X-Git-Url: https://git.yukkurigames.com/?p=python-bulletml.git;a=blobdiff_plain;f=bulletml%2Fimpl.py;h=3326ceccc7a230a6d1d07d93bd7cae10c4e0ad3f;hp=af3f153906eed6c1f7180e37d622a0749ddc9d3d;hb=41f351faf847cb5bc88c7ff5fc6c21bafc9aa5ee;hpb=5f93dc227463ac9a34bfe4d06b67b7d07bfb12cc diff --git a/bulletml/impl.py b/bulletml/impl.py index af3f153..3326cec 100644 --- a/bulletml/impl.py +++ b/bulletml/impl.py @@ -14,22 +14,21 @@ from bulletml import parser PI_2 = math.pi * 2 +__all__ = ["Action", "Bullet"] + class Action(object): """Running action implementation.""" - def __init__(self, owner, parent, actions, params, rank): + def __init__(self, owner, parent, actions, params, rank, repeat=1): self.actions = actions self.parent = parent - self.repeat = 1 + self.repeat = repeat self.wait_frames = 0 self.speed = 0 self.speed_frames = 0 - self.aim_direction = 0 self.direction = 0 self.direction_frames = 0 self.aiming = False - self.aim_mx = 0 - self.aim_my = 0 self.mx = 0 self.my = 0 self.owner = owner @@ -76,10 +75,13 @@ class Action(object): self.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: + self.owner.direction += self.owner.aim else: self.owner.direction += self.direction @@ -98,7 +100,9 @@ class Action(object): while True: self.pc += 1 - if self.pc >= len(self.actions): + try: + action = self.actions[self.pc] + except IndexError: self.repeat -= 1 if self.repeat <= 0: self.pc = None @@ -109,13 +113,12 @@ class Action(object): break else: self.pc = 0 - - action = self.actions[self.pc] + 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) - child.repeat = repeat + child = Action( + self.owner, self, actions, params, self.rank, repeat) self.owner.replace(self, child) created.extend(child.step()) break @@ -141,14 +144,16 @@ class Action(object): direction = self.owner.aim self.previous_fire_direction = direction - if speed: speed, type = speed if type == "sequence": speed += self.previous_fire_speed elif type == "relative": - # FIXME(jfw): Reference impl uses prvFireSpeed - # here? That doesn't seem right at all. + # 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 else: speed = 1 @@ -173,15 +178,12 @@ class Action(object): self.direction_frames = frames self.aiming = False if type == "sequence": - self.aiming = False self.direction = direction else: if type == "absolute": - self.aiming = False self.direction = ( direction - self.owner.direction) % PI_2 elif type == "relative": - self.aiming = False self.direction = direction else: self.aiming = True @@ -190,9 +192,9 @@ class Action(object): + self.owner.aim - self.owner.direction) % PI_2 - while self.direction > math.pi: + if self.direction > math.pi: self.direction -= PI_2 - while self.direction < -math.pi: + if self.direction < -math.pi: self.direction += PI_2 self.direction /= self.direction_frames @@ -227,7 +229,24 @@ class Action(object): 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 action + + Contructor Arguments: + x, y, direction, speed, target - same as the attributes + actions - internal action list + parent - parent of actions, None for manually-created bullets + rank - game difficulty, 0 to 1 + + """ def __init__(self, x=0, y=0, direction=0, speed=0, target=None, actions=(), parent=None, rank=None): @@ -239,23 +258,22 @@ class Bullet(object): self.speed = speed self.vanished = False self.target = target - self.actions = [] if rank is None: rank = parent.rank if parent else 0.5 # New bullets reset the parent hierarchy. - self.actions = [Action(self, None, action, params, rank) - for action, params in actions] + self._actions = [Action(self, None, action, params, rank) + for action, params in actions] def __repr__(self): return ("%s(%r, %r, accel=%r, direction=%r, speed=%r, " "actions=%r, target=%r, vanished=%r)") % ( type(self).__name__, self.x, self.y, (self.mx, self.my), - self.direction, self.speed, self.actions, self.target, + self.direction, self.speed, self._actions, self.target, self.vanished) @property def aim(self): - """Angle to the target.""" + """Angle to the target, in radians.""" if self.target is None: return self.direction else: @@ -263,10 +281,18 @@ class Bullet(object): @property def finished(self): - """Check if this bullet is finished running.""" + """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). + """ if not self.vanished: return False - for action in self.actions: + for action in self._actions: if not action.finished: return False return True @@ -274,24 +300,33 @@ class Bullet(object): def vanish(self): """Vanish this bullet and stop all actions.""" self.vanished = True - for action in self.actions: + for action in self._actions: action.vanish() - self.actions = [] + 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) + idx = self._actions.index(old) except ValueError: pass else: - self.actions[idx] = new + self._actions[idx] = new def step(self): - """Advance by one frame.""" + """Advance by one frame. + + 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: + for action in self._actions: created.extend(action.step()) self.px = self.x @@ -300,11 +335,3 @@ class Bullet(object): 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) -