Major refactor. Since Python is duck-typed the parser/impl split in the Java BulletML...
authorJoe Wreschnig <joe.wreschnig@gmail.com>
Mon, 19 Apr 2010 08:15:59 +0000 (01:15 -0700)
committerJoe Wreschnig <joe.wreschnig@gmail.com>
Mon, 19 Apr 2010 08:15:59 +0000 (01:15 -0700)
bulletml/impl.py
bulletml/parser.py

index 262b7dc..ca800be 100644 (file)
@@ -2,33 +2,26 @@
 
 from __future__ import division
 
-from math import atan2, sin, cos, pi as PI
+from math import atan2, sin, cos
 
 from bulletml import parser
 
-PI_2 = PI * 2
-
 __all__ = ["Action", "Bullet"]
 
 class Action(object):
     """Running action implementation.
 
-    To implement new actions,
+    To implement new actions, add a new element/class pair to
+    parser.ActionDef.CONSTRUCTORS.  It should support FromXML,
+    __getstate__, and __setstate__, and 5-ary __call__:
 
-    - 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 __call__(self, owner, action, params, rank, created)
 
-    Or, for very simple actions, add it to the Action.CUSTOM
-    dictionary.  The key should be the type of the action and the
-    value a 3-ary callable that recieves the Action instance, the
-    owner, and a list to append created bullets to.
-    """
+    Which will be called to execute it. This function should modify
+    owner, action, and created in-place, and return true if action
+    execution should stop for this bullet this frame.
 
-    CUSTOM = {}
+    """
 
     def __init__(self, owner, parent, actions, params, rank, repeat=1):
         self.actions = actions
@@ -122,168 +115,16 @@ class Action(object):
                     self.pc = 0
                     action = self.actions[self.pc]
 
-            if isinstance(action, parser.Repeat):
-                repeat, (actions, params) = action(s_params, rank)
-                child = self.__class__(
-                    owner, self, actions, params, rank, repeat)
-                owner.replace(self, child)
-                child.step(owner, created)
-                break
-
-            elif isinstance(action, (parser.ActionDef, parser.ActionRef)):
+            if isinstance(action, (parser.ActionDef, parser.ActionRef)):
                 actions, params = action(s_params, rank)
                 child = self.__class__(owner, self, actions, params, rank)
                 owner.replace(self, child)
                 child.step(owner, created)
                 break
 
-            elif isinstance(action, (parser.FireDef, parser.FireRef)):
-                direction, speed, offset, tags, appearance, actions = action(
-                    s_params, rank)
-                if direction:
-                    direction, type = direction
-                    if type == "aim" or type is None:
-                        direction += owner.aim
-                    elif type == "sequence":
-                        direction += self.previous_fire_direction
-                    elif type == "relative":
-                        direction += owner.direction
-                else:
-                    direction = owner.aim
-                self.previous_fire_direction = direction
-
-                if speed:
-                    speed, type = speed
-                    if type == "sequence":
-                        speed += self.previous_fire_speed
-                    elif type == "relative":
-                        # The reference Noiz implementation uses
-                        # prvFireSpeed here, but the standard is
-                        # 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
-
-                x, y = owner.x, owner.y
-                if offset:
-                    off_x, off_y = offset(s_params, rank)
-                    if offset.type == "relative":
-                        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
-
-                if appearance is None:
-                    appearance = owner.appearance
-                bullet = owner.__class__(
-                    x=x, y=y, direction=direction, speed=speed,
-                    target=owner.target, actions=actions, rank=rank,
-                    appearance=appearance, tags=tags, Action=self.__class__)
-                created.append(bullet)
-
-            elif isinstance(action, parser.ChangeSpeed):
-                frames, (speed, type) = action(s_params, rank)
-                self.speed_frames = frames
-                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
-                else:
-                    self.speed = (speed - owner.speed) / frames
-
-            elif isinstance(action, parser.ChangeDirection):
-                frames, (direction, type) = action(s_params, rank)
-                self.direction_frames = frames
-                self.aiming = False
-                if type == "sequence":
-                    self.direction = direction
-                else:
-                    if type == "absolute":
-                        direction -= owner.direction
-                    elif type != "relative": # aim or default
-                        self.aiming = True
-                        direction += owner.aim - owner.direction
-
-                    # Normalize to [-pi, pi).
-                    direction = (direction + PI) % PI_2 - PI
-                    if frames <= 0:
-                        owner.direction += direction
-                    else:
-                        self.direction = direction / frames
-
-            elif isinstance(action, parser.Accel):
-                frames, horizontal, vertical = action(s_params, rank)
-                self.accel_frames = frames
-                if horizontal:
-                    mx, type = horizontal
-                    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
-                    elif type == "relative":
-                        self.mx = mx / frames
-                if vertical:
-                    my, type = vertical
-                    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(s_params, rank)
-                break
-
-            elif isinstance(action, parser.Vanish):
-                owner.vanish()
+            elif action(owner, self, s_params, rank, created):
                 break
 
-            elif isinstance(action, parser.Appearance):
-                owner.appearance = action.appearance
-
-            else:
-                self.handle(action, owner, created)
-
-    def handle(self, action, owner, created):
-        """Override in subclasses for new action types."""
-        try:
-            handler = self.CUSTOM[type(action)]
-        except KeyError:
-            raise NotImplementedError(action.__class__.__name__)
-        else:
-            handler(self, owner, created)
-
 class Bullet(object):
     """Simple bullet implementation.
 
