bulletml/impl.py

   1 """BulletML implementation.
   2
   3 http://www.asahi-net.or.jp/~cs8k-cyu/bulletml/index_e.html
   4 """
   5
   6 from __future__ import division
   7
   8 import math
   9
  10 from bulletml import parser
  11
  12 # TODO(jfw): This is very non-Pythonic, it's pretty much just the
  13 # BulletML reference ActionImpl translated to Python.
  14
  15 class Action(object):
  16     """Running action implementation."""
  17
  18     def __init__(self, owner, parent, actions, params, rank):
  19         self.actions = actions
  20         self.parent = parent
  21         self.repeat = 1
  22         self.wait_frames = 0
  23         self.speed = 0
  24         self.speed_frames = 0
  25         self.aim_direction = 0
  26         self.direction = 0
  27         self.direction_frames = 0
  28         self.aiming = False
  29         self.aim_mx = 0
  30         self.aim_my = 0
  31         self.mx = 0
  32         self.my = 0
  33         self.owner = owner
  34         self.accel_frames = 0
  35         self.previous_fire_direction = 0
  36         self.previous_fire_speed = 0
  37         self.params = params
  38         self.rank = rank
  39         self.pc = -1
  40         if parent:
  41             self.copy_state(parent)
  42
  43     def __repr__(self):
  44         return "%s(pc=%r, actions=%r)" % (
  45             type(self).__name__, self.pc, self.actions)
  46
  47     @property
  48     def finished(self):
  49         return self.pc is None
  50
  51     def vanish(self):
  52         if self.parent:
  53             self.parent.vanish()
  54         self.pc = None
  55
  56     def copy_state(self, other):
  57         self.direction_frames = other.direction_frames
  58         self.direction = other.direction
  59         self.aiming = other.aiming
  60         self.speed_frames = other.speed_frames
  61         self.speed = other.speed
  62         self.accel_frames = other.accel_frames
  63         self.mx = other.mx
  64         self.my = other.my
  65         self.previous_fire_direction = other.previous_fire_direction
  66         self.previous_fire_speed = other.previous_fire_speed
  67
  68     def step(self):
  69         created = []
  70
  71         if self.speed_frames > 0:
  72             self.speed_frames -= 1
  73             self.owner.speed += self.speed
  74
  75         if self.direction_frames > 0:
  76             self.direction_frames -= 1
  77             if self.direction_frames <= 0:
  78                 if self.aiming:
  79                     self.owner.direction += self.owner.aim
  80             else:
  81                 self.owner.direction += self.direction
  82
  83         if self.accel_frames > 0:
  84             self.accel_frames -= 1
  85             self.owner.mx += self.mx
  86             self.owner.my += self.my
  87
  88         if self.pc is None:
  89             return created
  90
  91         if self.wait_frames > 0:
  92             self.wait_frames -= 1
  93             return created
  94
  95         while True:
  96             self.pc += 1
  97
  98             if self.pc >= len(self.actions):
  99                 self.repeat -= 1
 100                 if self.repeat <= 0:
 101                     self.pc = None
 102                     if self.parent is not None:
 103                         self.parent.copy_state(self)
 104                         self.owner.replace(self, self.parent)
 105                     break
 106                 else:
 107                     self.pc = 0
 108
 109             action = self.actions[self.pc]
 110
 111             if isinstance(action, parser.Repeat):
 112                 repeat, (actions, params) = action(self.params, self.rank)
 113                 child = Action(self.owner, self, actions, params, self.rank)
 114                 child.repeat = repeat
 115                 self.owner.replace(self, child)
 116                 created.extend(child.step())
 117                 break
 118
 119             elif isinstance(action, (parser.ActionDef, parser.ActionRef)):
 120                 actions, params = action(self.params, self.rank)
 121                 child = Action(self.owner, self, actions, params, self.rank)
 122                 self.owner.replace(self, child)
 123                 created.extend(child.step())
 124                 break
 125
 126             elif isinstance(action, (parser.FireDef, parser.FireRef)):
 127                 direction, speed, actions = action(self.params, self.rank)
 128                 if direction:
 129                     direction, type = direction
 130                     if type == "aim" or type is None:
 131                         direction += self.owner.aim
 132                     elif type == "sequence":
 133                         direction += self.previous_fire_direction
 134                     elif type == "relative":
 135                         direction += self.owner.direction
 136                 else:
 137                     direction = self.owner.aim
 138                 self.previous_fire_direction = direction
 139
 140
 141                 if speed:
 142                     speed, type = speed
 143                     if type == "sequence":
 144                         speed += self.previous_fire_speed
 145                     elif type == "relative":
 146                         # FIXME(jfw): Reference impl uses prvFireSpeed
 147                         # here?  That doesn't seem right at all.
