frame 1
// s1.getDuration()
undefined
// s1.getPosition() > 400
undefined
// s1.getPosition() == 0
false
// s1.duration
undefined
// s1.position > 400
undefined
// s1.position == 0
false

frame 2
// s1.getDuration()
1071
// s1.getPosition() > 400
false
// s1.getPosition() == 0
true
// s1.duration
1071
// s1.position > 400
false
// s1.position == 0
true

frame 3
// s1.getDuration()
1071
// s1.getPosition() > 400
false
// s1.getPosition() == 0
true
// s1.duration
1071
// s1.position > 400
false
// s1.position == 0
true

frame 4
frame 5
