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, errors
  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 = 0
  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 vanish(self):
  44         if self.parent:
  45             self.parent.vanish()
  46         self.repeat = 0
  47         self.pc = None
  48
  49     def copy_state(self, other):
  50         self.direction_frames = other.direction_frames
  51         self.direction = other.direction
  52         self.aiming = other.aiming
  53         self.speed_frames = other.speed_frames
  54         self.speed = other.speed
  55         self.accel_frames = other.accel_frames
  56         self.mx = other.mx
  57         self.my = other.my
  58         self.previous_fire_direction = other.previous_fire_direction
  59         self.previous_fire_speed = other.previous_fire_speed
  60
  61     def step(self):
  62         created = []
  63
  64         if self.speed_frames > 0:
  65             self.speed_frames -= 1
  66             self.owner.speed += self.speed
  67         if self.direction_frames > 0:
  68             self.direction_frames -= 1
  69             if self.direction_frames <= 0:
  70                 if self.aiming:
  71                     self.owner.direction += self.owner.aim
  72             else:
  73                 self.owner.direction += self.direction
  74         if self.accel_frames > 0:
  75             self.accel_frames -= 1
  76             self.owner.mx += self.mx
  77             self.owner.my += self.my
  78
  79         if self.pc is None:
  80             return created
  81
  82         if self.wait_frames > 0:
  83             self.wait_frames -= 1
  84             return created
  85
  86         while True:
  87             self.pc += 1
  88             if self.pc >= len(self.actions):
  89                 self.repeat -= 1
  90                 if self.repeat <= 0:
  91                     if self.parent is not None:
  92                         self.parent.copy_state(self)
  93                         self.owner.replace(self, self.parent)
  94                     break
  95                 else:
  96                     self.pc = 0
  97
  98             action = self.actions[self.pc]
  99
 100             if isinstance(action, parser.Repeat):
 101                 repeat, (actions, params) = action(self.params, self.rank)
 102                 child = Action(self.owner, self, actions, params, self.rank)
 103                 child.repeat = repeat
 104                 self.owner.replace(self, child)
 105                 created.extend(child.step())
 106                 break
 107
 108             elif isinstance(action, (parser.ActionDef, parser.ActionRef)):
 109                 action, params = action(self.params, self.rank)
 110                 child = Action(self.owner, self, actions, params, self.rank)
 111                 self.owner.replace(self, child)
 112                 created.extend(child.step())
 113                 break
 114
 115             elif isinstance(action, (parser.FireDef, parser.FireRef)):
 116                 direction, speed, actions = action(self.params, self.rank)
 117                 if direction:
 118                     direction, type = direction
 119                     if type == "aim":
 120                         direction += self.owner.aim
 121                     elif type == "sequence":
 122                         direction += self.previous_fire_direction
 123                     elif type == "relative":
 124                         direction += self.owner.direction
 125                 else:
 126                     direction = self.owner.aim
 127                 self.previous_fire_direction = direction
 128
 129
 130                 if speed:
 131                     speed, type = speed
 132                     if type == "sequence":
 133                         speed += self.previous_fire_speed
 134                     elif type == "relative":
 135                         # FIXME(jfw): Reference impl uses prvFireSpeed
 136                         # here?  That doesn't seem right at all.
