map tile rendering base

src/c3nav/mapdata/render/__init__.py

@@ -0,0 +1 @@
+from c3nav.mapdata.render.svg import render_svg  # noqa

src/c3nav/mapdata/render/svg.py

@@ -0,0 +1,9 @@
+from c3nav.mapdata.utils.svg import SVGImage
+
+
+def render_svg(level, miny, minx, maxy, maxx, scale=1):
+    svg = SVGImage(bounds=((miny, minx), (maxy, maxx)), scale=scale)
+
+    # todo: render
+
+    return svg.get_xml()

src/c3nav/mapdata/urls.py

@@ -0,0 +1,7 @@
+from django.conf.urls import url
+
+from c3nav.mapdata.views import tile
+
+urlpatterns = [
+    url(r'^(?P<level>\d+)/(?P<zoom>\d+)/(?P<x>-?\d+)/(?P<y>-?\d+).(?P<format>png|svg)$', tile, name='mapdata.tile'),
+]

src/c3nav/mapdata/views.py

@@ -0,0 +1,40 @@
+import subprocess
+
+from django.http import Http404, HttpResponse
+from django.shortcuts import get_object_or_404
+from shapely.geometry import box
+
+from c3nav.mapdata.models import Level, Source
+from c3nav.mapdata.render import render_svg
+
+
+def tile(request, level, zoom, x, y, format):
+    zoom = int(zoom)
+    if not (0 <= zoom <= 10):
+        raise Http404
+
+    bounds = Source.max_bounds()
+
+    x, y = int(x), int(y)
+    size = 256/2**zoom
+    minx = size * x
+    miny = size * y
+    maxx = minx + size
+    maxy = miny + size
+
+    if not box(bounds[0][1], bounds[0][0], bounds[1][1], bounds[1][0]).intersects(box(minx, miny, maxx, maxy)):
+        raise Http404
+
+    level = get_object_or_404(Level, pk=level)
+
+    svg = render_svg(level, miny, minx, maxy, maxx, scale=2**zoom)
+
+    if format == 'svg':
+        response = HttpResponse(svg, 'image/svg+xml')
+    elif format == 'png':
+        p = subprocess.run(('rsvg-convert', '--format', 'png'), input=svg.encode(), stdout=subprocess.PIPE, check=True)
+        response = HttpResponse(p.stdout, content_type="image/png")
+    else:
+        raise ValueError
+
+    return response

src/c3nav/urls.py

@@ -6,11 +6,13 @@ from django.contrib import admin
 
 import c3nav.api.urls
 import c3nav.editor.urls
+import c3nav.mapdata.urls
 import c3nav.site.urls
 
 urlpatterns = [
     url(r'^editor/', include(c3nav.editor.urls)),
     url(r'^api/', include(c3nav.api.urls, namespace='api')),
+    url(r'^map/', include(c3nav.mapdata.urls)),
     url(r'^admin/', admin.site.urls),
     url(r'^locales/', include('django.conf.urls.i18n')),
     url(r'^', include(c3nav.site.urls)),