Some Problem in navigation

[ssaha]

I have been trying to use UserAvatar.py for navigation from link:
http://vizworkshop.com/articles/walkthrough_app

I did two following changes in UserAvatar file:

Change 1: In _init_ function, I used collideBox in place of collideCapsule.

Change 2: In updatePrePhysics, I changed headEuler following way:

headEuler = self.head.getEuler(viz.ABS_GLOBAL)
headEuler[0] = headEuler[0] + yawChange
headEuler[1] = headEuler[1]
headEuler[2] = headEuler[2]
self.head.setEuler(headEuler, viz.ABS_GLOBAL)


Problem: In code, there is no change of y-coordinate of self.feet. According to code, it should be
always zero (0). But when I run the code with above change, I get change in y-coordinate of self.feet. So in order to keep it zero, I add following code in updatePostPhysics:

temp_pos= self.feet.getPosition(viz.ABS_GLOBAL)
temp_pos[1]=0
self.feet.setPosition(temp_pos)


After doing this , y is zero . But movement is not smooth.


Could you give some solutions? For your convenience, updated UserAvatar.py is attached below.



import viz
import vizact
import vizmat
import viztask

class UserAvatar(viz.EventClass):
THROTTLE_SPEED = 4
HYPER_THROTTLE_SPEED = 30
TURN_SPEED = .1
def __init__(self):
viz.EventClass.__init__(self)
self.feet = viz.addGroup(pos=[0, 0, 0]) #position of user avatar

#physics init
self.physicShape = self.feet.collideBox([0.5,1,0.5],friction=.00000001, hardness=.0000001, bounce=0)
self.velMotor = self.feet.addVelocity(velocity=[0,0,0], maxForce=100, gravity=False))

#orientation of user avatar
self.head = viz.addGroup()
#view should link to this
self.avatar = viz.mergeLinkable(self.feet, self.head)
self.count =0;
self.mouseDx = 0
self.mouseDy = 0
self.callback(viz.MOUSE_MOVE_EVENT, self.onMouseMove)

vizact.onupdate(viz.PRIORITY_PHYSICS-1, self.updatePrePhysics)
vizact.onupdate(viz.PRIORITY_PHYSICS+1, self.updatePostPhysics)

def updatePrePhysics(self):
print "count " +str(self.count)
self.count =self.count+1
throttle = vizmat.Vector([0,0,0])
print "vizmat.Vector:Feet Pos: " + str(self.feet.getPosition(viz.ABS_GLOBAL))
## Steer Control
yawChange = self.mouseDx * self.TURN_SPEED
pitchChange = -self.mouseDy * self.TURN_SPEED
#discard old mouse movement and start collecting new mouse input
self.mouseDx = 0
self.mouseDy = 0
'''
headEuler = self.head.getEuler(viz.ABS_GLOBAL)
headEuler[0] = headEuler[0] + yawChange


headEuler[1] = headEuler[1]
headEuler[2] = headEuler[2]

self.head.setEuler(headEuler, viz.ABS_GLOBAL)
'''
## Translate Control
throttle.set([0,0,0])
#forward/back
if viz.key.isDown('w') or viz.mouse.getState() & viz.MOUSEBUTTON_LEFT:
throttle += [0,0,1]
if viz.key.isDown('s') or viz.mouse.getState() & viz.MOUSEBUTTON_RIGHT:
throttle += [0,0,-1]
#left/right
if viz.key.isDown('a'):
throttle += [-1,0,0]
if viz.key.isDown('d'):
throttle += [1,0,0]
throttle.normalize() #<--direction
print "throttle.normalize:Feet Pos: " + str(self.feet.getPosition(viz.ABS_GLOBAL))

print "throttle.length():Feet Pos: " + str(self.feet.getPosition(viz.ABS_GLOBAL))
if viz.key.isDown(' ') or viz.mouse.getState() & viz.MOUSEBUTTON_MIDDLE:
throttle *= self.HYPER_THROTTLE_SPEED
else:
throttle *= self.THROTTLE_SPEED
print "viz.key.isDown:Feet Pos: " + str(self.feet.getPosition(viz.ABS_GLOBAL))
if throttle.length(): #if throttle not zero
#move forward in direction of head
newVel = vizmat.Transform()
newVel.setTrans(throttle)
newVel.postEuler(self.head.getEuler(viz.ABS_GLOBAL ))
self.velMotor.setVelocity(newVel.getTrans())
else:
print "hey"
#self.velMotor.setVelocity([0, 0, 0])

print "throttle.length():Feet Pos: " + str(self.feet.getPosition(viz.ABS_GLOBAL))


def updatePostPhysics(self):

print "updatePostPhysics " + str(self.feet.getPosition(viz.ABS_GLOBAL))
self.feet.setEuler([0, 0, 0])

def onMouseMove(self, e):
#fuction called twice, once for movement on x axis, once for y axis
print "onMouseMove " + str(self.feet.getPosition(viz.ABS_GLOBAL))
self.mouseDx = self.mouseDx + e.dx
self.mouseDy = self.mouseDy + e.dy

def linkView(self, view):
return viz.link(self.avatar, view, srcFlag=viz.LINK_ABSOLUTE, dstFlag=viz.LINK_POS_RAW)

def setPosition(self, xyz):
self.feet.setPosition(xyz)
print "setPosition " + str(self.feet.getPosition(viz.ABS_GLOBAL))

def setEuler(self, euler):
self.head.setEuler(euler)

if __name__ == '__main__':
viz.go()
viz.move([0, 0, -2])
viz.phys.enable()
t = viz.add('tankmaze.wrl')
t.collideMesh(bounce=0, hardness=1, friction=0)
user = UserAvatar()
user.feet.setPosition([0, 0, 0])
user.linkView(viz.MainView)