X-Git-Url: https://git.yukkurigames.com/?p=python-bulletml.git;a=blobdiff_plain;f=bulletml%2Fimpl.py;h=938e9e23ad85567a7a38c5a55d385af6cf5ba70f;hp=26b95804230b9f76877f5d41bfdf5ed841b1443f;hb=5da55ac7eeae21ee0ca3149bed99c95383397f05;hpb=16023be19df43f8b8acc4671e0fabdeffb0e720a

diff --git a/bulletml/impl.py b/bulletml/impl.py
index 26b9580..938e9e2 100644
--- a/bulletml/impl.py
+++ b/bulletml/impl.py
@@ -6,15 +6,22 @@ import math
 
 from bulletml import parser
 
-# TODO(jfw): This is very non-Pythonic, it's pretty much just the
-# BulletML reference ActionImpl translated to Python.
-
 PI_2 = math.pi * 2
 
 __all__ = ["Action", "Bullet"]
 
 class Action(object):
-    """Running action implementation."""
+    """Running action implementation.
+
+    To implement new actions,
+
+    - Add a new element/class pair to parser.ActionDef.CONSTRUCTORS.
+      It should support FromXML, __getstate__, and __setstate__.
+    - Subclass impl.Action and override the 'handle' method to handle
+      your custom action type.
+    - Pass the impl.Bullet constructor your Action subclass when
+      creating your root Bullet.
+    """
 
     def __init__(self, owner, parent, actions, params, rank, repeat=1):
         self.actions = actions
@@ -61,9 +68,10 @@ class Action(object):
         self.previous_fire_direction = other.previous_fire_direction
         self.previous_fire_speed = other.previous_fire_speed
 
-    def step(self, owner, rank):
+    def step(self, owner, created, sin=math.sin, cos=math.cos):
         """Advance by one frame."""
-        created = []
+        s_params = self.params
+        rank = owner.rank
 
         if self.speed_frames > 0:
             self.speed_frames -= 1
@@ -86,11 +94,11 @@ class Action(object):
             owner.my += self.my
 
         if self.pc is None:
-            return created
+            return
 
         if self.wait_frames > 0:
             self.wait_frames -= 1
-            return created
+            return
 
         while True:
             self.pc += 1
@@ -111,21 +119,22 @@ class Action(object):
                     action = self.actions[self.pc]
 
             if isinstance(action, parser.Repeat):
-                repeat, (actions, params) = action(self.params, rank)
-                child = Action(owner, self, actions, params, rank, repeat)
+                repeat, (actions, params) = action(s_params, rank)
+                child = self.__class__(
+                    owner, self, actions, params, rank, repeat)
                 owner.replace(self, child)
-                created.extend(child.step(owner, rank))
+                child.step(owner, created, sin, cos)
                 break
 
             elif isinstance(action, (parser.ActionDef, parser.ActionRef)):
-                actions, params = action(self.params, rank)
-                child = Action(owner, self, actions, params, rank)
+                actions, params = action(s_params, rank)
+                child = self.__class__(owner, self, actions, params, rank)
                 owner.replace(self, child)
-                created.extend(child.step(owner, rank))
+                child.step(owner, created, sin, cos)
                 break
 
             elif isinstance(action, (parser.FireDef, parser.FireRef)):
-                direction, speed, actions, offset = action(self.params, rank)
+                direction, speed, actions, offset = action(s_params, rank)
                 if direction:
                     direction, type = direction
                     if type == "aim" or type is None:
@@ -145,9 +154,9 @@ class Action(object):
                     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".
+                        # 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
@@ -155,24 +164,29 @@ class Action(object):
 
                 x, y = owner.x, owner.y
                 if offset:
-                    off_x, off_y = offset(self.params, rank)
+                    off_x, off_y = offset(s_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
+                        s = sin(direction)
+                        c = cos(direction)
+                        x += c * off_x + s * off_y
+                        y += s * off_x - c * off_y
                     else:
                         x += off_x
                         y += off_y
 
-                bullet = Bullet(
-                    x, y, direction, speed, owner.target, actions, self, rank)
+                bullet = owner.__class__(
+                    x, y, direction, speed, owner.target, actions, rank)
                 created.append(bullet)
 
             elif isinstance(action, parser.ChangeSpeed):
-                frames, (speed, type) = action(self.params, rank)
+                frames, (speed, type) = action(s_params, rank)
                 self.speed_frames = frames
-                if type == "sequence":
+                if frames <= 0:
+                    if type == "absolute":
+                        owner.speed = speed
+                    elif type == "relative":
+                        owner.speed += speed
+                elif type == "sequence":
                     self.speed = speed
                 elif type == "relative":
                     self.speed = speed / frames
@@ -180,36 +194,36 @@ class Action(object):
                     self.speed = (speed - owner.speed) / frames
 
