Merge branch 'small-fixes' into 'master'

Small fixes

See merge request tdde25-2020/tdde25-2020-projekt-sg3-maps-05!18

1 files changed, 26 insertions, 25 deletions

diff --git a/algorithms.py b/algorithms.py
index 9f3fd78..8c63968 100644
--- a/algorithms.py
+++ b/algorithms.py
@@ -1,8 +1,14 @@
 import heapq
 import math
+import store
 
 
 def length_haversine(p1, p2):
+    """
+    The distance in meters between two coordinates on a sphere.
+
+    Assumes p1=(lat1, lng1) and p2=(lat2, lng2) in degrees.
+    """
     lat1 = p1.lat
     lng1 = p1.lng
     lat2 = p2.lat
@@ -10,67 +16,62 @@ def length_haversine(p1, p2):
     lat1, lng1, lat2, lng2 = map(math.radians, [lat1, lng1, lat2, lng2])
     dlat = lat2 - lat1
     dlng = lng2 - lng1
-    a = math.sin(dlat / 2) ** 2 + math.cos(lat1) * math.cos(lat2) * math.sin(
-        dlng / 2) ** 2
+    a = math.sin(dlat / 2) ** 2 + math.cos(lat1) * math.cos(lat2) * math.sin(dlng / 2) ** 2
     c = 2 * math.asin(math.sqrt(a))
 
     return 6372797.560856 * c  # return the distance in meters
 
 
-def grid_search(grid, source_node):
+def grid_search(grid, lat, lng):
     """
     Finds closest node to source node by comparing distance to nodes within
     nearest tiles in the grid.
     """
-    closest_nodes = []
-
-    source_key = (int(round(source_node.lat, 3) * 1000), int(round(
-        source_node.lng, 3) * 1000))
-
-    closest_tiles = find_nodes(0, grid, source_key)
-
-    for tile_nodes in closest_tiles:
-        closest_nodes.append(get_closest_node(tile_nodes, source_node))
-
+    source_node = store.Node(-1, lat, lng)
+    source_key = (
+            int(round(source_node.lat, 3) * 1000),
+            int(round(source_node.lng, 3) * 1000),
+    )
+
+    closest_tiles = find_nodes(grid, source_key)
+    closest_nodes = [get_closest_node(tile_nodes, source_node)
+                     for tile_nodes in closest_tiles]
     closest_node_id = get_closest_node(closest_nodes, source_node).id
-
     return closest_node_id
 
 
-def find_nodes(offset, grid, source_key):
+def find_nodes(grid, source_key, offset=0):
     """
     Searches a grid in an outward "spiral" from source node fetching all tiles
     which contain nodes.
     """
     tiles = None
 
+    # search further out until we find nodes
     while not tiles:
-        tiles = look_for_nodes(offset, grid, source_key)
+        tiles = look_for_nodes(grid, source_key, offset)
         offset += 1
 
-    return tiles + look_for_nodes(offset + 1, grid, source_key)
+    # include another layer since they might contain closer nodes
+    return tiles + look_for_nodes(grid, source_key, offset + 1)
 
 
-def look_for_nodes(offset, grid, source_key):
-    """Search for nearest tile containing nodes in an outward spiral."""
+def look_for_nodes(grid, source_key, offset):
+    """Search for nearest tile containing nodes in a spiral."""
     tiles = []
     for i in range(-offset, offset + 1):
         for j in range(-offset, offset + 1):
-
             if i in (-offset, offset) or j in (-offset, offset):
-
                 key = (source_key[0] + j, source_key[1] + i)
-
                 if key in grid.keys():
                     tiles.append(grid[key])
-
     return tiles
 
 
 def get_closest_node(nodes, source_node):
     """
-    Searches through all nodes in a specified grid and return node
-    closes to source node.
+    Search through all nodes in a specified grid and return the node
+    closest to source_node.
     """
     min_node = None
     min_value = None