use rtree for first filtering: use boost

airspace/parser.py

@@ -85,14 +85,25 @@ re_lines = [aclass,
 class ZoneIndex:
     def __init__(self):
         self.list = []
-        idx = Rtree()
+        self.rtree_idx = Rtree()
         self.idx = 0
 
     def append(self, zone):
-        self.idx.add(self.idx, zone.poly.GetEnvelope())
+        zone.finish()
+        minLong,maxLong,minLat,maxLat =  zone.poly.GetEnvelope()
+        bbox = (minLong, minLat, maxLong, maxLat)
+##        print "bbox: ", bbox
+        self.rtree_idx.add(self.idx, bbox)
         self.idx += 1
         self.list.append(zone)
-
+    
+    def __len__(self):
+        return len(self.list)
+
+    def intersection(self, bbox):
+        minLong,maxLong,minLat,maxLat = bbox
+        n_bbox = (minLong, minLat, maxLong, maxLat)
+        return [self.list[i] for i in self.rtree_idx.intersection(n_bbox)]
 
 class OAIRParser:
     """

airspace/zone.py

@@ -133,8 +133,10 @@ class PolyZone(Zone):
         """
         Closes the zone and returns the polygon
         """
-        self.ring.CloseRings()
-        self.poly.AddGeometry(self.ring)
+        if self.ring :
+            self.ring.CloseRings()
+            self.poly.AddGeometry(self.ring)
+            self.ring = None
 
         return self.poly
 

test-intersection-from-oair.py

@@ -40,7 +40,12 @@ found_an_intersection = 0
 
 intersected_segs = []
 
-for zone in p.zones:
+print "Track bbox: ", track.GetEnvelope()
+zones_to_check = p.zones.intersection(track.GetEnvelope())
+print "Potential crossed zones:", len(zones_to_check)
+
+for zone in zones_to_check:
+##for zone in p.zones.list:
     poly = zone.finish()
     if poly.Intersect(track):
         found_an_intersection += 1