enter
> program
 size 1200 600 
 paper 55 55 55
 
 set rseed <time 4>
 set bb (198621+<time 4>)
 set mm (98621+<time 4>)
 
 fast
 number random n
 {
    set bl (rseed*bb+1)
    set rseed (bl % mm)
    value (rseed % n)
 }
 
 //command rects x y w h r g b
 //{
 //   pen r g b
 //   repeat w1 (0) 10
 //   {
 //      pen r g b
 //      line (x) (y+h+w1) (x+w) (y+h+w1)
 //   }
 //}
 fast
 command squ x y h r g b  //萬用正方形
 {
    repeat i 0 x
    {
       pen 20
       line (<mouse 1>+i)(<mouse 2>)(<mouse 1>+i)(<mouse 2>+y)
       pen r g b
       line (<mouse 1>+i)(<mouse 2>+y)(<mouse 1>+i)(<mouse 2>+h)
 pen 100
 line<mouse 1><mouse 2><mouse 1>(<mouse 2>+h) 
 line<mouse 1><mouse 2>(<mouse 1>+x)<mouse 2>
 line<mouse 1>(<mouse 2>+h)(<mouse 1>+x)(<mouse 2>+h)
 line<mouse 1>(<mouse 2>+y)(<mouse 1>+x)(<mouse 2>+y)
 line(<mouse 1>+x)(<mouse 2>+h)(<mouse 1>+x)<mouse 2>
    }
 
 }
 
 command bl  //黑框
 {
 
 }
 
 forever
 {
    same?<mouse 3>100 // 滑鼠按下才會開始動
    {
 
       fast
       //rects <mouse 1> <mouse 2> 90 70 <random 100><random 100><random 100>
       fast
       squ 250 160 180 <random 100> <random 100>  <random 100>
       // pen 100
 
       // field <mouse 1> <mouse 2> (<mouse 1>+90) (<mouse 2>+70) <random 100>
       // line <mouse 1> <mouse 2> (<mouse 1>+90)  <mouse 2>
       // line <mouse 1> <mouse 2> <mouse 1> (<mouse 2>+80)
       // line <mouse 1> (<mouse 2>+70) (<mouse 1>+90) (<mouse 2>+70)
       // line (<mouse 1>+90) <mouse 2> (<mouse 1>+90) (<mouse 2>+80)
       // line <mouse 1> (<mouse 2>+80) (<mouse 1>+90) (<mouse 2>+80)
    }
    same?<key 1>100
    {
       size 100 100