A ShipPilot is a control for steering a ship

direct/src/controls/ShipPilot.py

@@ -0,0 +1,709 @@
+"""
+ShipPilot.py is for avatars pilotting ships (or more accurately, a ship as the avatar).
+
+A control such as this one provides:
+    - creation of the collision nodes
+    - handling the keyboard and mouse input for avatar movement
+    - moving the avatar
+
+it does not:
+    - play sounds
+    - play animations
+
+although it does send messeges that allow a listener to play sounds or
+animations based on control events.
+"""
+
+from direct.showbase.ShowBaseGlobal import *
+
+from direct.directnotify import DirectNotifyGlobal
+from pandac import PhysicsManager
+import math
+
+import PhysicsWalker
+
+#import LineStream
+
+class ShipPilot(PhysicsWalker.PhysicsWalker):
+
+    notify = DirectNotifyGlobal.directNotify.newCategory("PhysicsWalker")
+    wantAvatarPhysicsIndicator = base.config.GetBool('want-avatar-physics-indicator', 0)
+    
+    useLifter = 0
+    useHeightRay = 0
+    
+    # special methods
+    def __init__(self, gravity = -32.1740, standableGround=0.707,
+            hardLandingForce=16.0):
+        assert(self.debugPrint("PhysicsWalker(gravity=%s, standableGround=%s)"%(
+                gravity, standableGround)))
+        PhysicsWalker.PhysicsWalker.__init__(self, gravity = -32.1740, standableGround=0.707,
+            hardLandingForce=16.0)
+        self.__gravity=gravity
+        self.__standableGround=standableGround
+        self.__hardLandingForce=hardLandingForce
+        
+        self.needToDeltaPos = 0
+        self.physVelocityIndicator=None
+        self.avatarControlForwardSpeed=0
+        self.avatarControlJumpForce=0
+        self.avatarControlReverseSpeed=0
+        self.avatarControlRotateSpeed=0
+        self.__oldAirborneHeight=None
+        self.getAirborneHeight=None
+        self.__oldContact=None
+        self.__oldPosDelta=Vec3(0)
+        self.__oldDt=0
+        self.__speed=0.0
+        self.__rotationSpeed=0.0
+        self.__slideSpeed=0.0
+        self.__vel=Vec3(0.0)
+        self.collisionsActive = 0
+        
+        self.isAirborne = 0
+        self.highMark = 0
+
+    def setWalkSpeed(self, forward, jump, reverse, rotate):
+        assert(self.debugPrint("setWalkSpeed()"))
+        self.avatarControlForwardSpeed=forward
+        self.avatarControlJumpForce=0.0
+        self.avatarControlReverseSpeed=reverse
+        self.avatarControlRotateSpeed=rotate
+
+    def getSpeeds(self):
+        #assert(self.debugPrint("getSpeeds()"))
+        return (self.__speed, self.__rotationSpeed)
+
+    def setupRay(self, floorBitmask, floorOffset):
+        # This is a ray cast from your head down to detect floor polygons
+        # A toon is about 4.0 feet high, so start it there
+        self.cRay = CollisionRay(0.0, 0.0, CollisionHandlerRayStart, 0.0, 0.0, -1.0)
+        cRayNode = CollisionNode('PW.cRayNode')
+        cRayNode.addSolid(self.cRay)
+        self.cRayNodePath = self.avatarNodePath.attachNewNode(cRayNode)
+        self.cRayBitMask = floorBitmask
+        cRayNode.setFromCollideMask(self.cRayBitMask)
+        cRayNode.setIntoCollideMask(BitMask32.allOff())
+
+        if 0 or self.useLifter:
+            # set up floor collision mechanism
+            self.lifter = CollisionHandlerFloor()
+            self.lifter.setInPattern("enter%in")
+            self.lifter.setOutPattern("exit%in")
+            self.lifter.setOffset(floorOffset)
+
+            # Limit our rate-of-fall with the lifter.
