I am attempting to write a simple program to move a image across a tile background. I got it working by making everything it's own class, but it was too much typing. I read and reread the moveit program and the docs for it and tried to splice it into my own. I get either a background and no player or i get a background with an error:

Traceback (most recent call last):
File "F:\PYGA\backgroundworks.pyw", line 78, in ?
if __name__ == '__main__': main()
File "F:\PYGA\backgroundworks.pyw", line 75, in main
heros.draw(screen)
File "D:\PROGRA~1\PYTHON~1.2\Lib\site-packages\pygame\sprite.py", line 459, in draw
surface_blit(s.image, s.rect)
TypeError: invalid destination position for blit

Here's the program.

import os, sys
import pygame
from pygame.locals import *

global playerpos
playerpos = 2

#Taken from moveit.py, using it because it works
def load_image(name):
path = os.path.join('data', name)
return pygame.image.load(path).convert()

#my player class
class Player(pygame.sprite.Sprite):
def __init__(self):
pygame.sprite.Sprite.__init__(self)
self.image = self.rect = load_image('player.bmp')
screen = pygame.display.get_surface()
self.area = screen.get_rect()
self.playerpos = 2
playerpos = self.playerpos
#self.playerpos = 2
self.topleft = 0 * 32, 0

def update(self):
self.topleft = 0 * 32, 0

def left(self):
if self.playerpos >= 1:
self.playerpos = self.playerpos - 1
self.update()

def right(self):
if self.playerpos <= 2:
self.playerpos = self.playerpos + 1
self.update()

def main():
pygame.init()
screen = pygame.display.set_mode((4 * 32, 32))
pygame.display.set_caption('Hero')
#My images to load for background
Terr1 = load_image('terr1.bmp')
Terr2 = load_image('terr2.bmp')
Terr3 = load_image('terr3.bmp')
#Create an array for the background, easy loading
background = [Terr1, Terr2, Terr3]
for i in range(3):
screen.blit(background[i], (i*32, 0))

pygame.display.flip()

clock = pygame.time.Clock()
hero = Player()
heros = pygame.sprite.RenderPlain((hero))
pygame.display.flip()


while 1:
clock.tick(60)
#event sequence
for event in pygame.event.get():

if event.type == QUIT: #quit prog
return
elif event.type == KEYDOWN and event.key == K_ESCAPE: #quit prog
return
elif event.type == KEYDOWN and event.key == K_LEFT:
hero.left()
elif event.type == KEYDOWN and event.key == K_RIGHT:
hero.right()

hero.update()
screen.blit(background[playerpos], (playerpos*32,0))
heros.draw(screen)
pygame.display.flip()

if __name__ == '__main__': main()

Thanks for the help,
Jarin Scott

I removed the Player class and everything that dealt with it and was able to get the background. I slowly added the Player class and ran the program with no errors, and then added the heor.update() and heros.draw(screen) after blitting the screen. I get the following error:
Traceback (most recent call last):
File "D:\WINDOWS.000\Desktop\pygame short\background_w_player.py", line 71, in ?
if __name__ == '__main__': main()
File "D:\WINDOWS.000\Desktop\pygame short\background_w_player.py", line 67, in main
hero.update()
File "D:\PROGRA~1\PYTHON~1.2\Lib\site-packages\pygame\sprite.py", line 323, in update
s.update()
File "D:\WINDOWS.000\Desktop\pygame short\background_w_player.py", line 28, in update
self.rect.topleft = 32, 0
TypeError: 'Surface' object has only read-only attributes (assign to .topleft)

Removing the hero.update() gives me the error posted in my first post. One more thing, I am using whitespace it just wasn't posted.

Jarin Scott

Does anyone have any idea about what is wrong with the above. If it will help I can post the orignal program that works but it is long (about 114 lines). If you know any sites to visit for information it would be appreicated. I read the tutorial sfor pugame and python and am understanding the stuff but I need to use them to grasp them hence this program. It may not be much but it's a start to learning something new and different.

Jarin Scott

Howdy,

Don't know the answer to your question, but this is a good place that I've gotten help with my fledgling python programs:

Comp.lang.python

It takes a while to see your post, and for the replies to come in, but the literal experts on the language post there frequently, and there's plenty of help to be found.

I haven't done anything serious with classes yet, or with graphics, so sorry I'm not much help. Hopefully, that link will help, though.


Python Language Website also has plenty of links for "newbies" such as us.

hth.

Thanks for the reply. I got the program working but I still have no idea why it doesn't work. I added another def to load images using a short form of the orignal format and used it to load the background.

Jarin Scott