Refactor map generator package

- Move room generators to map.generators.room
- Move corridor generators to map.generators.corridor

Generators have a generate() method that generates the things they place,
and an apply() method that applies their objects to a grid of tiles.

erynrl/map/room.py

@@ -0,0 +1,58 @@
+from typing import Iterator
+
+from ..geometry import Point, Rect
+
+
+class Room:
+    '''An abstract room. It can be any size or shape.'''
+
+    def __init__(self, bounds):
+        self.bounds = bounds
+
+    @property
+    def center(self) -> Point:
+        '''The center of the room, truncated according to integer math rules'''
+        return self.bounds.midpoint
+
+    @property
+    def walls(self) -> Iterator[Point]:
+        '''An iterator over all the wall tiles of this room.'''
+        raise NotImplementedError()
+
+    @property
+    def walkable_tiles(self) -> Iterator[Point]:
+        '''An iterator over all the walkable tiles in this room.'''
+        raise NotImplementedError()
+
+
+class RectangularRoom(Room):
+    '''A rectangular room defined by a Rect.
+
+    Attributes
+    ----------
+    bounds : Rect
+        A rectangle that defines the room. This rectangle includes the tiles used for the walls, so the floor is 1 tile
+        inset from the bounds.
+    '''
+
+    @property
+    def walkable_tiles(self) -> Iterator[Point]:
+        floor_rect = self.bounds.inset_rect(top=1, right=1, bottom=1, left=1)
+        for y in range(floor_rect.min_y, floor_rect.max_y + 1):
+            for x in range(floor_rect.min_x, floor_rect.max_x + 1):
+                yield Point(x, y)
+
+    @property
+    def walls(self) -> Iterator[Point]:
+        bounds = self.bounds
+        min_y = bounds.min_y
+        max_y = bounds.max_y
+        min_x = bounds.min_x
+        max_x = bounds.max_x
+        for y in range(min_y, max_y + 1):
+            for x in range(min_x, max_x + 1):
+                if y == min_y or y == max_y or x == min_x or x == max_x:
+                    yield Point(x, y)
+
+    def __repr__(self) -> str:
+        return f'{self.__class__.__name__}({self.bounds})'