_writer = cut_ifc.SvgWriter(ifc_cutter)
+        ifc_cutter.cut()
+        svg_writer.write()
+        return {'FINISHED'}
+
+    def is_landscape(self):
+        return bpy.context.scene.render.resolution_x > bpy.context.scene.render.resolution_y

src/ifcblenderexport/blenderbim/prop.py

@@ -171,6 +171,10 @@ class Subcontext(PropertyGroup):
     target_view: StringProperty(name='Target View')
 
 
+class DocProperties(PropertyGroup):
+    blah: StringProperty(name="Blah")
+
+
 class BIMProperties(PropertyGroup):
     schema_dir: StringProperty(default=os.path.join(cwd ,'schema') + os.path.sep, name="Schema Directory")
     data_dir: StringProperty(default=os.path.join(cwd, 'data') + os.path.sep, name="Data Directory")

src/ifcblenderexport/blenderbim/ui.py

@@ -182,6 +182,20 @@ class BIM_PT_gis(Panel):
         layout.row().prop(scene.TargetCRS, 'map_unit')
 
 
+class BIM_PT_documentation(Panel):
+    bl_label = "Diagrammatic Documentation"
+    bl_idname = "BIM_PT_documentation"
+    bl_space_type = 'PROPERTIES'
+    bl_region_type = 'WINDOW'
+    bl_context = 'output'
+
+    def draw(self, context):
+        layout = self.layout
+        props = bpy.context.scene.DocProperties
+
+        row = layout.row()
+        row.operator('bim.cut_section')
+
 class BIM_PT_context(Panel):
     bl_label = "Geometric Representation Contexts"
     bl_idname = "BIM_PT_context"