Use shapely projection instead of brute force.

Converts the landmap to use MultiPolygon instead of a collection of
polygons, since Shapely has explicit support for this.

Because we've done that, we can use a single projection from a line
instead of brute forcing the extent of the front line.

This makes turn processing ~66% faster (3 seconds to 1.8).

There are probably other places this should be used.

game/theater/conflicttheater.py

@@ -447,11 +447,11 @@ class ConflictTheater:
         if self.is_on_land(point):
             return False
 
-        for exclusion_zone in self.landmap[1]:
+        for exclusion_zone in self.landmap.exclusion_zones:
             if poly_contains(point.x, point.y, exclusion_zone):
                 return False
 
-        for sea in self.landmap[2]:
+        for sea in self.landmap.sea_zones:
             if poly_contains(point.x, point.y, sea):
                 return True
 
@@ -462,14 +462,13 @@ class ConflictTheater:
             return True
 
         is_point_included = False
-        for inclusion_zone in self.landmap[0]:
-            if poly_contains(point.x, point.y, inclusion_zone):
-                is_point_included = True
+        if poly_contains(point.x, point.y, self.landmap.inclusion_zones):
+            is_point_included = True
 
         if not is_point_included:
             return False
 
-        for exclusion_zone in self.landmap[1]:
+        for exclusion_zone in self.landmap.exclusion_zones:
             if poly_contains(point.x, point.y, exclusion_zone):
                 return False
 
@@ -484,7 +483,7 @@ class ConflictTheater:
         nearest_points = []
         if not self.landmap:
             raise RuntimeError("Landmap not initialized")
-        for inclusion_zone in self.landmap[0]:
+        for inclusion_zone in self.landmap.inclusion_zones:
             nearest_pair = ops.nearest_points(point, inclusion_zone)
             nearest_points.append(nearest_pair[1])
         min_distance = point.distance(nearest_points[0]) # type: geometry.Point

game/theater/landmap.py

@@ -1,11 +1,17 @@
+from dataclasses import dataclass
 import pickle
-from typing import Collection, Optional, Tuple
+from typing import Optional, Tuple, Union
 import logging
 
 from shapely import geometry
+from shapely.geometry import MultiPolygon, Polygon
 
-Zone = Collection[Tuple[float, float]]
-Landmap = Tuple[Collection[geometry.Polygon], Collection[geometry.Polygon], Collection[geometry.Polygon]]
+
+@dataclass(frozen=True)
+class Landmap:
+    inclusion_zones: MultiPolygon
+    exclusion_zones: MultiPolygon
+    sea_zones: MultiPolygon
 
 
 def load_landmap(filename: str) -> Optional[Landmap]:
@@ -17,7 +23,7 @@ def load_landmap(filename: str) -> Optional[Landmap]:
         return None
 
 
-def poly_contains(x, y, poly:geometry.Polygon):
+def poly_contains(x, y, poly: Union[MultiPolygon, Polygon]):
     return poly.contains(geometry.Point(x, y))