start of new blender render engine

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

@@ -0,0 +1,87 @@
+import re
+
+from shapely.ops import unary_union
+
+from c3nav.mapdata.render.engines import register_engine
+from c3nav.mapdata.render.engines.base3d import Base3DEngine
+from c3nav.mapdata.render.utils import get_full_levels, get_min_altitude
+from c3nav.mapdata.utils.geometry import assert_multipolygon
+
+
+@register_engine
+class BlenderEngine(Base3DEngine):
+    filetype = 'blend.py'
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.result = ''
+        self._add_python('''
+            def add_polygon(exterior, interiors, minz, maxz):
+                add_ring(exterior, minz, maxz)
+
+            def add_ring(coords, minz, maxz):
+                if coords[0] == coords[-1]:
+                    coords = coords[:-1]
+                if len(coords) < 3:
+                    raise ValueError('Ring with less than 3 points.')
+                indices = tuple(range(len(coords)))
+                mesh = bpy.data.meshes.new(name='Test')
+                mesh.from_pydata(
+                    tuple((x, y, minz) for x, y in coords),
+                    tuple(zip(indices, indices[1:]+(0, ))),
+                    (indices, ),
+                )
+                obj = bpy.data.objects.new('Test', mesh)
+                scene = bpy.context.scene
+                scene.objects.link(obj)
+                return obj
+        ''')
+
+    def _clean_python(self, code):
+        if '\t' in code:
+            raise ValueError('Tabulators in code')
+        code = re.sub(r'^( *\n)*', '', code)
+        whitespaces = re.match('^ *', code)
+        code = re.sub(r'^%s' % whitespaces.group(0), '', code, flags=re.MULTILINE)
+        code = re.sub(r'^ +$', '', code, flags=re.MULTILINE)
+        code = re.sub(r' +$', '', code)
+        return code
+
+    def _add_python(self, code):
+        self.result += self._clean_python(code)+'\n'
+
+    def custom_render(self, level_render_data, bbox, access_permissions):
+        levels = get_full_levels(level_render_data)
+        min_altitude = get_min_altitude(levels, default=level_render_data.base_altitude)
+        print(min_altitude)
+        for level in levels:
+            print(level)
+
+        for geoms in levels:
+            # hide indoor and outdoor rooms if their access restriction was not unlocked
+            restricted_spaces_indoors = unary_union(
+                tuple(area.geom for access_restriction, area in geoms.restricted_spaces_indoors.items()
+                      if access_restriction not in access_permissions)
+            )
+            restricted_spaces_outdoors = unary_union(
+                tuple(area.geom for access_restriction, area in geoms.restricted_spaces_outdoors.items()
+                      if access_restriction not in access_permissions)
+            )
+            restricted_spaces = unary_union((restricted_spaces_indoors, restricted_spaces_outdoors))  # noqa
+
+            for altitudearea in geoms.altitudeareas:
+                self._add_polygon(altitudearea.geometry.geom)
+                break
+
+            break
+
+    def _add_polygon(self, geometry):
+        for polygon in assert_multipolygon(geometry):
+            self._add_python('add_polygon(exterior=%(exterior)r, interiors=%(interiors)r, minz=0, maxz=1)' % {
+                'exterior': tuple(polygon.exterior.coords),
+                'interiors': tuple(tuple(interior.coords) for interior in polygon.interiors),
+            })
+            continue
+
+    def render(self, filename=None):
+        return self.result.encode()