1 files changed, 20 insertions, 1 deletions
diff --git a/city/geometry.lua b/city/geometry.lua
index a24e508..e380173 100644
--- a/city/geometry.lua
+++ b/city/geometry.lua
@@ -89,7 +89,7 @@ geom.square = class{
 	 this(geom.point(x-d, y+d), d*2),
 	 this(geom.point(x+d, y+d), d*2),
       }
-   end
+   end,
 }
 
 
@@ -150,6 +150,25 @@ geom.qt_node = class{
 
       -- should never get here
       return false
+   end,
+
+   -- append any points within the supplied region under
+   -- the current node to the supplied array
+   query = function(self, region, points)
+      -- don't do anything if there's no intersection
+      if not self.square:intersects(region) then return end
+
+      if self:is_leaf() then
+	 if self.point and region:contains(self.point) then
+	    table.insert(points, self.point)
+	 end
+	 return
+      end
+
+      -- not a leaf node, recursively query children
+      for _, child in ipairs(self.children) do
+	 child:query(region, points)
+      end
    end
 }