3d viewpoint movement

[spacefarer]

I just tried the script for R2.5 as shown below which was given by Farshid, but it doesn't work with R3. Could anyone tell what's wrong with it, please?

import viz
viz.go()

#Add a ground
viz.add('tut_ground.wrl')

#Get main viewpoint object
view = viz.get(viz.MAIN_VIEWPOINT)

#Create a variable that will tell whether viewpoing is currently moving/turning
view.animating = 0

#Variable that holds current destination value
final = [0,0,0,0]

def rotateview(x,y,z,angle):
#Make sure view is not animating
if not view.animating:
#Compute rotation of turning body 90 degrees to right
xform = viz.Transform(view.get(viz.BODY_MAT))
xform.preRot(x,y,z,angle)
final[:] = xform.getRot()[:]
#Start animating viewpoint
view.spinmask(viz.BODY_ORI) #Spin the body orientation
view.spinto(final,2,viz.TIME) #Spin for 2 seconds
view.animating = 1

def onkeydown(key):
if key == viz.KEY_UP:
#Make sure view is not animating
if not view.animating:
pos = view.get(viz.HEAD_POS)
trans = view.get(viz.BODY_LOOK)
#Round values to nearest integer
final[0] = int(round(pos[0] + trans[0]))
final[1] = int(round(pos[1] + trans[1]))
final[2] = int(round(pos[2] + trans[2]))
#Start animating viewpoint
view.goto(final,1,viz.TIME)
view.animating = 1
elif key == '6': #yaw right
rotateview(0,1,0,90)
elif key == '4': #yaw left
rotateview(0,1,0,-90)
elif key == '8': #pitch up
rotateview(1,0,0,-90)
elif key == '2': #pitch down
rotateview(1,0,0,90)
elif key == '9': #roll right
rotateview(0,0,1,-90)
elif key == '7': #roll left
rotateview(0,0,1,90)

viz.callback(viz.KEYDOWN_EVENT,onkeydown)

def onstop(object, type):
if type == viz.MOVE:
#Viewpoint is done moving, translate it to the final value just to be sure
view.translate(final)
view.animating = 0
elif type == viz.SPIN:
#Viewpoint is done spinning, rotate it to the final value just to be sure
view.rotate(final,viz.BODY_ORI)
view.animating = 0

view.callback(viz.STOP_EVENT,onstop)