+            # If this is too low, we actually "fall" off steep stairs
+            # and float above them as we go down. I increased this
+            # from 8.0 to 16.0 to prevent this
+            #self.lifter.setMaxVelocity(16.0)
+
+            #self.bobNodePath = self.avatarNodePath.attachNewNode("bob")
+            #self.lifter.addCollider(self.cRayNodePath, self.cRayNodePath)
+            self.lifter.addCollider(self.cRayNodePath, self.avatarNodePath)
+        else: # useCollisionHandlerQueue
+            self.cRayQueue = CollisionHandlerQueue()
+            self.cTrav.addCollider(self.cRayNodePath, self.cRayQueue)
+
+    def determineHeight(self):
+        """
+        returns the height of the avatar above the ground.
+        If there is no floor below the avatar, 0.0 is returned.
+        aka get airborne height.
+        """
+        if self.useLifter:
+            height = self.avatarNodePath.getPos(self.cRayNodePath)
+            # If the shadow where not pointed strait down, we would need to
+            # get magnitude of the vector.  Since it is strait down, we'll
+            # just get the z:
+            #spammy --> assert self.debugPrint("getAirborneHeight() returning %s"%(height.getZ(),))
+            assert onScreenDebug.add("height", height.getZ())
+            return height.getZ() - self.floorOffset
+        else: # useCollisionHandlerQueue
+            """
+            returns the height of the avatar above the ground.
+            If there is no floor below the avatar, 0.0 is returned.
+            aka get airborne height.
+            """
+            height = 0.0
+            #*#self.cRayTrav.traverse(render)
+            if self.cRayQueue.getNumEntries() != 0:
+                # ...we have a floor.
+                # Choose the highest of the possibly several floors we're over:
+                self.cRayQueue.sortEntries()
+                floorPoint = self.cRayQueue.getEntry(0).getFromIntersectionPoint()
+                height = -floorPoint.getZ()
+            self.cRayQueue.clearEntries()
+            if __debug__:
+                onScreenDebug.add("height", height)
+            return height
+
+    def setupSphere(self, bitmask, avatarRadius):
+        """
+        Set up the collision sphere
+        """
+        # This is a sphere on the ground to detect barrier collisions
+        self.avatarRadius = avatarRadius
+        centerHeight = avatarRadius
+        if self.useHeightRay:
+            centerHeight *= 2.0
+        self.cSphere = CollisionSphere(0.0, 0.0, centerHeight, avatarRadius)
+        cSphereNode = CollisionNode('PW.cSphereNode')
+        cSphereNode.addSolid(self.cSphere)
+        self.cSphereNodePath = self.avatarNodePath.attachNewNode(cSphereNode)
+        self.cSphereBitMask = bitmask
+
+        cSphereNode.setFromCollideMask(self.cSphereBitMask)
+        cSphereNode.setIntoCollideMask(BitMask32.allOff())
+
+        # set up collision mechanism
+        self.pusher = PhysicsCollisionHandler()
+        self.pusher.setInPattern("enter%in")
+        self.pusher.setOutPattern("exit%in")
+
+        self.pusher.addCollider(self.cSphereNodePath, self.avatarNodePath)
+
+    def setupPhysics(self, avatarNodePath):
+        assert(self.debugPrint("setupPhysics()"))
+        # Connect to Physics Manager:
+        self.actorNode=ActorNode("physicsActor")
+        self.actorNode.getPhysicsObject().setOriented(1)
+        self.actorNode.getPhysical(0).setViscosity(0.1)
+        physicsActor=NodePath(self.actorNode)
+        avatarNodePath.reparentTo(physicsActor)
+        avatarNodePath.assign(physicsActor)
+        self.phys=PhysicsManager.PhysicsManager()
+
