-"""BulletML implementation.
-
-http://www.asahi-net.or.jp/~cs8k-cyu/bulletml/index_e.html
-"""
+"""BulletML implementation."""
from __future__ import division
PI_2 = math.pi * 2
+__all__ = ["Action", "Bullet"]
+
class Action(object):
"""Running action implementation."""
self.aiming = False
self.mx = 0
self.my = 0
- self.owner = owner
self.accel_frames = 0
self.previous_fire_direction = 0
self.previous_fire_speed = 0
self.params = params
- self.rank = rank
self.pc = -1
self.finished = False
if parent:
self.previous_fire_direction = other.previous_fire_direction
self.previous_fire_speed = other.previous_fire_speed
- def step(self):
+ def step(self, owner, rank):
"""Advance by one frame."""
created = []
if self.speed_frames > 0:
self.speed_frames -= 1
- self.owner.speed += self.speed
+ owner.speed += self.speed
if self.direction_frames > 0:
+ # The Noiz implementation was a little weird here, I think
+ # there was a bug in it that prevented it from working if
+ # the frame count was 1. I'm still not sure what the aim
+ # check is supposed to do, exactly.
self.direction_frames -= 1
- if self.direction_frames <= 0:
- if self.aiming:
- self.owner.direction += self.owner.aim
+ if self.aiming and self.direction_frames <= 0:
+ owner.direction += owner.aim
else:
- self.owner.direction += self.direction
+ owner.direction += self.direction
if self.accel_frames > 0:
self.accel_frames -= 1
- self.owner.mx += self.mx
- self.owner.my += self.my
+ owner.mx += self.mx
+ owner.my += self.my
if self.pc is None:
return created
self.finished = True
if self.parent is not None:
self.parent.copy_state(self)
- self.owner.replace(self, self.parent)
+ owner.replace(self, self.parent)
break
else:
self.pc = 0
action = self.actions[self.pc]
if isinstance(action, parser.Repeat):
- repeat, (actions, params) = action(self.params, self.rank)
- child = Action(
- self.owner, self, actions, params, self.rank, repeat)
- self.owner.replace(self, child)
- created.extend(child.step())
+ repeat, (actions, params) = action(self.params, rank)
+ child = Action(owner, self, actions, params, rank, repeat)
+ owner.replace(self, child)
+ created.extend(child.step(owner, rank))
break
elif isinstance(action, (parser.ActionDef, parser.ActionRef)):
- actions, params = action(self.params, self.rank)
- child = Action(self.owner, self, actions, params, self.rank)
- self.owner.replace(self, child)
- created.extend(child.step())
+ actions, params = action(self.params, rank)
+ child = Action(owner, self, actions, params, rank)
+ owner.replace(self, child)
+ created.extend(child.step(owner, rank))
break
elif isinstance(action, (parser.FireDef, parser.FireRef)):
- direction, speed, actions = action(self.params, self.rank)
+ direction, speed, actions, offset = action(self.params, rank)
if direction:
direction, type = direction
if type == "aim" or type is None:
- direction += self.owner.aim
+ direction += owner.aim
elif type == "sequence":
direction += self.previous_fire_direction
elif type == "relative":
- direction += self.owner.direction
+ direction += owner.direction
else:
- direction = self.owner.aim
+ direction = owner.aim
self.previous_fire_direction = direction
if speed:
elif type == "relative":
# The reference Noiz implementation uses
# prvFireSpeed here, but the standard is
- # pretty clear -- "0 means that the direction
- # of this fire and the direction of the bullet
- # are the same".
- speed += self.owner.speed
+ # pretty clear -- "In case of the type is
+ # "relative", ... the speed is relative to the
+ # speed of this bullet."
