hmmm
var constant dec = 0.2 // fiddle to speed
var constant pwr = 10
var speed = gamepad.x * pwr
if (speed < sprite.currentspeed)
{
sprite.currentspeed = lerp(sprite.currentspeed, speed, dec)
}
else if (speed > sprite.currentspeed)
{
sprite.currentspeed = speed
}
ummmm. will that work based on what your looking for; or at least maybe some inspiration to solve your problem. It's not fined tuned too work 100%. I'm just brainstorming.