練習python的小程式

#用來練習curses
import time, curses

def draw(line,col):
  try:
    stdscr.addch(line,col,"H")
    stdscr.refresh()
    time.sleep(0.02)
  except curses.error: pass

while True:
  stdscr = curses.initscr()
  winH,winW=stdscr.getmaxyx()
  stdscr.bkgd('.')
  for Y in range (0,winH/2):
    for col in range (Y,winW-Y):
      draw(Y,col)
    for line in range (Y+1,winH-Y):
      draw(line,winW-(Y+1))
    for col in range (winW-(Y+1),Y-1,-1):
      draw(winH-(Y+1),col)
    for line in range (winH-(Y+1),Y,-1):
      draw(line,Y)
 stdscr.clear()
 curses.endwin()

如果在 text console下是正常的，但若是在 gnome-terminal
卻會在左下角出現一個"." 而不是"H" !?