this is a helicopter flying in a star night.

the commands are:

"t" make the helicopter goes foward

"g" make it goes backward

"i" increase the rotating speed of the helicopter fan 

"o" decrease the rotating speed of the helicopter fan

"k" increase the moving speed of the helicopter

"l" decrease the moving speed of the helicopter

"1" turn the light on/off


    The helicopter can only move a little bit, i tried to make it move faster 
or slower by moving the the objects around it. The background is a moon with 
some star located far aways in negative z axis.

    The helicopter can move in two ways( toward the viewer or away from the view)
by using t and g keys, when press t, the helicopter will turn it's head downward 
by 20 degree automatically.

    Also when user change the moving direction, it will stop moving and turn 180 
degree automatically.

    For ligting i use white light and a yellow light, and place the light sources
at the direction of the textrue map.