@@ -305,7 +146,6 @@ class Bullet(object):
     actions - internal action list
     Action - custom Action constructor
 
-
     """
 
     def __init__(self, x=0, y=0, direction=0, speed=0, target=None,
index c4b3e04..653b90f 100644 (file)
@@ -3,13 +3,13 @@
 This is based on the format described at
 http://www.asahi-net.or.jp/~cs8k-cyu/bulletml/bulletml_ref_e.html.
 
-Unless you are adding support for new tags, the only class you should
-care about in here is BulletML.
+Unless you are adding support for new actions, the only class you
+should care about in here is BulletML.
 """
 
 from __future__ import division
 
-import math
+from math import sin, cos, radians, pi as PI
 
 from xml.etree.ElementTree import ElementTree
 
@@ -33,6 +33,8 @@ from bulletml.expr import NumberDef, INumberDef
 
 __all__ = ["ParseError", "BulletML"]
 
+PI_2 = PI * 2
+
 class ParseError(Error):
     """Raised when an error occurs parsing the XML structure."""
     pass
@@ -86,7 +88,7 @@ class Direction(object):
         return cls(element.get("type", default), NumberDef(element.text))
 
     def __call__(self, params, rank):
-        return (math.radians(self.value(params, rank)), self.type)
+        return (radians(self.value(params, rank)), self.type)
 
     def __repr__(self):
         return "%s(%r, type=%r)" % (
@@ -123,8 +125,26 @@ class ChangeDirection(object):
         except UnboundLocalError as exc:
             raise ParseError(str(exc))
 
-    def __call__(self, params, rank):
-        return self.term(params, rank), self.direction(params, rank)
+    def __call__(self, owner, action, params, rank, created):
+        frames = self.term(params, rank)
+        direction, type = self.direction(params, rank)
+        action.direction_frames = frames
+        action.aiming = False
+        if type == "sequence":
+            action.direction = direction
+        else:
+            if type == "absolute":
+                direction -= owner.direction
+            elif type != "relative": # aim or default
+                action.aiming = True
+                direction += owner.aim - owner.direction
+
+            # Normalize to [-pi, pi).
+            direction = (direction + PI) % PI_2 - PI
+            if frames <= 0:
+                owner.direction += direction
+            else:
+                action.direction = direction / frames
 
     def __repr__(self):
         return "%s(term=%r, direction=%r)" % (
@@ -190,8 +210,21 @@ class ChangeSpeed(object):
         except UnboundLocalError as exc:
             raise ParseError(str(exc))
 
-    def __call__(self, params, rank):
-        return self.term(params, rank), self.speed(params, rank)
+    def __call__(self, owner, action, params, rank, created):
+        frames = self.term(params, rank)
+        speed, type = self.speed(params, rank)
+        action.speed_frames = frames
+        if frames <= 0:
+            if type == "absolute":
+                owner.speed = speed
+            elif type == "relative":
+                owner.speed += speed
+        elif type == "sequence":
+            action.speed = speed
+        elif type == "relative":
+            action.speed = speed / frames
+        else:
+            action.speed = (speed - owner.speed) / frames
 
     def __repr__(self):
         return "%s(term=%r, speed=%r)" % (
@@ -214,8 +247,9 @@ class Wait(object):
         """Construct using an ElementTree-style element."""
         return cls(INumberDef(element.text))
 
-    def __call__(self, params, rank):
-        return self.frames(params, rank)
+    def __call__(self, owner, action, params, rank, created):
+        action.wait_frames = self.frames(params, rank)
+        return True
 
     def __repr__(self):
         return "%s(%r)" % (type(self).__name__, self.frames)
@@ -237,6 +271,9 @@ class Tag(object):
         """Construct using an ElementTree-style element."""
         return cls(element.text)
 
+    def __call__(self, owner, action, params, rank, created):
+        owner.tags.add(self.tag)
+
 class Untag(object):
     """Unset a bullet tag."""
 
@@ -254,6 +291,12 @@ class Untag(object):
         """Construct using an ElementTree-style element."""
         return cls(element.text)
 
+    def __call__(self, owner, action, params, rank, created):
+        try:
+            owner.tags.remove(self.tag)
+        except KeyError:
+            pass
+
 class Appearance(object):
     """Set a bullet appearance."""
 
