I want to rotate a line around a point. The code that follows does
this, BUT when it draws a line, it leaves next to the line its ghost.
Is this a problem with pygame, or is there a change I can make in the
code which will make the problem go away?
import pygame, sys
from pygame.locals import *
import time
pygame.init()
#create a surface that will be seen by the user
screen =Â pygame.display.set_mode((400, 400))
#create a varible for degrees pf rotation
degree = 0
while True:
  for event in pygame.event.get():
    # quit the game if escape is pressed
    if event.type == QUIT:
      sys.exit()
    elif event.type == KEYDOWN and\
        event.key == K_ESCAPE:
      sys.exit()
  #clear screen at the start of every frame
  screen.fill((40, 40, 40))
  #create new surface with white BG
  surf = pygame.Surface((1000, 5))
  surf.fill((255, 255, 255))
  #set a color key for blitting
  surf.set_colorkey((255, 0, 0))
  ##ORIGINAL UNCHANGED
  #where will the static image be placed:
  where = (0,200)
  #draw surf to screen and catch the rect that blit returns
  blittedRect = screen.blit(surf, where)
  ##ROTATED
  #get center of surf for later
  oldCenter = blittedRect.center
  #rotate surf by DEGREE amount degrees
  rotatedSurf = pygame.transform.rotate(surf, degree)
  #get the rect of the rotated surf and set it's center to the oldCenter
  rotRect = rotatedSurf.get_rect()
  rotRect.center = oldCenter
  #draw rotatedSurf with the corrected rect so it gets put in the proper spot
  screen.blit(rotatedSurf, rotRect)
  #change the degree of rotation
  degree += 5
  if degree > 360:
    degree = 0
  #show the screen surface
  pygame.display.flip()
  #wait 60 ms until loop restart
  pygame.time.wait(60)