Python: some pygame objects do not appear -

i'm building game have dodge bricks on road. blocks appear little white lines in center of window (the lane separators blocks can move) won't , crashes game when load up!

this code:

import pygame import time import random  pygame.init()              #colour acronym chart #|  black = blck  |  grey = gry   | dark = drk    | white = wht #|  deep = dp     |  metal = mtl  | light = lht   | cyan = cyn #|  blue = bl     |  baby = bby   | maroon = mrn  | #|  red = rd      |  fire = fr    | orange = orng |  # window colour index wht = (255, 255, 255) blck = (0, 0, 0)             dp_gry = (32, 32, 32)        mtl_gry = (96, 96, 96)     lht_gry = (160, 160, 160)  dp_bl = (0, 0, 102) lht_bby_bl = (0, 128, 255) cyn = (0, 153, 153)  drk_mrn = (102, 0, 0) fr_rd = (255, 0, 0) lht_orng = (255, 128, 0) #end of colour module  display_width = 800 display_height = 600    gamedisplay = pygame.display.set_mode((display_width,display_height)) pygame.display.set_caption('hard drive') clock = pygame.time.clock()  bg = pygame.image.load("asphalt.jpg")   carimg = pygame.image.load('car1.png') car_width = 45 car_height = 45  def things(thingx, thingy, thingw, thingh, color):     pygame.draw.rect(gamedisplay, color, [thingx, thingy, thingw, thingh])  def middle_road(roadx, roady, roadw, roadh, color):     pygame.draw.rect(gamedisplay, color, [roadx, roady, roadw, roadh])  def car(x,y):     gamedisplay.blit(carimg,(x,y))  def text_objects(text, font):     textsurface = font.render(text, true, blck)     return textsurface, textsurface.get_rect()  def message_display(text):     largetext = pygame.font.font('freesansbold.ttf',115)     textsurf, textrect = text_objects(text, largetext)     textrect.center = ((display_width/2),(display_height/2))     gamedisplay.blit(textsurf, textrect)      pygame.display.update()      time.sleep(2)      game_loop()    def crash():     message_display('you crashed')  def game_loop():     x = (display_width * 0.45)     y = (display_height * 0.8)      x_change = 0     thing_starty = -600     thing_speed = 7     thing_width = 100     thing_height = 100      middle_road_starty = display_height     middle_road_speed = 7     middle_road_width = 50     middle_road_height = 75     middle_road_startx = (0, display_width/2)      thing_startx = random.randrange(0, display_width)      gameexit = false      while not gameexit:          event in pygame.event.get():             if event.type == pygame.quit:                 pygame.quit()                 quit()              if event.type == pygame.keydown:                 if event.key == pygame.k_left:                     x_change = -5                 if event.key == pygame.k_right:                     x_change = 5              if event.type == pygame.keyup:                 if event.key == pygame.k_left or event.key == pygame.k_right:                     x_change = 0          x += x_change          gamedisplay.fill(wht)          #inside of game loop         gamedisplay.blit(bg, (0, 0))          #thingx, thingy, thingw, thingh, color         things(thing_startx, thing_starty, thing_width, thing_height, cyn)         thing_starty += thing_speed          car(x,y)         middle_road(middle_road_startx, middle_road_starty, middle_road_width, middle_road_height, wht)         middle_road_starty += middle_road_speed          if x > display_width - car_width or x < 0:             crash()          if thing_starty > display_height:             thing_starty = 0 - thing_height             thing_startx = random.randrange(0, display_width)          if y < thing_starty+thing_height:             print('y crossover')              if x > thing_startx , x < thing_startx + thing_width or x + car_width > thing_startx , x + car_width < thing_startx + thing_width:                 print('x crossover')                 crash()           pygame.display.update()         clock.tick(60)  game_loop() pygame.quit() quit() 

now here error:

python 3.2.1 (default, jul 10 2011, 21:51:15) [msc v.1500 32 bit (intel)] on win32 type "copyright", "credits" or "license()" more information. >>> ================================ restart ================================ >>>  traceback (most recent call last):   file "c:\users\aidan\desktop\pygame\frame.py", line 144, in <module>     game_loop()   file "c:\users\aidan\desktop\pygame\frame.py", line 123, in game_loop     middle_road(middle_road_startx, middle_road_starty, middle_road_width, middle_road_height, wht)   file "c:\users\aidan\desktop\pygame\frame.py", line 48, in middle_road     pygame.draw.rect(gamedisplay, color, [roadx, roady, roadw, roadh]) typeerror: rect argument invalid >>> ================================ restart ================================ >>>  

why rect not valid? if works "thing" object, why cant work "middle_road" object? missing something?

your problem middle_road_startx tuple , not int:

middle_road_startx = (0, display_width/2) 

looking @ rest of code guess want:

middle_road_startx = random.randrange(0, display_width/2) 

edit

however not part of question, in comments express want object in middle of screen, replace these lines:

middle_road_starty = display_height middle_road_speed = 7 # if want static in middle why have speed? middle_road_width = 50 middle_road_height = 75 middle_road_startx = (0, display_width/2) 

with:

middle_road_speed = 7 # if want static in middle why have speed? middle_road_width = 50 middle_road_height = 75 middle_road_startx = (display_width/2) - (middle_road_width/2) middle_road_starty = (display_height/2) - (middle_road_height/2) 

so first calculate middle of screen (display_width/2),(display_height/2) , offset width/height of object wanna draw there (middle_road_width/2),(middle_road_height/2)