+        fn=ForceNode("gravity")
+        fnp=NodePath(fn)
+        #fnp.reparentTo(physicsActor)
+        fnp.reparentTo(render)
+        gravity=LinearVectorForce(0.0, 0.0, self.__gravity)
+        fn.addForce(gravity)
+        self.phys.addLinearForce(gravity)
+        self.gravity = gravity
+
+        fn=ForceNode("priorParent")
+        fnp=NodePath(fn)
+        fnp.reparentTo(render)
+        priorParent=LinearVectorForce(0.0, 0.0, 0.0)
+        fn.addForce(priorParent)
+        self.phys.addLinearForce(priorParent)
+        self.priorParentNp = fnp
+        self.priorParent = priorParent
+
+        fn=ForceNode("viscosity")
+        fnp=NodePath(fn)
+        #fnp.reparentTo(physicsActor)
+        fnp.reparentTo(render)
+        self.avatarViscosity=LinearFrictionForce(0.0, 1.0, 0)
+        #self.avatarViscosity.setCoef(0.9)
+        fn.addForce(self.avatarViscosity)
+        self.phys.addLinearForce(self.avatarViscosity)
+
+        self.phys.attachLinearIntegrator(LinearEulerIntegrator())
+        self.phys.attachPhysicalnode(physicsActor.node())
+
+        self.acForce=LinearVectorForce(0.0, 0.0, 0.0)
+        fn=ForceNode("avatarControls")
+        fnp=NodePath(fn)
+        fnp.reparentTo(render)
+        fn.addForce(self.acForce)
+        self.phys.addLinearForce(self.acForce)
+        #self.phys.removeLinearForce(self.acForce)
+        #fnp.remove()
+        return avatarNodePath
+
+    def initializeCollisions(self, collisionTraverser, avatarNodePath, 
+            wallBitmask, floorBitmask, 
+            avatarRadius = 1.4, floorOffset = 1.0, reach = 1.0):
+        """
+        Set up the avatar collisions
+        """
+        assert(self.debugPrint("initializeCollisions()"))
+        
+        assert not avatarNodePath.isEmpty()
+        
+        self.cTrav = collisionTraverser
+        self.floorOffset = floorOffset = 7.0
+
+        self.avatarNodePath = self.setupPhysics(avatarNodePath)
+        if 0 or self.useHeightRay:
+            #self.setupRay(floorBitmask, avatarRadius)
+            self.setupRay(floorBitmask, 0.0)
+        self.setupSphere(wallBitmask|floorBitmask, avatarRadius)
+
+        self.setCollisionsActive(1)
+
+    def setAirborneHeightFunc(self, getAirborneHeight):
+        self.getAirborneHeight = getAirborneHeight
+
+    def setAvatarPhysicsIndicator(self, indicator):
+        """
+        indicator is a NodePath
+        """
+        assert(self.debugPrint("setAvatarPhysicsIndicator()"))
+        self.cSphereNodePath.show()
+        if indicator:
+            # Indicator Node:
+            change=render.attachNewNode("change")
+            #change.setPos(Vec3(1.0, 1.0, 1.0))
+            #change.setHpr(0.0, 0.0, 0.0)
+            change.setScale(0.1)
+            #change.setColor(Vec4(1.0, 1.0, 1.0, 1.0))
+            indicator.reparentTo(change)
+
+            indicatorNode=render.attachNewNode("physVelocityIndicator")
+            #indicatorNode.setScale(0.1)
+            #indicatorNode.setP(90.0)
+            indicatorNode.setPos(self.avatarNodePath, 0.0, 0.0, 6.0)
+            indicatorNode.setColor(0.0, 0.0, 1.0, 1.0)
+            change.reparentTo(indicatorNode)
+
+            self.physVelocityIndicator=indicatorNode
+            # Contact Node:
+            contactIndicatorNode=render.attachNewNode("physContactIndicator")
+            contactIndicatorNode.setScale(0.25)
+            contactIndicatorNode.setP(90.0)
+            contactIndicatorNode.setPos(self.avatarNodePath, 0.0, 0.0, 5.0)
+            contactIndicatorNode.setColor(1.0, 0.0, 0.0, 1.0)
+            indicator.instanceTo(contactIndicatorNode)
+            self.physContactIndicator=contactIndicatorNode
