Mercurial > nagslang
annotate nagslang/enemies.py @ 217:d98daba73055
Composition-based renderers.
| author | Jeremy Thurgood <firxen@gmail.com> |
|---|---|
| date | Wed, 04 Sep 2013 14:53:37 +0200 |
| parents | 3d54fe7a2998 |
| children | 9e2ef2f15035 |
| rev | line source |
|---|---|
| 168 | 1 import pymunk |
| 2 import pymunk.pygame_util | |
| 3 | |
| 207 | 4 from nagslang import render |
| 168 | 5 from nagslang.constants import COLLISION_TYPE_ENEMY, ZORDER_MID |
| 207 | 6 from nagslang.game_object import GameObject, SingleShapePhysicser, make_body |
| 168 | 7 from nagslang.mutators import FLIP_H |
| 8 from nagslang.resources import resources | |
| 9 | |
| 10 | |
| 11 class Enemy(GameObject): | |
| 12 """A base class for mobile enemies""" | |
| 13 | |
| 14 def __init__(self, space, position): | |
| 15 self._setup_physics(space, position) | |
| 16 self._setup_renderer() | |
| 17 | |
| 18 super(Enemy, self).__init__( | |
| 19 self._physicser, self.renderer) | |
| 20 self.zorder = ZORDER_MID | |
| 21 | |
| 22 def _get_image(self, name, *transforms): | |
| 23 return resources.get_image('creatures', name, transforms=transforms) | |
| 24 | |
| 25 def _setup_physics(self, space, position): | |
| 26 raise NotImplementedError | |
| 27 | |
| 28 def _setup_renderer(self): | |
| 29 raise NotImplementedError | |
| 30 | |
| 31 def attack(self): | |
| 32 raise NotImplementedError | |
| 33 | |
| 34 | |
| 35 class PatrollingAlien(Enemy): | |
| 36 | |
| 37 def __init__(self, space, position, end_position): | |
| 38 # An enemy that patrols between the two points | |
| 39 super(PatrollingAlien, self).__init__(space, position) | |
| 40 self._start_pos = position | |
| 41 self._end_pos = end_position | |
| 42 self._direction = 'away' | |
| 43 | |
| 44 def _setup_physics(self, space, position): | |
|
208
3d54fe7a2998
Fun with mass and friction.
Jeremy Thurgood <firxen@gmail.com>
parents:
207
diff
changeset
|
45 self._body = make_body(10, pymunk.inf, position, 0.8) |
| 168 | 46 |
| 47 self._shape = pymunk.Circle(self._body, 30) | |
| 48 | |
| 49 self._shape.elasticity = 1.0 | |
|
208
3d54fe7a2998
Fun with mass and friction.
Jeremy Thurgood <firxen@gmail.com>
parents:
207
diff
changeset
|
50 self._shape.friction = 0.05 |
| 168 | 51 self._shape.collision_type = COLLISION_TYPE_ENEMY |
| 52 self._physicser = SingleShapePhysicser(space, self._shape) | |
| 53 self.impulse_factor = 50 | |
| 54 self.angle = 0 | |
| 55 | |
| 56 def _setup_renderer(self): | |
|
217
d98daba73055
Composition-based renderers.
Jeremy Thurgood <firxen@gmail.com>
parents:
208
diff
changeset
|
57 self.renderer = render.FacingSelectionRenderer({ |
|
d98daba73055
Composition-based renderers.
Jeremy Thurgood <firxen@gmail.com>
parents:
208
diff
changeset
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58 'left': render.TimedAnimatedRenderer( |
|
d98daba73055
Composition-based renderers.
Jeremy Thurgood <firxen@gmail.com>
parents:
208
diff
changeset
|
59 [self._get_image('alien_A_1.png'), |
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d98daba73055
Composition-based renderers.
Jeremy Thurgood <firxen@gmail.com>
parents:
208
diff
changeset
|
60 self._get_image('alien_A_2.png')], 3), |
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d98daba73055
Composition-based renderers.
Jeremy Thurgood <firxen@gmail.com>
parents:
208
diff
changeset
|
61 'right': render.TimedAnimatedRenderer( |
|
d98daba73055
Composition-based renderers.
Jeremy Thurgood <firxen@gmail.com>
parents:
208
diff
changeset
|
62 [self._get_image('alien_A_1.png', FLIP_H), |
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d98daba73055
Composition-based renderers.
Jeremy Thurgood <firxen@gmail.com>
parents:
208
diff
changeset
|
63 self._get_image('alien_A_2.png', FLIP_H)], 3), |
|
d98daba73055
Composition-based renderers.
Jeremy Thurgood <firxen@gmail.com>
parents:
208
diff
changeset
|
64 }) |
| 168 | 65 |
| 66 def get_render_angle(self): | |
| 67 return self.angle | |
| 68 | |
| 69 def _switch_direction(self): | |
| 70 if self._direction == 'away': | |
| 71 self._direction = 'towards' | |
| 72 else: | |
| 73 self._direction = 'away' | |
| 74 | |
| 75 def set_direction(self, dx, dy): | |
| 76 self.angle = pymunk.Vec2d((dx, dy)).angle | |
| 77 self._body.apply_impulse( | |
| 78 (dx * self.impulse_factor, dy * self.impulse_factor)) | |
| 79 | |
| 80 def animate(self): | |
| 81 # Calculate the step every frame | |
| 82 if self._direction == 'away': | |
| 83 target = self._end_pos | |
| 84 else: | |
| 85 target = self._start_pos | |
| 86 x_step = 0 | |
| 87 y_step = 0 | |
| 88 if (target[0] < self._body.position[0]): | |
| 89 x_step = max(-1, target[0] - self._body.position[0]) | |
| 90 elif (target[0] > self._body.position[0]): | |
| 91 x_step = min(1, target[0] - self._body.position[0]) | |
| 92 if abs(x_step) < 0.5: | |
| 93 x_step = 0 | |
| 94 if (target[1] < self._body.position[1]): | |
| 95 y_step = max(-1, target[1] - self._body.position[1]) | |
| 96 elif (target[1] > self._body.position[1]): | |
| 97 y_step = min(1, target[1] - self._body.position[1]) | |
| 98 if abs(y_step) < 0.5: | |
| 99 y_step = 0 | |
| 100 if abs(x_step) < 1 and abs(y_step) < 1: | |
| 101 self._switch_direction() | |
| 102 self.set_direction(x_step, y_step) | |
| 103 super(PatrollingAlien, self).animate() |