Rem ************************************ 
Rem *        AMOS Example 12.5         * 
Rem *          Bob Clear/Draw          *     
Rem *    (c) Mandarin / Jawx 1990      * 
Rem ************************************ 
Rem
Rem Open two screens with four colours   
Screen Open 0,320,256,4,Lowres
Screen Open 1,320,256,4,Lowres
Rem Set a nicely subdued palette (to avoid headaches!) 
Flash Off : Palette 0,$666,$888,$AAA
Curs Off : Hide 
Rem make a bob image 
MAKE_OBJECTS
Rem Initialize screen
Rem Draw a random pattern
MAKE_PATTERN
Rem Initialise screen zero 
Screen Copy 1 To 0 : Screen 0 : Screen To Front 0
Flash Off : Get Palette 1
Rem activate screen swtiching and turn off bob updates 
Double Buffer : Bob Update Off 
Rem Set scrolling size 
S=4
Repeat 
   Rem keep logical and physical screens in step
   For Y=0 To 240-S Step S
      Rem remove bobs from screen
      Bob Clear 
      Rem scroll screen
      Screen Copy 1,79,Y+S*2,240,240 To 0,79,0 : Rem scroll screen
      Screen Copy 1,79,0,240,Y+S*2 To 0,79,240-(Y+S*2)
      Bob 1,X Screen(X Mouse),Y Screen(Y Mouse),1
      Rem redraw bobs at new position  
      Bob Draw 
      Screen Swap : Wait Vbl 
   Next Y
   Rem Boom 
Until Mouse Key
Procedure MAKE_OBJECTS
   Rem Generate an image
   Cls 0
   Rem Ship 
   Ink 2
   Polygon 8,0 To 16,16 To 0,16 To 8,0
   Ink 0
   Polygon 8,10 To 16,16 To 0,16 To 8,10
   Get Bob 1,0,0 To 16,16
End Proc
Procedure MAKE_PATTERN
   Cls 0
   For S=0 To 11
      Rem choose a colour
      I=S mod 4 : Ink I
      Bar 80,S*20 To 239,S*20+19
   Next S
End Proc