 137                         speed += self.owner.speed
 138                 else:
 139                     speed = 1
 140                 self.previous_fire_speed = speed
 141
 142                 bullet = Bullet(self.owner.x, self.owner.y, direction, speed,
 143                                 self.owner.target, actions, self)
 144                 created.append(bullet)
 145
 146             elif isinstance(action, parser.ChangeSpeed):
 147                 frames, (speed, type) = action(self.params, self.rank)
 148                 self.speed_frames = frames
 149                 if type == "sequence":
 150                     self.speed = speed
 151                 elif type == "relative":
 152                     self.speed = speed / frames
 153                 else:
 154                     self.speed = (speed - self.owner.speed) / frames
 155
 156             elif isinstance(action, parser.ChangeDirection):
 157                 frames, (direction, type) = action(self.params, self.rank)
 158                 self.direction_frames = frames
 159                 self.aiming = False
 160                 if type == "sequence":
 161                     self.aiming = False
 162                     self.direction = direction
 163                 else:
 164                     if type == "absolute":
 165                         self.aiming = False
 166                         self.direction = (
 167                             direction - self.owner.direction) % 360
 168                     elif type == "relative":
 169                         self.aiming = False
 170                         self.direction = direction
 171                     else:
 172                         self.aiming = True
 173                         self.direction = (
 174                             direction
 175                             + self.owner.aim
 176                             - self.owner.direction) % 360
 177
 178                     while self.direction > 180:
 179                         self.direction -= 360
 180                     while self.direction < -180:
 181                         self.direction += 360
 182                     self.direction /= self.direction_frames
 183
 184             elif isinstance(action, parser.Accel):
 185                 frames, horizontal, vertical = action(self.params, self.rank)
 186                 self.accel_frames = frames
 187                 if horizontal:
 188                     mx, type = horizontal
 189                     if type == "sequence":
 190                         self.mx = mx
 191                     elif type == "absolute":
 192                         self.mx = (mx - bullet.mx) / frames
 193                     elif type == "relative":
 194                         self.mx = mx / frames
 195                 if vertical:
 196                     my, type = vertical
 197                     if type == "sequence":
 198                         self.my = my
 199                     elif type == "absolute":
 200                         self.my = (my - bullet.my) / frames
 201                     elif type == "relative":
 202                         self.my = my / frames
 203
 204             elif isinstance(action, parser.Wait):
 205                 self.wait_frames = action(self.params, self.rank)
 206                 break
 207
 208             elif isinstance(action, parser.Vanish):
 209                 self.owner.vanish()
 210                 break
 211
 212         return created
 213
 214 class Bullet(object):
 215     """Simple bullet implementation."""
 216
 217     def __init__(self, x=0, y=0, direction=0, speed=0, target=None,
 218                  actions=(), parent=None):
 219         self.x = self.px = x
 220         self.y = self.py = y
 221         self.mx = 0
 222         self.my = 0
 223         self.direction = direction
 224         self.speed = speed
 225         self.vanished = False
 226         self.target = target
 227         self.actions = []
 228         if actions and not parent:
 229             raise errors.Error
 230         for action, params in actions:
 231             self.actions.append(
 232                 Action(self, parent, action, params, parent.rank))
 233
 234     def __repr__(self):
 235         return ("%s(%r, %r, accel=%r, direction=%r, speed=%r, "
 236                 "actions=%r, target=%r, vanished=%r)") % (
 237             type(self).__name__, self.x, self.y, (self.mx, self.my),
 238             self.direction, self.speed, self.actions, self.target,
 239             self.vanished)
 240
 241     @property
 242     def aim(self):
 243         """Angle to the target."""
 244         if self.target is None:
 245             return self.direction
 246         else:
 247             return math.atan2(self.target.x - self.x, self.target.y - self.y)
 248
 249     def vanish(self):
 250         """Vanish this bullet and stop all actions."""
 251         self.vanished = True
 252         for action in self.actions:
 253             action.vanish()
 254         self.actions = []
 255
 256     def replace(self, old, new):
 257         try:
 258             idx = self.actions.index(old)
 259         except ValueError:
 260             pass
 261         else:
 262             self.actions[idx] = new
 263
 264     def step(self):
 265         created = []
 266
 267         for action in self.actions:
 268             created.extend(action.step())
 269
 270         direction = math.degrees(self.direction)
 271         self.x += self.mx + math.sin(direction) * self.speed
 272         self.y += self.my + math.cos(direction) * self.speed
 273
 274         return created