             elif isinstance(action, parser.ChangeDirection):
-                frames, (direction, type) = action(self.params, rank)
+                frames, (direction, type) = action(s_params, rank)
                 self.direction_frames = frames
                 self.aiming = False
                 if type == "sequence":
                     self.direction = direction
                 else:
                     if type == "absolute":
-                        self.direction = (
-                            direction - owner.direction) % PI_2
-                    elif type == "relative":
-                        self.direction = direction
-                    else:
+                        direction -= owner.direction
+                    elif type != "relative": # aim or default
                         self.aiming = True
-                        self.direction = (
-                            direction
-                            + owner.aim
-                            - owner.direction) % PI_2
+                        direction += owner.aim - owner.direction
 
-                    if self.direction > math.pi:
-                        self.direction -= PI_2
-                    if self.direction < -math.pi:
-                        self.direction += PI_2
-                    self.direction /= self.direction_frames
+                    # Normalize to [-pi, pi).
+                    direction = (direction + math.pi) % PI_2 - math.pi
+                    if frames <= 0:
+                        owner.direction += direction
+                    else:
+                        self.direction = direction / frames
 
             elif isinstance(action, parser.Accel):
-                frames, horizontal, vertical = action(self.params, rank)
+                frames, horizontal, vertical = action(s_params, rank)
                 self.accel_frames = frames
                 if horizontal:
                     mx, type = horizontal
-                    if type == "sequence":
+                    if frames <= 0:
+                        if type == "absolute":
+                            owner.mx = mx
+                        elif type == "relative":
+                            owner.mx += mx
+                    elif type == "sequence":
                         self.mx = mx
                     elif type == "absolute":
                         self.mx = (mx - owner.mx) / frames
@@ -217,22 +231,41 @@ class Action(object):
                         self.mx = mx / frames
                 if vertical:
                     my, type = vertical
-                    if type == "sequence":
+                    if frames <= 0:
+                        if type == "absolute":
+                            owner.my = my
+                        elif type == "relative":
+                            owner.my += my
+                    elif type == "sequence":
                         self.my = my
                     elif type == "absolute":
                         self.my = (my - owner.my) / frames
                     elif type == "relative":
                         self.my = my / frames
 
+            elif isinstance(action, parser.Tag):
+                owner.tags.add(action.tag)
+
+            elif isinstance(action, parser.Untag):
+                try:
+                    owner.tags.remove(action.tag)
+                except KeyError:
+                    pass
+
             elif isinstance(action, parser.Wait):
-                self.wait_frames = action(self.params, rank)
+                self.wait_frames = action(s_params, rank)
                 break
 
             elif isinstance(action, parser.Vanish):
                 owner.vanish()
                 break
 
-        return created
+            else:
+                self.handle(action, owner, created, sin, cos)
+
+    def handle(self, action, owner, created, sin, cos):
+        """Override in subclasses for new action types."""
+        raise NotImplementedError(action.__class__.__name__)
 
 class Bullet(object):
     """Simple bullet implementation.
@@ -246,6 +279,7 @@ class Bullet(object):
     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
+    tags - string tags set by the running actions
 
     Contructor Arguments:
     x, y, direction, speed, target, rank - same as the attributes
@@ -256,7 +290,7 @@ class Bullet(object):
     """
 
     def __init__(self, x=0, y=0, direction=0, speed=0, target=None,
-                 actions=(), parent=None, rank=0.5):
+                 actions=(), rank=0.5, Action=Action):
         self.x = self.px = x
         self.y = self.py = y
         self.mx = 0
@@ -266,6 +300,7 @@ class Bullet(object):
         self.vanished = False
         self.target = target
         self.rank = rank
+        self.tags = set()
         # New bullets reset the parent hierarchy.
         self._actions = [Action(self, None, action, params, rank)
                          for action, params in actions]
@@ -322,7 +357,7 @@ class Bullet(object):
         else:
             self._actions[idx] = new
 
-    def step(self):
+    def step(self, sin=math.sin, cos=math.cos):
         """Advance by one frame.
 
         This updates the position and velocity, and may also set the
@@ -333,11 +368,11 @@ class Bullet(object):
         created = []
 
         for action in self._actions:
-            created.extend(action.step(self, self.rank))
+            action.step(self, created, sin, cos)
 
         self.px = self.x
         self.py = self.y
-        self.x += self.mx + math.sin(self.direction) * self.speed
-        self.y += self.my - math.cos(self.direction) * self.speed
+        self.x += self.mx + sin(self.direction) * self.speed
+        self.y += self.my - cos(self.direction) * self.speed
 
         return created