Got a question about my.u

i want to move the skin on a entity
i need this for an energybar
with "my.u=1*time_step;" the skin will move non stop
but how can i handle the way move from 100% to 80% and stop to
move?

example:

var move_u;
my.u = move_u*time_step;

now you just need to manipulate move_u, then you set it to 0, then skin will stop moving

tnx, i got it