[Visualpython-users] Error with forward and up

[alessandro <bom...@gm...>]

I create 3 icons in my prog.:

Top.view
Front-view
Side-view

I change the forward attribute of my scene (named scena1). I set 
scena1.up = vector (0,0,1) and define 3 func:

def vista_alto(obj):
    global scena1
    scena1.forward = vector(0,0,-1)
   
def vista_fronte(obj):
    global scena1
    scena1.forward = vector(0,-1,0)

def vista_lato(obj):
    global scena1
    scena1.forward = vector(-1,0,0)

but when click on the top-view (1° def) an error appears:

*scena1.forward = vector(-1,0,0)
ValueError: forward may not be colinear with up.*

Reading the documentation I found this requirement but I'm not able to 
solve it. How can I do?

Alessandro Barracco