 148                         speed += self.owner.speed
 149                 else:
 150                     speed = 1
 151                 self.previous_fire_speed = speed
 152
 153                 bullet = Bullet(self.owner.x, self.owner.y, direction, speed,
 154                                 self.owner.target, actions, self)
 155                 created.append(bullet)
 156
 157             elif isinstance(action, parser.ChangeSpeed):
 158                 frames, (speed, type) = action(self.params, self.rank)
 159                 self.speed_frames = frames
 160                 if type == "sequence":
 161                     self.speed = speed
 162                 elif type == "relative":
 163                     self.speed = speed / frames
 164                 else:
 165                     self.speed = (speed - self.owner.speed) / frames
 166
 167             elif isinstance(action, parser.ChangeDirection):
 168                 frames, (direction, type) = action(self.params, self.rank)
 169                 self.direction_frames = frames
 170                 self.aiming = False
 171                 if type == "sequence":
 172                     self.aiming = False
 173                     self.direction = direction
 174                 else:
 175                     if type == "absolute":
 176                         self.aiming = False
 177                         self.direction = (
 178                             direction - self.owner.direction) % 360
 179                     elif type == "relative":
 180                         self.aiming = False
 181                         self.direction = direction
 182                     else:
 183                         self.aiming = True
 184                         self.direction = (
 185                             direction
 186                             + self.owner.aim
 187                             - self.owner.direction) % 360
 188
 189                     while self.direction > 180:
 190                         self.direction -= 360
 191                     while self.direction < -180:
 192                         self.direction += 360
 193                     self.direction /= self.direction_frames
 194
 195             elif isinstance(action, parser.Accel):
 196                 frames, horizontal, vertical = action(self.params, self.rank)
 197                 self.accel_frames = frames
 198                 if horizontal:
 199                     mx, type = horizontal
 200                     if type == "sequence":
 201                         self.mx = mx
 202                     elif type == "absolute":
 203                         self.mx = (mx - self.owner.mx) / frames
 204                     elif type == "relative":
 205                         self.mx = mx / frames
 206                 if vertical:
 207                     my, type = vertical
 208                     if type == "sequence":
 209                         self.my = my
 210                     elif type == "absolute":
 211                         self.my = (my - self.owner.my) / frames
 212                     elif type == "relative":
 213                         self.my = my / frames
 214
 215             elif isinstance(action, parser.Wait):
 216                 self.wait_frames = action(self.params, self.rank)
 217                 break
 218
 219             elif isinstance(action, parser.Vanish):
 220                 self.owner.vanish()
 221                 break
 222
 223         return created
 224
 225 class Bullet(object):
 226     """Simple bullet implementation."""
 227
 228     def __init__(self, x=0, y=0, direction=0, speed=0, target=None,
 229                  actions=(), parent=None, rank=None):
 230         self.x = self.px = x
 231         self.y = self.py = y
 232         self.mx = 0
 233         self.my = 0
 234         self.direction = direction
 235         self.speed = speed
 236         self.vanished = False
 237         self.target = target
 238         self.actions = []
 239         if rank is None:
 240             rank = parent.rank if parent else 0.5
 241         # New bullets reset the parent hierarchy.
 242         self.actions = [Action(self, None, action, params, rank)
 243                         for action, params in actions]
 244
 245     def __repr__(self):
 246         return ("%s(%r, %r, accel=%r, direction=%r, speed=%r, "
 247                 "actions=%r, target=%r, vanished=%r)") % (
 248             type(self).__name__, self.x, self.y, (self.mx, self.my),
 249             self.direction, self.speed, self.actions, self.target,
 250             self.vanished)
 251
 252     @property
 253     def aim(self):
 254         """Angle to the target."""
 255         if self.target is None:
 256             return self.direction
 257         else:
 258             return math.degrees(
 259                 math.atan2(self.target.x - self.x, self.y - self.target.y))
 260
 261     @property
 262     def finished(self):
 263         for action in self.actions:
 264             if not action.finished:
 265                 return False
 266         return self.vanished
 267
 268     def vanish(self):
 269         """Vanish this bullet and stop all actions."""
 270         self.vanished = True
 271         for action in self.actions:
 272             action.vanish()
 273         self.actions = []
 274
 275     def replace(self, old, new):
 276         try:
 277             idx = self.actions.index(old)
 278         except ValueError:
 279             pass
 280         else:
 281             self.actions[idx] = new
 282
 283     def step(self):
 284         created = []
 285
 286         for action in self.actions:
 287             created.extend(action.step())
 288
 289         direction = math.radians(self.direction)
 290         self.px = self.x
 291         self.py = self.y
 292         self.x += self.mx + math.sin(direction) * self.speed
 293         self.y += self.my - math.cos(direction) * self.speed
 294
 295         return created
 296
 297     @classmethod
 298     def FromDoc(cls, doc, params=(), x=0, y=0, speed=0, direction=0,
 299                 target=None, rank=0.5):
 300         """Construct a bullet from top-level actions in a document."""
 301         actions = [act(params, rank) for act in doc.top]
 302         return cls(x, y, direction, speed, target, actions, rank=rank)
 303