Separate element constructors from regular constructors.

[python-bulletml.git] / bulletml / impl.py

diff --git a/bulletml/impl.py b/bulletml/impl.py
index c228a33..92982db 100644 (file)
--- a/bulletml/impl.py
+++ b/bulletml/impl.py
@@ -7,7 +7,7 @@ from __future__ import division
 
 import math
 
-from bulletml import parser, errors
+from bulletml import parser
 
 # TODO(jfw): This is very non-Pythonic, it's pretty much just the
 # BulletML reference ActionImpl translated to Python.
@@ -18,7 +18,7 @@ class Action(object):
     def __init__(self, owner, parent, actions, params, rank):
         self.actions = actions
         self.parent = parent
-        self.repeat = 0
+        self.repeat = 1
         self.wait_frames = 0
         self.speed = 0
         self.speed_frames = 0
@@ -40,10 +40,17 @@ class Action(object):
         if parent:
             self.copy_state(parent)
 
+    def __repr__(self):
+        return "%s(pc=%r, actions=%r)" % (
+            type(self).__name__, self.pc, self.actions)
+
+    @property
+    def finished(self):
+        return self.pc is None
+
     def vanish(self):
         if self.parent:
             self.parent.vanish()
-        self.repeat = 0
         self.pc = None
 
     def copy_state(self, other):
@@ -64,6 +71,7 @@ class Action(object):
         if self.speed_frames > 0:
             self.speed_frames -= 1
             self.owner.speed += self.speed
+
         if self.direction_frames > 0:
             self.direction_frames -= 1
             if self.direction_frames <= 0:
@@ -71,6 +79,7 @@ class Action(object):
                     self.owner.direction += self.owner.aim
             else:
                 self.owner.direction += self.direction
+
         if self.accel_frames > 0:
             self.accel_frames -= 1
             self.owner.mx += self.mx
@@ -85,9 +94,11 @@ class Action(object):
 
         while True:
             self.pc += 1
+
             if self.pc >= len(self.actions):
                 self.repeat -= 1
                 if self.repeat <= 0:
+                    self.pc = None
                     if self.parent is not None:
                         self.parent.copy_state(self)
                         self.owner.replace(self, self.parent)
@@ -106,7 +117,7 @@ class Action(object):
                 break
 
             elif isinstance(action, (parser.ActionDef, parser.ActionRef)):
-                action, params = action(self.params, self.rank)
+                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())
@@ -116,7 +127,7 @@ class Action(object):
                 direction, speed, actions = action(self.params, self.rank)
                 if direction:
                     direction, type = direction
-                    if type == "aim":
+                    if type == "aim" or type is None:
                         direction += self.owner.aim
                     elif type == "sequence":
                         direction += self.previous_fire_direction
@@ -189,7 +200,7 @@ class Action(object):
                     if type == "sequence":
                         self.mx = mx
                     elif type == "absolute":
-                        self.mx = (mx - bullet.mx) / frames
+                        self.mx = (mx - self.owner.mx) / frames
                     elif type == "relative":
                         self.mx = mx / frames
                 if vertical:
@@ -197,7 +208,7 @@ class Action(object):
                     if type == "sequence":
                         self.my = my
                     elif type == "absolute":
-                        self.my = (my - bullet.my) / frames
+                        self.my = (my - self.owner.my) / frames
                     elif type == "relative":
                         self.my = my / frames
 
@@ -215,7 +226,7 @@ class Bullet(object):
     """Simple bullet implementation."""
 
     def __init__(self, x=0, y=0, direction=0, speed=0, target=None,
-                 actions=(), parent=None):
+                 actions=(), parent=None, rank=None):
         self.x = self.px = x
         self.y = self.py = y
         self.mx = 0
@@ -225,11 +236,11 @@ class Bullet(object):
         self.vanished = False
         self.target = target
         self.actions = []
-        if actions and not parent:
-            raise errors.Error
-        for action, params in actions:
-            self.actions.append(
-                Action(self, parent, action, params, parent.rank))
+        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]
 
     def __repr__(self):
         return ("%s(%r, %r, accel=%r, direction=%r, speed=%r, "
@@ -244,7 +255,15 @@ class Bullet(object):
         if self.target is None:
             return self.direction
         else:
-            return math.atan2(self.target.x - self.x, self.target.y - self.y)
+            return math.degrees(
+                math.atan2(self.target.x - self.x, self.y - self.target.y))
+
+    @property
+    def finished(self):
+        for action in self.actions:
+            if not action.finished:
+                return False
+        return self.vanished
 
     def vanish(self):
         """Vanish this bullet and stop all actions."""
@@ -267,8 +286,18 @@ class Bullet(object):
         for action in self.actions:
             created.extend(action.step())
 
-        direction = math.degrees(self.direction)
+        direction = math.radians(self.direction)
+        self.px = self.x
+        self.py = self.y
         self.x += self.mx + math.sin(direction) * self.speed
-        self.y += self.my + math.cos(direction) * self.speed
+        self.y += self.my - math.cos(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)
+