1 """BulletML implementation."""
3 from __future__
import division
7 from bulletml
import parser
11 __all__
= ["Action", "Bullet"]
14 """Running action implementation.
16 To implement new actions,
18 - Add a new element/class pair to parser.ActionDef.CONSTRUCTORS.
19 It should support FromXML, __getstate__, and __setstate__.
20 - Subclass impl.Action and override the 'handle' method to handle
21 your custom action type.
22 - Pass the impl.Bullet constructor your Action subclass when
23 creating your root Bullet.
26 def __init__(self
, owner
, parent
, actions
, params
, rank
, repeat
=1):
27 self
.actions
= actions
34 self
.direction_frames
= 0
39 self
.previous_fire_direction
= 0
40 self
.previous_fire_speed
= 0
45 self
.copy_state(parent
)
48 return "%s(pc=%r, actions=%r)" % (
49 type(self
).__name
__, self
.pc
, self
.actions
)
52 """End this action and its parents."""
58 def copy_state(self
, other
):
59 """Copy fire/movement state from other to self."""
60 self
.direction_frames
= other
.direction_frames
61 self
.direction
= other
.direction
62 self
.aiming
= other
.aiming
63 self
.speed_frames
= other
.speed_frames
64 self
.speed
= other
.speed
65 self
.accel_frames
= other
.accel_frames
68 self
.previous_fire_direction
= other
.previous_fire_direction
69 self
.previous_fire_speed
= other
.previous_fire_speed
71 def step(self
, owner
, created
, sin
=math
.sin
, cos
=math
.cos
):
72 """Advance by one frame."""
73 s_params
= self
.params
76 if self
.speed_frames
> 0:
77 self
.speed_frames
-= 1
78 owner
.speed
+= self
.speed
80 if self
.direction_frames
> 0:
81 # The Noiz implementation was a little weird here, I think
82 # there was a bug in it that prevented it from working if
83 # the frame count was 1. I'm still not sure what the aim
84 # check is supposed to do, exactly.
85 self
.direction_frames
-= 1
86 if self
.aiming
and self
.direction_frames
<= 0:
87 owner
.direction
+= owner
.aim
89 owner
.direction
+= self
.direction
91 if self
.accel_frames
> 0:
92 self
.accel_frames
-= 1
99 if self
.wait_frames
> 0:
100 self
.wait_frames
-= 1
107 action
= self
.actions
[self
.pc
]
113 if self
.parent
is not None:
114 self
.parent
.copy_state(self
)
115 owner
.replace(self
, self
.parent
)
119 action
= self
.actions
[self
.pc
]
121 if isinstance(action
, parser
.Repeat
):
122 repeat
, (actions
, params
) = action(s_params
, rank
)
123 child
= self
.__class
__(
124 owner
, self
, actions
, params
, rank
, repeat
)
125 owner
.replace(self
, child
)
126 child
.step(owner
, created
, sin
, cos
)
129 elif isinstance(action
, (parser
.ActionDef
, parser
.ActionRef
)):
130 actions
, params
= action(s_params
, rank
)
131 child
= self
.__class
__(owner
, self
, actions
, params
, rank
)
132 owner
.replace(self
, child
)
133 child
.step(owner
, created
, sin
, cos
)
136 elif isinstance(action
, (parser
.FireDef
, parser
.FireRef
)):
137 direction
, speed
, actions
, offset
= action(s_params
, rank
)
139 direction
, type = direction
140 if type == "aim" or type is None:
141 direction
+= owner
.aim
142 elif type == "sequence":
143 direction
+= self
.previous_fire_direction
144 elif type == "relative":
145 direction
+= owner
.direction
147 direction
= owner
.aim
148 self
.previous_fire_direction
= direction
152 if type == "sequence":
153 speed
+= self
.previous_fire_speed
154 elif type == "relative":
155 # The reference Noiz implementation uses
156 # prvFireSpeed here, but the standard is
157 # pretty clear -- "In case of the type is
158 # "relative", ... the speed is relative to the
159 # speed of this bullet."
163 self
.previous_fire_speed
= speed
165 x
, y
= owner
.x
, owner
.y
167 off_x
, off_y
= offset(s_params
, rank
)
168 if offset
.type == "relative":
171 x
+= c
* off_x
+ s
* off_y
172 y
+= s
* off_x
- c
* off_y
177 bullet
= owner
.__class
__(
178 x
, y
, direction
, speed
, owner
.target
, actions
, rank
)
179 created
.append(bullet
)
181 elif isinstance(action
, parser
.ChangeSpeed
):
182 frames
, (speed
, type) = action(s_params
, rank
)
183 self
.speed_frames
= frames
185 if type == "absolute":
187 elif type == "relative":
189 elif type == "sequence":
191 elif type == "relative":
192 self
.speed
= speed
/ frames
194 self
.speed
= (speed
- owner
.speed
) / frames
196 elif isinstance(action
, parser
.ChangeDirection
):
197 frames
, (direction
, type) = action(s_params
, rank
)
198 self
.direction_frames
= frames
200 if type == "sequence":
201 self
.direction
= direction
203 if type == "absolute":
204 direction
-= owner
.direction
205 elif type != "relative": # aim or default
207 direction
+= owner
.aim
- owner
.direction
209 # Normalize to [-pi, pi).
