Center display around our hero(es)
[koperkapel.git] / koperkapel / scenes / level.py
1 """Render a level"""
2
3 from pgzero.constants import keys
4 from pygame import Surface
5 import pygame.locals as pgl
6 from ..loaders.levelloader import levels
7 from .base import Scene, ChangeSceneEvent, MoveViewportEvent
8 from ..constants import TILE_SIZE, WIDTH, HEIGHT
9 from ..roaches import default_roaches
10
11
12 class BaseLevelScene(Scene):
13     """ Level scene. """
14
15     def enter(self, world):
16         self._level = levels.load(world.level.name)
17         self._tiles = self._level.tiles
18         self._level_layer = 'floor'
19         self._surfaces = {}
20         self._overlay = {}
21         for layer in ['floor', 'tunnels']:
22             self._surfaces[layer] = self._render(layer)
23         self._overlay = self._surfaces['floor'].copy()
24
25     def _render(self, layer):
26         # We cache the rendered surface to avoid doing a large number
27         # of blits each frame, as that introduces a large performance
28         # overhead.
29         surface = Surface((len(self._tiles[0]) * TILE_SIZE,
30                            len(self._tiles) * TILE_SIZE))
31         layer_key = '%s image' % layer
32         for y, row in enumerate(self._tiles):
33             for x, tile in enumerate(row):
34                 pos = (x * TILE_SIZE, y * TILE_SIZE)
35                 if layer_key not in tile:
36                     # Skip broken tiles for now
37                     continue
38                 surface.blit(tile[layer_key], pos)
39         return surface.convert_alpha()
40
41     def draw(self, screen, viewport):
42         screen.clear()
43         # Viewport is the position of the screen relative to the
44         # surface. We need the position of the surface relative to
45         # the screen for the blit, so this conversion
46         screen.surface.blit(self._surfaces[self._level_layer], (0, 0),
47                             area=(viewport[0], viewport[1], WIDTH, HEIGHT))
48         if self._level_layer != 'floor':
49             screen.surface.blit(self._overlay, (0, 0),
50                          area=(viewport[0], viewport[1], WIDTH, HEIGHT), 
51                          special_flags=pgl.BLEND_MULT)
52         self.actors.draw(screen)
53
54     def on_key_down(self, key, mod, unicode):
55         if key == keys.ESCAPE:
56             from .menu import MenuScene
57             return [ChangeSceneEvent(MenuScene())]
58
59
60 class GameLevelScene(BaseLevelScene):
61
62     def enter(self, world):
63         super().enter(world)
64         self._roaches = self.actors.add_layer("roaches", level=10)
65         return self._init_roaches(world.roaches)
66
67     def _init_roaches(self, roaches):
68         for roach in roaches:
69             roach_actor = self._roaches.add(default_roaches.assemble(roach))
70             roach_actor.anchor = (0, 0)
71             roach_actor.pos = (WIDTH // 2, HEIGHT // 2)
72         x, y = self._level.start_pos
73         self._set_pos(x, y)
74         self._level_layer = 'floor'
75         # Fix viewport offset
76         return [MoveViewportEvent((x * TILE_SIZE - WIDTH // 2, y * TILE_SIZE - HEIGHT // 2))]
77
78     def _set_pos(self, x, y):
79         self._player_pos = (x, y)
80
81     def on_key_down(self, key, mod, unicode):
82         offset = None
83         x, y = self._player_pos
84         if key == keys.DOWN:
85             if self._level.can_walk(x, y + 1, self._level_layer):
86                 self._set_pos(x, y + 1)
87                 offset = (0, TILE_SIZE)
88         elif key == keys.UP:
89             if self._level.can_walk(x, y - 1, self._level_layer):
90                 self._set_pos(x, y - 1)
91                 offset = (0, -TILE_SIZE)
92         elif key == keys.LEFT:
93             if self._level.can_walk(x - 1, y, self._level_layer):
94                 self._set_pos(x - 1, y)
95                 offset = (-TILE_SIZE, 0)
96         elif key == keys.RIGHT:
97             if self._level.can_walk(x + 1, y, self._level_layer):
98                 self._set_pos(x + 1, y)
99                 offset = (TILE_SIZE, 0)
100         elif key == keys.S:
101             if self._level_layer == 'floor':
102                 if self._level.can_walk(x, y, 'tunnels'):
103                     self._level_layer = 'tunnels'
104             elif self._level.can_walk(x, y, 'floor'):
105                 # Must be in the tunnels already
106                 self._level_layer = 'floor'
107             return
108         if offset:
109             return [MoveViewportEvent(offset)]
110         return super(GameLevelScene, self).on_key_down(key, mod, unicode)
111         
112