From 60fa05a9134c4faca4135bb2231adf211a84a57b Mon Sep 17 00:00:00 2001
From: Dion Moult <dion@thinkmoult.com>
Date: Sun, 12 Feb 2023 18:58:49 +1100
Subject: [PATCH] Fix #2521. Fill areas have limited dissolve applied before
 rendering.

---
 .../blenderbim/bim/data/styles/default.css          | 12 ++++++------
 .../blenderbim/bim/module/drawing/svgwriter.py      | 13 ++++++++++---
 2 files changed, 16 insertions(+), 9 deletions(-)

diff --git a/src/blenderbim/blenderbim/bim/data/styles/default.css b/src/blenderbim/blenderbim/bim/data/styles/default.css
index 36f81edcd3..09adb822bc 100644
--- a/src/blenderbim/blenderbim/bim/data/styles/default.css
+++ b/src/blenderbim/blenderbim/bim/data/styles/default.css
@@ -39,16 +39,16 @@ text { /* 2.5mm */ fill: black; stroke: none; font-family: 'OpenGost Type B TT';
 .PredefinedType-BOUNDARY { fill: none; stroke: red; stroke-width: 1; stroke-dasharray: 12, 4, 3, 4, 3, 4; }
 .PredefinedType-BATTING { marker-start: url(#batting); stroke: none; }
 .PredefinedType-SEALANT { fill: url(#crosshatch1); stroke-width: 0.25; }
-.PredefinedType-FILLAREA { fill: white; stroke: none; }
+.PredefinedType-FILLAREA { fill: white; stroke: black; }
 .PredefinedType-BREAKLINE { fill: none; stroke: black; stroke-width: 0.25; marker-mid: url(#breakline-marker); }
 .PredefinedType-TEXT { fill: black; stroke: none; }
 path.PredefinedType-TEXTLEADER { marker-end: url(#leader-marker); }
 text.PredefinedType-TEXTLEADER { fill: black; stroke: none; }
-text.title { /* 7mm */ fill: black; stroke: none; font-family: 'OpenGost Type B TT'; font-size: 11.55px; }
-text.header { /* 5mm */ fill: black; stroke: none; font-family: 'OpenGost Type B TT'; font-size: 8.25px; }
-text.large { /* 3.5mm */ fill: black; stroke: none; font-family: 'OpenGost Type B TT'; font-size: 5.78px; }
-text.regular { /* 2.5mm */ fill: black; stroke: none; font-family: 'OpenGost Type B TT'; font-size: 4.13px; }
-text.small { /* 1.8mm */ fill: black; stroke: none; font-family: 'OpenGost Type B TT'; font-size: 2.97px; }
+text.title { /* 7mm */ font-size: 11.55px; }
+text.header { /* 5mm */ font-size: 8.25px; }
+text.large { /* 3.5mm */ font-size: 5.78px; }
+text.regular { /* 2.5mm */ font-size: 4.13px; }
+text.small { /* 1.8mm */ font-size: 2.97px; }
 .material-blank { fill: white; }
 .material-diagonal1 { fill: url(#diagonal1); }
 .material-diagonal2 { fill: url(#diagonal2); }
diff --git a/src/blenderbim/blenderbim/bim/module/drawing/svgwriter.py b/src/blenderbim/blenderbim/bim/module/drawing/svgwriter.py
index 3a1810d5c1..ae1d1d64ae 100644
--- a/src/blenderbim/blenderbim/bim/module/drawing/svgwriter.py
+++ b/src/blenderbim/blenderbim/bim/module/drawing/svgwriter.py
@@ -31,6 +31,7 @@ import ifcopenshell.util.representation
 import blenderbim.tool as tool
 import blenderbim.bim.module.drawing.helper as helper
 import blenderbim.bim.module.drawing.annotation as annotation
+from math import pi
 from mathutils import Vector
 from mathutils import geometry
 from blenderbim.bim.ifc import IfcStore
@@ -290,16 +291,22 @@ class SvgWriter:
         # from Blender. In the future, it should probably come from IFC.
         if not isinstance(obj.data, bpy.types.Mesh):
             return
+
         classes = self.get_attribute_classes(obj)
         if len(obj.data.polygons) == 0:
             self.draw_edge_annotation(obj, classes)
             return
+
+        bm = bmesh.new()
+        bm.from_mesh(obj.data)
+        bmesh.ops.dissolve_limit(bm, angle_limit=pi / 180 * 1, verts=bm.verts, edges=bm.edges)
+        bm.faces.ensure_lookup_table()
+
         x_offset = self.raw_width / 2
         y_offset = self.raw_height / 2
         matrix_world = obj.matrix_world
-        for polygon in obj.data.polygons:
-            points = [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]
+        for face in bm.faces:
+            projected_points = [self.project_point_onto_camera(matrix_world @ p.co.xyz) for p in face.verts]
             projected_points.append(projected_points[0])
             d = " ".join(
                 [