@@ -271,6 +314,9 @@ class Appearance(object):
         """Construct using an ElementTree-style element."""
         return cls(element.text)
 
+    def __call__(self, owner, action, params, rank, created):
+        owner.apearance = self.appearance
+
 class Vanish(object):
     """Make the owner disappear."""
 
@@ -285,6 +331,10 @@ class Vanish(object):
     def __repr__(self):
         return "%s()" % (type(self).__name__)
 
+    def __call__(self, owner, action, params, rank, created):
+        owner.vanish()
+        return True
+
 class Repeat(object):
     """Repeat an action definition."""
 
@@ -315,8 +365,14 @@ class Repeat(object):
         except UnboundLocalError as exc:
             raise ParseError(str(exc))
 
-    def __call__(self, params, rank):
-        return self.times(params, rank), self.action(params, rank)
+    def __call__(self, owner, action, params, rank, created):
+        repeat = self.times(params, rank)
+        actions, params = self.action(params, rank)
+        child = action.__class__(
+            owner, action, actions, params, rank, repeat)
+        owner.replace(action, child)
+        child.step(owner, created)
+        return True
 
     def __repr__(self):
         return "%s(%r, %r)" % (type(self).__name__, self.times, self.action)
@@ -365,11 +421,37 @@ class Accel(object):
         except AttributeError:
             raise ParseError
 
-    def __call__(self, params, rank):
+    def __call__(self, owner, action, params, rank, created):
         frames = self.term(params, rank)
         horizontal = self.horizontal and self.horizontal(params, rank)
         vertical = self.vertical and self.vertical(params, rank)
-        return frames, horizontal, vertical
+        action.accel_frames = frames
+        if horizontal:
+            mx, type = horizontal
+            if frames <= 0:
+                if type == "absolute":
+                    owner.mx = mx
+                elif type == "relative":
+                    owner.mx += mx
+            elif type == "sequence":
+                action.mx = mx
+            elif type == "absolute":
+                action.mx = (mx - owner.mx) / frames
+            elif type == "relative":
+                action.mx = mx / frames
+        if vertical:
+            my, type = vertical
+            if frames <= 0:
+                if type == "absolute":
+                    owner.my = my
+                elif type == "relative":
+                    owner.my += my
+            elif type == "sequence":
+                action.my = my
+            elif type == "absolute":
+                action.my = (my - owner.my) / frames
+            elif type == "relative":
+                action.my = my / frames
 
     def __repr__(self):
         return "%s(%r, horizontal=%r, vertical=%r)" % (
@@ -671,7 +753,7 @@ class FireDef(object):
             doc._fires[element.get("label")] = fire
             return fire
 
-    def __call__(self, params, rank):
+    def __call__(self, owner, action, params, rank, created):
         direction, speed, tags, appearance, actions = self.bullet(params, rank)
         if self.direction:
             direction = self.direction(params, rank)
@@ -680,7 +762,53 @@ class FireDef(object):
         tags = tags.union(self.tags)
         if self.appearance:
             appearance = self.appearance
-        return direction, speed, self.offset, tags, appearance, actions
+
+        if direction:
+            direction, type = direction
+            if type == "aim" or type is None:
+                direction += owner.aim
+            elif type == "sequence":
+                direction += action.previous_fire_direction
+            elif type == "relative":
+                direction += owner.direction
+        else:
+            direction = owner.aim
+        action.previous_fire_direction = direction
+
+        if speed:
+            speed, type = speed
+            if type == "sequence":
+                speed += action.previous_fire_speed
+            elif type == "relative":
+                # The reference Noiz implementation uses
+                # prvFireSpeed here, but the standard is
+                # 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
+        action.previous_fire_speed = speed
+
+        x, y = owner.x, owner.y
+        if self.offset:
+            off_x, off_y = self.offset(params, rank)
+            if self.offset.type == "relative":
+                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
+
+        if appearance is None:
+            appearance = owner.appearance
+        bullet = owner.__class__(
+            x=x, y=y, direction=direction, speed=speed,
+            target=owner.target, actions=actions, rank=rank,
+            appearance=appearance, tags=tags, Action=action.__class__)
+        created.append(bullet)
 
     def __repr__(self):
         return "%s(direction=%r, speed=%r, bullet=%r)" % (
@@ -714,8 +842,9 @@ class FireRef(object):
         doc._fire_refs.append(fired)
         return fired
 
-    def __call__(self, params, rank):
-        return self.fire(self.params(params, rank), rank)
+    def __call__(self, owner, action, params, rank, created):
+        params = self.params(params, rank)
+        return self.fire(owner, action, params, rank, created)
 
     def __repr__(self):
         return "%s(params=%r, fire=%r)" % (