add min_width option

src/c3nav/mapdata/management/commands/rendermap.py

@@ -82,6 +82,8 @@ class Command(BaseCommand):
                             help=_('maximum x coordinate, everthing right of it will be cropped'))
         parser.add_argument('--maxy', default=None, type=float,
                             help=_('maximum y coordinate, everthing above it will be cropped'))
+        parser.add_argument('--min-width', default=None, type=float,
+                            help=_('ensure that all objects are at least this thick'))
 
     def handle(self, *args, **options):
         (minx, miny), (maxx, maxy) = Source.max_bounds()
@@ -101,7 +103,8 @@ class Command(BaseCommand):
 
         for level in options['levels']:
             renderer = MapRenderer(level.pk, minx, miny, maxx, maxy, access_permissions=options['permissions'],
-                                   scale=options['scale'], full_levels=options['full_levels'])
+                                   scale=options['scale'], full_levels=options['full_levels'],
+                                   min_width=options['min_width'])
 
             filename = os.path.join(settings.RENDER_ROOT,
                                     'level_%s.%s' % (level.short_label, options['filetype']))

src/c3nav/mapdata/render/engines/base.py

@@ -30,7 +30,7 @@ class RenderEngine(ABC):
 
     # draw an svg image. supports pseudo-3D shadow-rendering
     def __init__(self, width: int, height: int, xoff=0, yoff=0, zoff=0,
-                 scale=1, buffer=0, background='#FFFFFF', center=True):
+                 scale=1, buffer=0, background='#FFFFFF', min_width=None, center=True):
         self.width = width
         self.height = height
         self.minx = xoff
@@ -40,6 +40,7 @@ class RenderEngine(ABC):
         self.orig_buffer = buffer
         self.buffer = int(math.ceil(buffer*self.scale))
         self.background = background
+        self.min_width = min_width
 
         self.maxx = self.minx + width / scale
         self.maxy = self.miny + height / scale

src/c3nav/mapdata/render/engines/openscad.py

@@ -248,6 +248,8 @@ class OpenSCADEngine(Base3DEngine):
                             if not obstacle.geom.intersects(self.bbox):
                                 continue
                             obstacle = obstacle.geom.buffer(0).buffer(0.01, join_style=JOIN_STYLE.mitre)
+                            if self.min_width:
+                                obstacle = obstacle.union(self._satisfy_min_width(obstacle)).buffer(0)
                             obstacle = obstacle.intersection(geometry_buffered)
                             if not obstacle.is_empty:
                                 had_height_obstacles = True
@@ -278,6 +280,8 @@ class OpenSCADEngine(Base3DEngine):
                             if not obstacle.geom.intersects(self.bbox):
                                 continue
                             obstacle = obstacle.geom.buffer(0).buffer(0.01, join_style=JOIN_STYLE.mitre)
+                            if self.min_width:
+                                obstacle = obstacle.union(self._satisfy_min_width(obstacle)).buffer(0)
                             obstacle = obstacle.intersection(geometry_buffered).intersection(self.bbox)
                             if not obstacle.is_empty:
                                 had_obstacles = True
@@ -289,6 +293,13 @@ class OpenSCADEngine(Base3DEngine):
                     if had_obstacles:
                         main_building_block.append(obstacles_block)
 
+            if self.min_width and geoms.on_top_of_id is None:
+                main_building_block.append(
+                    self._add_polygon('min width',
+                                      self._satisfy_min_width(buildings).intersection(self.bbox).buffer(0),
+                                      geoms.lower_bound, geoms.upper_bound)
+                )
+
     def _add_polygon(self, name, geometry, minz, maxz):
         geometry = geometry.buffer(0)
         polygons = []
@@ -340,5 +351,8 @@ class OpenSCADEngine(Base3DEngine):
         cmd = OpenScadBlock('translate([%f, %f, %f])' % (point1.x, point1.y, altitude1/1000), children=[cmd])
         return cmd
 
+    def _satisfy_min_width(self, geometry):
+        return geometry.buffer(self.min_width/2, join_style=JOIN_STYLE.mitre)
+
     def render(self, filename=None):
         return self.root.render().encode()

src/c3nav/mapdata/render/renderer.py

@@ -10,7 +10,8 @@ from c3nav.mapdata.render.utils import get_full_levels, get_min_altitude
 
 
 class MapRenderer:
-    def __init__(self, level, minx, miny, maxx, maxy, scale=1, access_permissions=None, full_levels=False):
+    def __init__(self, level, minx, miny, maxx, maxy, scale=1, access_permissions=None, full_levels=False,
+                 min_width=None):
         self.level = level.pk if isinstance(level, Level) else level
         self.minx = minx
         self.miny = miny
@@ -19,6 +20,7 @@ class MapRenderer:
         self.scale = scale
         self.access_permissions = set(access_permissions) if access_permissions else set()
         self.full_levels = full_levels
+        self.min_width = min_width/self.scale
 
         self.width = int(round((maxx - minx) * scale))
         self.height = int(round((maxy - miny) * scale))
@@ -36,7 +38,7 @@ class MapRenderer:
         level_render_data = LevelRenderData.get(self.level)
 
         engine = engine_cls(self.width, self.height, self.minx, self.miny, float(level_render_data.base_altitude),
-                            scale=self.scale, buffer=1, background='#DCDCDC', center=center)
+                            scale=self.scale, buffer=1, background='#DCDCDC', center=center, min_width=self.min_width)
 
         if hasattr(engine, 'custom_render'):
             engine.custom_render(level_render_data, access_permissions, self.full_levels)