SetBatchLines -1 

Height := 600 
Width  := 960 
DiffSpeed := 0.098 
Damping := 0.995 
y := Height 
x := 0 

Gui, Add, Picture, x96 y20 w23 h15 vBalltext Icon1 ,C:\windows\notepad.exe
Gui, Add, Button, x16 y20 w50 h20 gDropping, Drop 
Gui, Add, Button, x16 y50 w50 h20 gStop, Stop 
Gui, Show, x10 y10 h%Height% w%Width%, Gravity Testing 
Return 

GuiClose: 
ExitApp 

Stop: 
SetTimer, falling, off 
GuiControl, Move, Balltext, x96 y20 
return 

Dropping: 
speed := 0.0 
x := 0 
y := Height - 40 
SetTimer, falling, 10 
return 


falling: 
x += 0.5 
If (y < 0) { 
  y *= -1.0 
  speed := Abs(Speed) 
  } 
speed -= DiffSpeed 

y += speed 
y *= Damping 
yposition := (y < 2) ? Height - 20 : Height - y - 20 
xposition := x + 96 
If (xposition > Width-20) 
  Goto Stop 
GuiControl, Move, Balltext, x%xposition% y%yposition% 
return