+        else:
+            print "failed load of physics indicator"
+
+    def avatarPhysicsIndicator(self, task):
+        #assert(self.debugPrint("avatarPhysicsIndicator()"))
+        # Velocity:
+        self.physVelocityIndicator.setPos(self.avatarNodePath, 0.0, 0.0, 6.0)
+        physObject=self.actorNode.getPhysicsObject()
+        a=physObject.getVelocity()
+        self.physVelocityIndicator.setScale(math.sqrt(a.length()))
+        a+=self.physVelocityIndicator.getPos()
+        self.physVelocityIndicator.lookAt(Point3(a))
+        # Contact:
+        contact=self.actorNode.getContactVector()
+        if contact==Vec3.zero():
+            self.physContactIndicator.hide()
+        else:
+            self.physContactIndicator.show()
+            self.physContactIndicator.setPos(self.avatarNodePath, 0.0, 0.0, 5.0)
+            #contact=self.actorNode.getContactVector()
+            point=Point3(contact+self.physContactIndicator.getPos())
+            self.physContactIndicator.lookAt(point)
+        return Task.cont
+
+    def deleteCollisions(self):
+        assert(self.debugPrint("deleteCollisions()"))
+        del self.cTrav
+
+        if self.useHeightRay:
+            del self.cRayQueue
+            self.cRayNodePath.removeNode()
+            del self.cRayNodePath
+
+        del self.cSphere
+        self.cSphereNodePath.removeNode()
+        del self.cSphereNodePath
+
+        del self.pusher
+        
+        del self.getAirborneHeight
+
+    def setCollisionsActive(self, active = 1):
+        assert(self.debugPrint("collisionsActive(active=%s)"%(active,)))
+        if self.collisionsActive != active:
+            self.collisionsActive = active
+            if active:
+                self.cTrav.addCollider(self.cSphereNodePath, self.pusher)
+                if self.useHeightRay:
+                    if self.useLifter:
+                        self.cTrav.addCollider(self.cRayNodePath, self.lifter)
+                    else:
+                        self.cTrav.addCollider(self.cRayNodePath, self.cRayQueue)
+            else:
+                self.cTrav.removeCollider(self.cSphereNodePath)
+                if self.useHeightRay:
+                    self.cTrav.removeCollider(self.cRayNodePath)
+                # Now that we have disabled collisions, make one more pass
+                # right now to ensure we aren't standing in a wall.
+                self.oneTimeCollide()
+
+    def getCollisionsActive(self):
+        assert(self.debugPrint("getCollisionsActive() returning=%s"%(
+            self.collisionsActive,)))
+        return self.collisionsActive
+    
+    def placeOnFloor(self):
+        """
+        Make a reasonable effort to place the avatar on the ground.
+        For example, this is useful when switching away from the 
+        current walker.
+        """
+        self.oneTimeCollide()
+        self.avatarNodePath.setZ(self.avatarNodePath.getZ()-self.getAirborneHeight())
+
+    def oneTimeCollide(self):
+        """
+        Makes one quick collision pass for the avatar, for instance as
+        a one-time straighten-things-up operation after collisions
+        have been disabled.
+        """
+        assert(self.debugPrint("oneTimeCollide()"))
+        tempCTrav = CollisionTraverser("oneTimeCollide")
+        if self.useHeightRay:
+            if self.useLifter:
+                tempCTrav.addCollider(self.cRayNodePath, self.lifter)
+            else:
+                tempCTrav.addCollider(self.cRayNodePath, self.cRayQueue)
+        tempCTrav.traverse(render)
+
+    def handleAvatarControls(self, task):
+        """
+        Check on the arrow keys and update the avatar.