+ speed += owner.speed
else:
speed = 1
self.previous_fire_speed = speed
- bullet = Bullet(self.owner.x, self.owner.y, direction, speed,
- self.owner.target, actions, self)
+ x, y = owner.x, owner.y
+ if offset:
+ off_x, off_y = offset(self.params, rank)
+ if offset.type == "relative":
+ sin = math.sin(direction)
+ cos = math.cos(direction)
+ x += cos * off_x + sin * off_y
+ y += sin * off_x - cos * off_y
+ else:
+ x += off_x
+ y += off_y
+
+ bullet = Bullet(
+ x, y, direction, speed, owner.target, actions, self, rank)
created.append(bullet)
elif isinstance(action, parser.ChangeSpeed):
- frames, (speed, type) = action(self.params, self.rank)
+ frames, (speed, type) = action(self.params, rank)
self.speed_frames = frames
if type == "sequence":
self.speed = speed
elif type == "relative":
self.speed = speed / frames
else:
- self.speed = (speed - self.owner.speed) / frames
+ self.speed = (speed - owner.speed) / frames
elif isinstance(action, parser.ChangeDirection):
- frames, (direction, type) = action(self.params, self.rank)
+ frames, (direction, type) = action(self.params, rank)
self.direction_frames = frames
self.aiming = False
if type == "sequence":
else:
if type == "absolute":
self.direction = (
- direction - self.owner.direction) % PI_2
+ direction - owner.direction) % PI_2
elif type == "relative":
self.direction = direction
else:
self.aiming = True
self.direction = (
direction
- + self.owner.aim
- - self.owner.direction) % PI_2
+ + owner.aim
+ - owner.direction) % PI_2
if self.direction > math.pi:
self.direction -= PI_2
self.direction /= self.direction_frames
elif isinstance(action, parser.Accel):
- frames, horizontal, vertical = action(self.params, self.rank)
+ frames, horizontal, vertical = action(self.params, rank)
self.accel_frames = frames
if horizontal:
mx, type = horizontal
if type == "sequence":
self.mx = mx
elif type == "absolute":
- self.mx = (mx - self.owner.mx) / frames
+ self.mx = (mx - owner.mx) / frames
elif type == "relative":
self.mx = mx / frames
if vertical:
if type == "sequence":
self.my = my
elif type == "absolute":
- self.my = (my - self.owner.my) / frames
+ self.my = (my - owner.my) / frames
elif type == "relative":
self.my = my / frames
elif isinstance(action, parser.Wait):
- self.wait_frames = action(self.params, self.rank)
+ self.wait_frames = action(self.params, rank)
break
elif isinstance(action, parser.Vanish):
- self.owner.vanish()
+ owner.vanish()
break
return created
class Bullet(object):
- """Simple bullet implementation."""
+ """Simple bullet implementation.
+
+ Attributes:
+ x, y - current X/Y position
+ px, py - X/Y position prior to the last step
+ mx, my - X/Y axis-oriented speed modifier ("acceleration")
+ direction - direction of movement, in radians
+ speed - speed of movement, in units per frame
+ target - object with .x and .y fields for "aim" directions
+ vanished - set to true by a <vanish> action
+ rank - game difficulty, 0 to 1, default 0.5
+
+ Contructor Arguments:
+ x, y, direction, speed, target, rank - same as the attributes
+ actions - internal action list
+ parent - parent of actions, None for manually-created bullets
+
+
+ """
def __init__(self, x=0, y=0, direction=0, speed=0, target=None,
- actions=(), parent=None, rank=None):
+ actions=(), parent=None, rank=0.5):
self.x = self.px = x
self.y = self.py = y
self.mx = 0
self.speed = speed
self.vanished = False
self.target = target
- if rank is None:
- rank = parent.rank if parent else 0.5
+ self.rank = rank
# New bullets reset the parent hierarchy.
self._actions = [Action(self, None, action, params, rank)
for action, params in actions]
@property
def aim(self):
- """Angle to the target."""
+ """Angle to the target, in radians."""
if self.target is None:
return self.direction
else:
def finished(self):
"""Check if this bullet is finished running.
+ A bullet is finished when it has vanished, and all its
+ actions have finished.
+
If this is true, the bullet should be removed from the screen.
(You will probably want to cull it under other circumstances
as well).
self._actions = []
def replace(self, old, new):
- """Replace an active action with another."""
+ """Replace an active action with another.
+
+ This is mostly used by actions internally to queue children.
+ """
try:
idx = self._actions.index(old)
except ValueError:
def step(self):
"""Advance by one frame.
- This updates the direction, speed, x, y, px, and py members,
- and may set the vanished flag.
+ This updates the position and velocity, and may also set the
+ vanished flag.
+
+ It returns any new bullets this bullet spawned during this step.
"""
created = []
for action in self._actions:
- created.extend(action.step())
+ created.extend(action.step(self, self.rank))
self.px = self.x
self.py = self.y
self.y += self.my - math.cos(self.direction) * self.speed
return created
-
- @classmethod
- def FromDoc(cls, doc, params=(), x=0, y=0, speed=0, direction=0,
- target=None, rank=0.5):
- """Construct a bullet from top-level actions in a document."""
- actions = [act(params, rank) for act in doc.top]
- return cls(x, y, direction, speed, target, actions, rank=rank)
projects / python-bulletml.git / blobdiff