defer importing ParticleSystemManager etc. until base.enableParticles() is called

direct/src/particles/Particles.py

@@ -1,6 +1,4 @@
 from pandac.PandaModules import *
-from direct.particles.ParticleManagerGlobal import *
-from direct.showbase.PhysicsManagerGlobal import *
 
 from pandac.PandaModules import ParticleSystem
 from pandac.PandaModules import BaseParticleFactory
@@ -83,14 +81,14 @@ class Particles(ParticleSystem):
 
     def enable(self):
         if (self.fEnabled == 0):
-            physicsMgr.attachPhysical(self)
+            base.physicsMgr.attachPhysical(self)
-            particleMgr.attachParticlesystem(self)
+            base.particleMgr.attachParticlesystem(self)
             self.fEnabled = 1
 
     def disable(self):
         if (self.fEnabled == 1):
-            physicsMgr.removePhysical(self)
+            base.physicsMgr.removePhysical(self)
-            particleMgr.removeParticlesystem(self)
+            base.particleMgr.removeParticlesystem(self)
             self.fEnabled = 0
 
     def isEnabled(self):

direct/src/showbase/ShowBase.py

@@ -21,8 +21,6 @@ from JobManagerGlobal import *
 from EventManagerGlobal import *
 from PythonUtil import *
 from direct.showbase import PythonUtil
-from direct.particles.ParticleManagerGlobal import *
-from PhysicsManagerGlobal import *
 #from direct.interval.IntervalManager import ivalMgr
 from direct.interval import IntervalManager
 from InputStateGlobal import inputState
@@ -243,14 +241,11 @@ class ShowBase(DirectObject.DirectObject):
         self.jobMgr = jobMgr
 
         # Particle manager
-        self.particleMgr = particleMgr
+        self.particleMgr = None
-        self.particleMgr.setFrameStepping(1)
         self.particleMgrEnabled = 0
 
         # Physics manager
-        self.physicsMgr = physicsMgr
+        self.physicsMgr = None
-        integrator = LinearEulerIntegrator()
-        self.physicsMgr.attachLinearIntegrator(integrator)
         self.physicsMgrEnabled = 0
         self.physicsMgrAngular = 0
 
@@ -1362,6 +1357,17 @@ class ShowBase(DirectObject.DirectObject):
 
     def enableParticles(self):
         if not self.particleMgrEnabled:
+            if not self.particleMgr:
+                from direct.particles.ParticleManagerGlobal import particleMgr
+                self.particleMgr = particleMgr
+                self.particleMgr.setFrameStepping(1)
+
+            if not self.physicsMgr:
+                from PhysicsManagerGlobal import physicsMgr
+                self.physicsMgr = physicsMgr
+                integrator = LinearEulerIntegrator()
+                self.physicsMgr.attachLinearIntegrator(integrator)
+
             self.particleMgrEnabled = 1
             self.physicsMgrEnabled = 1
             self.taskMgr.remove('manager-update')

direct/src/showbase/Transitions.py

@@ -6,7 +6,9 @@ __all__ = ['Transitions']
 from pandac.PandaModules import *
 from direct.gui.DirectGui import *
 from direct.task import Task
-from direct.interval.IntervalGlobal import *
+from direct.interval.LerpInterval import LerpColorScaleInterval, LerpColorInterval, LerpScaleInterval, LerpPosInterval
+from direct.interval.MetaInterval import Sequence, Parallel
+from direct.interval.FunctionInterval import Func
 
 class Transitions: