PostGIS data backend

--HG--
rename : src/vtiles_backend.py => src/backend/vtile/__init__.py

src/__init__.py

@@ -0,0 +1 @@
+# -*- coding: utf-8 -*-

src/backend/__init__.py

@@ -0,0 +1 @@
+# -*- coding: utf-8 -*-

src/backend/postgis/__init__.py

@@ -0,0 +1,96 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+#    This file is part of kothic, the realtime map renderer.
+
+#   kothic is free software: you can redistribute it and/or modify
+#   it under the terms of the GNU General Public License as published by
+#   the Free Software Foundation, either version 3 of the License, or
+#   (at your option) any later version.
+
+#   kothic is distributed in the hope that it will be useful,
+#   but WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#   GNU General Public License for more details.
+
+#   You should have received a copy of the GNU General Public License
+#   along with kothic.  If not, see <http://www.gnu.org/licenses/>.
+
+#from debug import debug
+from twms import projections
+import psycopg2
+import shapely.wkb
+
+class Way:
+  def __init__(self, tags, geom):
+
+    self.cs = None
+    #print [x.split("=") for x in tags.split(";")]
+    self.tags = tags
+    # calculating center point
+    #c= geom
+    #sumz = [(c[0],c[1])]
+    #for k in range(2, len(c), 2):
+    #  sumz.append((c[k], c[k + 1]))
+    self.coords = geom
+    #  left for the better times:
+    self.center = reduce(lambda x, y: (x[0]+y[0],x[1]+y[1]), self.coords)
+    self.center = (self.center[0]/len(self.coords),self.center[1]/len(self.coords))
+    #debug(self.center)
+
+class PostGisBackend:
+  """
+  A class that gives out vector data on demand.
+  """
+  
+
+  def __init__(self,database = "dbname=gis user=mapz",max_zoom = 16,proj = "EPSG:3857", path = "tiles", lang = "ru", ):
+    
+    
+ #   debug("Bakend created")
+    self.database=database
+    self.max_zoom = max_zoom            # no better tiles available
+    self.path = path                    # path to tile files
+    self.lang = lang                    # map language to use
+    self.tiles = {}                     # loaded vector tiles go here
+    self.data_projection = proj         # which projection used to cut map in tiles
+    self.keep_tiles = 190                # a number of tiles to cache in memory
+    self.tile_load_log = []             # used when selecting which tile to unload
+    
+  def get_vectors (self, bbox, zoom):
+    a = psycopg2.connect(self.database)
+    b = a.cursor()
+    bbox = tuple(projections.from4326(bbox,self.data_projection))
+    ### FIXME: hardcoded EPSG:3857 in database
+    tables = ("planet_osm_line","planet_osm_polygon")  # FIXME: points
+    resp = {}
+    for table in tables:
+      b.execute("SELECT * FROM %s WHERE way && SetSRID('BOX3D(%s %s,%s %s)'::box3d,900913);"%(table,bbox[0],bbox[1],bbox[2],bbox[3]))
+      names = [q[0] for q in b.description]
+      for row in b.fetchall():
+        
+          row_dict = dict(map(None,names,row))
+          for k,v in row_dict.items():
+            if not v:
+              del row_dict[k]
+          geom = shapely.wkb.loads(row_dict["way"].decode('hex'))
+          ### FIXME: a dirty hack to basically support polygons, needs lots of rewrite
+          try:
+            geom = list(geom.coords)
+          except NotImplementedError:
+            "trying polygons"
+            try:
+              geom = geom.boundary
+              geom = list(geom.coords)
+            except NotImplementedError:
+              "multipolygon"
+              continue
+              ### FIXME
+          
+          geom = projections.to4326(geom, self.data_projection)
+          del row_dict["way"]
+          oid = row_dict["osm_id"]
+          del row_dict["osm_id"]
+          w = Way(row_dict, geom)
+          #print row_dict
+          resp[oid] = w
+    return resp

src/generate_image.py

@@ -17,7 +17,8 @@
 
 
 from debug import debug, Timer
-from vtiles_backend import QuadTileBackend as DataBackend
+#from backend.vtile import QuadTileBackend as DataBackend
+from backend.postgis import PostGisBackend as DataBackend
 #from style import Styling
 from mapcss import MapCSS
 
@@ -25,7 +26,7 @@ from render import RasterTile
 
 
 style = MapCSS(1, 19)     #zoom levels
-style.parse(open("styles/default.mapcss","r").read())
+style.parse(open("styles/openstreetinfo.mapcss","r").read())
 
 
 bbox = (27.115768874532,53.740327031764,28.028320754378,54.067187302158)

src/twms_fetcher.py

@@ -0,0 +1,51 @@
+# -*- coding: utf-8 -*-
+#    This file is part of tWMS.
+
+#   tWMS is free software: you can redistribute it and/or modify
+#   it under the terms of the GNU General Public License as published by
+#   the Free Software Foundation, either version 3 of the License, or
+#   (at your option) any later version.
+
+#   tWMS is distributed in the hope that it will be useful,
+#   but WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#   GNU General Public License for more details.
+
+#   You should have received a copy of the GNU General Public License
+#   along with tWMS.  If not, see <http://www.gnu.org/licenses/>.
+
+import StringIO
+import Image
+import os
+
+from twms import projections
+
+#from vtiles_backend import QuadTileBackend as DataBackend
+from backend.postgis import PostGisBackend as DataBackend
+from mapcss import MapCSS
+from render import RasterTile
+from tempfile import NamedTemporaryFile
+
+style = MapCSS(1,19)
+style.parse(open("/home/kom/osm/kothic/src/styles/openstreetinfo.mapcss","r").read())
+
+
+
+def kothic_fetcher (z, x, y, this_layer):
+   if "max_zoom" in this_layer:
+    if z >= this_layer["max_zoom"]:
+      return None   
+   bbox = projections.bbox_by_tile(z,x,y,"EPSG:3857")
+   db = DataBackend(path="/home/kom/osm/kothic/src/tiles")
+   res = RasterTile(256, 256, 1, db, "EPSG:3857")
+   res.update_surface(bbox, z, style)
+   f = NamedTemporaryFile()
+   f.close()
+   res.surface.write_to_png(f.name)
+   del res
+   del db
+   im = Image.open(f.name)
+   os.unlink(f.name)
+   im = im.convert("RGBA")
+
+   return im