global gameisRunning

global birdDirection

on moveBird

   set the bottom of btn "bird" to the bottom of btn "bird" + birdDirection

   

   set the right of btn "city01" to the right of btn "city01" -4

   if the right of btn "city01" < 0 then

      set the left of btn "city01" to the right of btn "city02" -4

   end if

     set the right of btn "city02" to the right of btn "city02" -4

   if the right of btn "city02" < 0 then

      set the left of btn "city02" to the right of btn "city01" -4

   end if

   movecols

   if gameisRunning then

      send moveBird to me in 20 millisecs

   end if

end moveBird

on movecols

   repeat with i=1 to 4

      // move the top and bot columns together

      set the right of btn ("top"& i ) to the right of btn ("top"& i ) -5

      set the right of btn ("bot"& i ) to the right of btn ("bot"& i ) -5

      

      // if they go off the page

      if the right of btn ("top"& i ) < 0 then

         

         // start them again at the right side of the card 

         set the left of btn ("top"& i ) to the right of card "main" -5

         set the left of btn ("bot"& i ) to the right of card "main" -5

         

         // generate a random number between 1 and 100

         put random(100) into newloc

         

         // set the pipes to start at that new location

         set the bottom of btn ("top"& i ) to 180+newLoc

         set the top of btn ("bot"& i ) to 350+newLoc

      end if

   end repeat

   checkbird

end movecols

on checkbird

   // We do this in a loop using nymbers 1 to 4

   

   repeat with i=1 to 4

      // check bird intersect with top1, top2, top3, top4

      if intersect(btn "bird" , btn ("top"&i), 255 ) then

         endGame

      end if

      // check bird intersect with bot1, bot2, bot3, bot4

      if intersect(btn "bird" , btn ("bot"&i), 255 ) then

         endGame

      end if

   end repeat

   

end checkbird

on endGame

   answer "You crashed!"

   stopGame

end endGame

   

on startGame

   put true into gameisRunning

   put +5 into birdDirection

   moveBird

end startGame

on stopGame

   put false into gameisRunning

   set the bottom of btn "bird" to 300

end stopGame

on keyDown theKey

   if theKey is space then

      put -5 into birdDirection

   end if

end keyDown

on keyUp

   put +5 into birdDirection

end keyUp