+        """
+        if __debug__:
+            if self.wantAvatarPhysicsIndicator:
+                onScreenDebug.append("localAvatar pos = %s\n"%(base.localAvatar.getPos().pPrintValues(),))
+                onScreenDebug.append("localAvatar h = % 10.4f\n"%(base.localAvatar.getH(),))
+                onScreenDebug.append("localAvatar anim = %s\n"%(base.localAvatar.animFSM.getCurrentState().getName(),))
+        #assert(self.debugPrint("handleAvatarControls(task=%s)"%(task,)))
+        physObject=self.actorNode.getPhysicsObject()
+        #rotAvatarToPhys=Mat3.rotateMatNormaxis(-self.avatarNodePath.getH(), Vec3.up())
+        #rotPhysToAvatar=Mat3.rotateMatNormaxis(self.avatarNodePath.getH(), Vec3.up())
+        contact=self.actorNode.getContactVector()
+        
+        # hack fix for falling through the floor:
+        if contact==Vec3.zero() and self.avatarNodePath.getZ()<-50.0:
+            # DCR: don't reset X and Y; allow player to move
+            self.reset()
+            self.avatarNodePath.setZ(50.0)
+            messenger.send("walkerIsOutOfWorld", [self.avatarNodePath])
+
+        # get the button states:
+        forward = inputState.isSet("forward")
+        reverse = inputState.isSet("reverse")
+        turnLeft = inputState.isSet("turnLeft")
+        turnRight = inputState.isSet("turnRight")
+        slide = 0#inputState.isSet("slide")
+        slideLeft = 0#inputState.isSet("slideLeft")
+        slideRight = 0#inputState.isSet("slideRight")
+        jump = inputState.isSet("jump")
+        # Determine what the speeds are based on the buttons:
+        self.__speed=(forward and self.avatarControlForwardSpeed or 
+                reverse and -self.avatarControlReverseSpeed)
+        avatarSlideSpeed=self.avatarControlForwardSpeed*0.5
+        #self.__slideSpeed=slide and (
+        #        (turnLeft and -avatarSlideSpeed) or 
+        #        (turnRight and avatarSlideSpeed))
+        self.__slideSpeed=(
+                (slideLeft and -avatarSlideSpeed) or 
+                (slideRight and avatarSlideSpeed))
+        self.__rotationSpeed=not slide and (
+                (turnLeft and self.avatarControlRotateSpeed) or
+                (turnRight and -self.avatarControlRotateSpeed))
+
+        # How far did we move based on the amount of time elapsed?
+        dt=ClockObject.getGlobalClock().getDt()
+
+        if self.needToDeltaPos:
+            self.setPriorParentVector()
+            self.needToDeltaPos = 0
+        #self.__oldPosDelta = render.getRelativeVector(
+        #    self.avatarNodePath,
+        #    self.avatarNodePath.getPosDelta(render))
+        #self.__oldPosDelta = self.avatarNodePath.getRelativeVector(
+        #    render,
+        #    self.avatarNodePath.getPosDelta(render))
+        self.__oldPosDelta = self.avatarNodePath.getPosDelta(render)
+        self.__oldDt = dt
+        #posDelta = self.avatarNodePath.getPosDelta(render)
+        #if posDelta==Vec3.zero():
+        #    self.priorParent.setVector(self.__oldPosDelta)
+        #else:
+        #    self.priorParent.setVector(Vec3.zero())
+        #    # We must copy the vector to preserve it:
+        #    self.__oldPosDelta=Vec3(posDelta)
+        if __debug__:
+            if self.wantAvatarPhysicsIndicator:
+                onScreenDebug.add("posDelta1",
+                    self.avatarNodePath.getPosDelta(render).pPrintValues())
+                
+                if 0:
+                    onScreenDebug.add("posDelta3",
+                        render.getRelativeVector(
+                            self.avatarNodePath,
+                            self.avatarNodePath.getPosDelta(render)).pPrintValues())
+                
+                if 0:
+                    onScreenDebug.add("gravity",
+                        self.gravity.getLocalVector().pPrintValues())
+                    onScreenDebug.add("priorParent",
+                        self.priorParent.getLocalVector().pPrintValues())
+                    onScreenDebug.add("avatarViscosity",
