starBounce

local star = {5,5}
term.redirect(peripheral.wrap("right"))
local w,h = term.getSize()
local dir = "++"

dir = dir:sub(1,1)..dir:sub(2,2)

function Main()
  redraw(star[1],star[2])
  local posX,posY = term.getCursorPos()
  if posX == 1 then
    dir = "+"..dir:sub(2,2)
  elseif posX == w then
    dir = "-"..dir:sub(2,2)
  end
  if posY == 1 then
    dir = dir:sub(1,1).."+"
  elseif posY == h then
    dir = dir:sub(1,1).."-"
  end
  local modX = dir:sub(1,1)
  local modY = dir:sub(2,2)
  if modX == "+" then
    star[1] = star[1] + 1
  else
    star[1] = star[1] - 1
  end
  if modY == "+" then
    star[2] = star[2] + 1
  else
    star[2] = star[2] - 1
  end
end


function redraw(x,y)
  draw("*",x,y)
  sleep(.5)
  draw(" ",x,y)
end

function draw(words,x,y)
  term.setCursorPos(x,y)
  write(words)
end

while true do
  Main()
end