210 direction
= (direction
+ math
.pi
) % PI_2
- math
.pi
212 owner
.direction
+= direction
214 self
.direction
= direction
/ frames
216 elif isinstance(action
, parser
.Accel
):
217 frames
, horizontal
, vertical
= action(s_params
, rank
)
218 self
.accel_frames
= frames
220 mx
, type = horizontal
222 if type == "absolute":
224 elif type == "relative":
226 elif type == "sequence":
228 elif type == "absolute":
229 self
.mx
= (mx
- owner
.mx
) / frames
230 elif type == "relative":
231 self
.mx
= mx
/ frames
235 if type == "absolute":
237 elif type == "relative":
239 elif type == "sequence":
241 elif type == "absolute":
242 self
.my
= (my
- owner
.my
) / frames
243 elif type == "relative":
244 self
.my
= my
/ frames
246 elif isinstance(action
, parser
.Tag
):
247 owner
.tags
.add(action
.tag
)
249 elif isinstance(action
, parser
.Untag
):
251 owner
.tags
.remove(action
.tag
)
255 elif isinstance(action
, parser
.Wait
):
256 self
.wait_frames
= action(s_params
, rank
)
259 elif isinstance(action
, parser
.Vanish
):
264 self
.handle(action
, owner
, created
, sin
, cos
)
266 def handle(self
, action
, owner
, created
, sin
, cos
):
267 """Override in subclasses for new action types."""
268 raise NotImplementedError(action
.__class
__.__name
__)
270 class Bullet(object):
271 """Simple bullet implementation.
274 x, y - current X/Y position
275 px, py - X/Y position prior to the last step
276 mx, my - X/Y axis-oriented speed modifier ("acceleration")
277 direction - direction of movement, in radians
278 speed - speed of movement, in units per frame
279 target - object with .x and .y fields for "aim" directions
280 vanished - set to true by a <vanish> action
281 rank - game difficulty, 0 to 1, default 0.5
282 tags - string tags set by the running actions
284 Contructor Arguments:
285 x, y, direction, speed, target, rank - same as the attributes
286 actions - internal action list
287 parent - parent of actions, None for manually-created bullets
292 def __init__(self
, x
=0, y
=0, direction
=0, speed
=0, target
=None,
293 actions
=(), rank
=0.5, Action
=Action
):
298 self
.direction
= direction
300 self
.vanished
= False
304 # New bullets reset the parent hierarchy.
305 self
._actions
= [Action(self
, None, action
, params
, rank
)
306 for action
, params
in actions
]
309 def FromDocument(cls
, doc
, x
=0, y
=0, direction
=0, speed
=0, target
=None,
310 params
=(), rank
=0.5, Action
=Action
):
311 """Construct a new Bullet from a loaded BulletML document."""
312 actions
= [a(params
, rank
) for a
in doc
.actions
]
313 return cls(x
, y
, direction
, speed
, target
, actions
, rank
, Action
)
316 return ("%s(%r, %r, accel=%r, direction=%r, speed=%r, "
317 "actions=%r, target=%r, vanished=%r)") % (
318 type(self
).__name
__, self
.x
, self
.y
, (self
.mx
, self
.my
),
319 self
.direction
, self
.speed
, self
._actions
, self
.target
,
324 """Angle to the target, in radians.
326 If the target does not exist or cannot be found, return 0.
329 target_x
= self
.target
.x
330 target_y
= self
.target
.y
331 except AttributeError:
334 return math
.atan2(target_x
- self
.x
, self
.y
- target_y
)
338 """Check if this bullet is finished running.
340 A bullet is finished when it has vanished, and all its
341 actions have finished.
343 If this is true, the bullet should be removed from the screen.
344 (You will probably want to cull it under other circumstances
347 if not self
.vanished
:
349 for action
in self
._actions
:
350 if not action
.finished
:
355 """Vanish this bullet and stop all actions."""
357 for action
in self
._actions
:
361 def replace(self
, old
, new
):
362 """Replace an active action with another.
364 This is mostly used by actions internally to queue children.
367 idx
= self
._actions
.index(old
)
371 self
._actions
[idx
] = new
373 def step(self
, sin
=math
.sin
, cos
=math
.cos
):
374 """Advance by one frame.
376 This updates the position and velocity, and may also set the
379 It returns any new bullets this bullet spawned during this step.
383 for action
in self
._actions
:
384 action
.step(self
, created
, sin
, cos
)
388 self
.x
+= self
.mx
+ sin(self
.direction
) * self
.speed
389 self
.y
+= self
.my
- cos(self
.direction
) * self
.speed