+                        "% 10.4f"%(self.avatarViscosity.getCoef(),))
+                    
+                    onScreenDebug.add("physObject pos",
+                        physObject.getPosition().pPrintValues())
+                    onScreenDebug.add("physObject hpr",
+                        physObject.getOrientation().getHpr().pPrintValues())
+                    onScreenDebug.add("physObject orien",
+                        physObject.getOrientation().pPrintValues())
+
+                if 1:
+                    onScreenDebug.add("physObject vel",
+                        physObject.getVelocity().pPrintValues())
+                    onScreenDebug.add("physObject len",
+                        "% 10.4f"%physObject.getVelocity().length())
+
+                if 0:
+                    onScreenDebug.add("posDelta4", 
+                        self.priorParentNp.getRelativeVector(
+                            render,
+                            self.avatarNodePath.getPosDelta(render)).pPrintValues())
+
+                if 1:
+                    onScreenDebug.add("priorParent",
+                        self.priorParent.getLocalVector().pPrintValues())
+
+                if 0:
+                    onScreenDebug.add("priorParent po",
+                        self.priorParent.getVector(physObject).pPrintValues())
+
+                if 0:
+                    onScreenDebug.add("__posDelta",
+                        self.__oldPosDelta.pPrintValues())
+
+                if 1:
+                    onScreenDebug.add("contact",
+                        contact.pPrintValues())
+                    #onScreenDebug.add("airborneHeight", "% 10.4f"%(
+                    #    self.getAirborneHeight(),))
+
+                if 0:
+                    onScreenDebug.add("__oldContact",
+                        contact.pPrintValues())
+                    onScreenDebug.add("__oldAirborneHeight", "% 10.4f"%(
+                        self.getAirborneHeight(),))
+        airborneHeight=self.getAirborneHeight()
+        if airborneHeight > self.highMark:
+            self.highMark = airborneHeight
+            if __debug__:
+                onScreenDebug.add("highMark", "% 10.4f"%(self.highMark,))
+        #if airborneHeight < 0.1: #contact!=Vec3.zero():
+        if 1:
+            if (airborneHeight > self.avatarRadius*0.5
+                    or physObject.getVelocity().getZ() > 0.0
+                    ): # Check stair angles before changing this.
+                # ...the avatar is airborne (maybe a lot or a tiny amount).
+                self.isAirborne = 1
+            else:
+                # ...the avatar is very close to the ground (close enough to be
+                # considered on the ground).
+                if self.isAirborne and physObject.getVelocity().getZ() <= 0.0:
+                    # ...the avatar has landed.
+                    contactLength = contact.length()
+                    if contactLength>self.__hardLandingForce:
+                        #print "jumpHardLand"
+                        messenger.send("jumpHardLand")
+                    else:
+                        #print "jumpLand"
+                        messenger.send("jumpLand")
+                    self.priorParent.setVector(Vec3.zero())
+                    self.isAirborne = 0
+                elif jump:
+                    #print "jump"
+                    #self.__jumpButton=0
+                    messenger.send("jumpStart")
+                    if 0:
+                        # ...jump away from walls and with with the slope normal.
+                        jumpVec=Vec3(contact+Vec3.up())
+                        #jumpVec=Vec3(rotAvatarToPhys.xform(jumpVec))
+                        jumpVec.normalize()
+                    else:
+                        # ...jump straight up, even if next to a wall.
+                        jumpVec=Vec3.up()
+                    jumpVec*=self.avatarControlJumpForce
+                    physObject.addImpulse(Vec3(jumpVec))
+                    self.isAirborne = 1 # Avoid double impulse before fully airborne.
