It cool program IT FOR BOTH DARKBASIC PRO AND DARKBASIC

You can control the bounce and it automatic bounce on it own but u can change different way.

                                    ` This code was downloaded from The Game Creators
                                    ` It is reproduced here with full permission
                                    ` http://www.thegamecreators.com
                                    
                                    remstart
------------------------------------
  Double Square Program verison .5
------------------------------------
remend

` Turn on the sync
sync on
sync rate 200

` Make Variable
x=20
y=25
xx=205
yy=207
addx=1
addy=1
addxx=1
addyy=1

` The main Program
do
sync
sleep 1
cls

line 5,5,200,5
line 5,5,5,200
line 200,5,200,200
line 5,200,200,200

line 205,5,400,5
line 205,5,205,400
line 400,5,400,400
line 205,400,400,400

dot x#,y#
dot xx#,yy#

x#=x#+xadd#
y#=y+yadd#
xx#=xx#+xadd#
yy#=yy#+yadd#

if x#=5
xadd#=1
endif

if x#=200
xadd#=-1
endif

if x#=5
xadd#=1
endif

if xx#=205
xxadd#=1
endif

if xx#=400
xxadd#=-1
endif

if yy#=5
yyadd#=1
endif

if yy#=400
yyadd#=-1
endif

loop