+                else:
+                    self.isAirborne = 0
+            if __debug__:
+                onScreenDebug.add("isAirborne", "%d"%(self.isAirborne,))
+        else:
+            if contact!=Vec3.zero():
+                # ...the avatar has touched something (but might not be on the ground).
+                contactLength = contact.length()
+                contact.normalize()
+                angle=contact.dot(Vec3.up())
+                if angle>self.__standableGround:
+                    # ...avatar is on standable ground.
+                    if self.__oldContact==Vec3.zero():
+                    #if self.__oldAirborneHeight > 0.1: #self.__oldContact==Vec3.zero():
+                        # ...avatar was airborne.
+                        self.jumpCount-=1
+                        if contactLength>self.__hardLandingForce:
+                            messenger.send("jumpHardLand")
+                        else:
+                            messenger.send("jumpLand")
+                    elif jump:
+                        self.jumpCount+=1
+                        #self.__jumpButton=0
+                        messenger.send("jumpStart")
+                        jump=Vec3(contact+Vec3.up())
+                        #jump=Vec3(rotAvatarToPhys.xform(jump))
+                        jump.normalize()
+                        jump*=self.avatarControlJumpForce
+                        physObject.addImpulse(Vec3(jump))
+
+        if contact!=self.__oldContact:
+            # We must copy the vector to preserve it:
+            self.__oldContact=Vec3(contact)
+        self.__oldAirborneHeight=airborneHeight
+
+        moveToGround = Vec3.zero()
+        if not self.useHeightRay or self.isAirborne: 
+            # ...the airborne check is a hack to stop sliding.
+            self.phys.doPhysics(dt)
+            if __debug__:
+                onScreenDebug.add("phys", "on")
+        else:
+            physObject.setVelocity(Vec3.zero())
+            #if airborneHeight>0.001 and contact==Vec3.zero():
+            #    moveToGround = Vec3(0.0, 0.0, -airborneHeight)
+            #moveToGround = Vec3(0.0, 0.0, -airborneHeight)
+            moveToGround = Vec3(0.0, 0.0, -self.determineHeight())
+            if __debug__:       
+                onScreenDebug.add("phys", "off")
+        # Check to see if we're moving at all:
+        if self.__speed or self.__slideSpeed or self.__rotationSpeed or moveToGround!=Vec3.zero():
+            distance = dt * self.__speed
+            slideDistance = dt * self.__slideSpeed
+            rotation = dt * self.__rotationSpeed
+
+            #debugTempH=self.avatarNodePath.getH()
+            assert self.avatarNodePath.getQuat().isSameDirection(physObject.getOrientation())
+            assert self.avatarNodePath.getPos().almostEqual(physObject.getPosition(), 0.0001)
+            
+            # update pos:
+            # Take a step in the direction of our previous heading.
+            self.__vel=Vec3(
+                Vec3.forward() * distance + 
+                Vec3.right() * slideDistance)
+            
+            # rotMat is the rotation matrix corresponding to
+            # our previous heading.
+            rotMat=Mat3.rotateMatNormaxis(self.avatarNodePath.getH(), Vec3.up())
+            step=rotMat.xform(self.__vel)
+
+            newVector = self.acForce.getLocalVector()+Vec3(step*100.0)
+            maxLen = 500.0
+            if newVector.length() > maxLen:
+                newVector.normalize()
+                newVector *= maxLen
+            onScreenDebug.add("newVector",
+                newVector)
+            onScreenDebug.add("newVector length",
+                newVector.length())
+            self.acForce.setVector(Vec3(newVector))
+            #physObject.setPosition(Point3(
+            #    physObject.getPosition()+step+moveToGround))
+
+            # update hpr:
+            o=physObject.getOrientation()
+            r=LRotationf()
+            r.setHpr(Vec3(rotation, 0.0, 0.0))
+            physObject.setOrientation(o*r)
+
+            # sync the change:
+            self.actorNode.updateTransform()
+
+            assert self.avatarNodePath.getQuat().isSameDirection(physObject.getOrientation())
+            assert self.avatarNodePath.getPos().almostEqual(physObject.getPosition(), 0.0001)
+            #assert self.avatarNodePath.getH()==debugTempH-rotation
+            messenger.send("avatarMoving")
+        else:
+            self.__vel.set(0.0, 0.0, 0.0)
+        # Clear the contact vector so we can tell if we contact something next frame:
+        self.actorNode.setContactVector(Vec3.zero())
+        return Task.cont
+    
+    def doDeltaPos(self):
+        assert(self.debugPrint("doDeltaPos()"))
+        self.needToDeltaPos = 1
+    
+    def setPriorParentVector(self):
+        assert(self.debugPrint("doDeltaPos()"))
+        
+        print "self.__oldDt", self.__oldDt, "self.__oldPosDelta", self.__oldPosDelta
+        if __debug__:
+            onScreenDebug.add("__oldDt", "% 10.4f"%self.__oldDt)
+            onScreenDebug.add("self.__oldPosDelta",
+                              self.__oldPosDelta.pPrintValues())
+        
+        velocity = self.__oldPosDelta*(1/self.__oldDt)*4.0 # *4.0 is a hack
+        assert(self.debugPrint("  __oldPosDelta=%s"%(self.__oldPosDelta,)))
+        assert(self.debugPrint("  velocity=%s"%(velocity,)))
+        self.priorParent.setVector(Vec3(velocity))
+        if __debug__:
+            if self.wantAvatarPhysicsIndicator:
+                onScreenDebug.add("velocity", velocity.pPrintValues())
+    
+    def reset(self):
+        assert(self.debugPrint("reset()"))
+        self.actorNode.getPhysicsObject().resetPosition(self.avatarNodePath.getPos())
+        self.priorParent.setVector(Vec3.zero())
+        self.highMark = 0
+        self.actorNode.setContactVector(Vec3.zero())
+        if __debug__:
+            contact=self.actorNode.getContactVector()
+            onScreenDebug.add("priorParent po",
+                self.priorParent.getVector(self.actorNode.getPhysicsObject()).pPrintValues())
+            onScreenDebug.add("highMark", "% 10.4f"%(self.highMark,))
+            onScreenDebug.add("contact", contact.pPrintValues())
+
+    def enableAvatarControls(self):
+        """
+        Activate the arrow keys, etc.
+        """
+        assert(self.debugPrint("enableAvatarControls()"))
+        assert self.collisionsActive
+
+        if __debug__:
+            #self.accept("control-f3", self.spawnTest) #*#
+            self.accept("f3", self.reset) # for debugging only.
+
+        taskName = "AvatarControls-%s"%(id(self),)
+        # remove any old
+        taskMgr.remove(taskName)
+        # spawn the new task
+        taskMgr.add(self.handleAvatarControls, taskName, 25)
+        if self.physVelocityIndicator:
+            taskMgr.add(self.avatarPhysicsIndicator, "AvatarControlsIndicator%s"%(id(self),), 35)
+
+    def disableAvatarControls(self):
+        """
+        Ignore the arrow keys, etc.
+        """
+        assert(self.debugPrint("disableAvatarControls()"))
+        taskName = "AvatarControls-%s"%(id(self),)
+        taskMgr.remove(taskName)
+
+        taskName = "AvatarControlsIndicator%s"%(id(self),)
+        taskMgr.remove(taskName)
+
+        if __debug__:
+            self.ignore("control-f3") #*#
+            self.ignore("f3")
+
+    
+    if __debug__:
+        def setupAvatarPhysicsIndicator(self):
+            if self.wantAvatarPhysicsIndicator:
+                indicator=loader.loadModelCopy('phase_5/models/props/dagger')
+                #self.walkControls.setAvatarPhysicsIndicator(indicator)
+
+        def debugPrint(self, message):
+            """for debugging"""
+            return self.notify.debug(
+                    str(id(self))+' '+message)