Hiya!
I've been experiencing some segfaults when using Surface.fill(), and I
think I've tracked it down to occur when you use blend modes (so one of
the surface_fill_blend_*-functions in surface_fill.c is probably to
blame?) and you fill an area of a surface that's out of bounds on the
surface. (E.g. fill a 50x50 area of a 10x10 surface)
Example code to reproduce is attached. I'm using pygame from the Ubuntu
python-pygame package in intrepid (version: 1.8.1release-0ubuntu1).
Let me know if something is unclear, or this isn't reproducible on your
system. :)
--
Kindest regards, Jørgen P. Tjernø
#!/usr/bin/python
# Code that reproduces problems with Surface.fill() & blend-modes, when
# fill-rect is out-of-bounds for the destination surface.
# (c) Jørgen P. Tjernø, 2008. ([EMAIL PROTECTED])
#
# Start it with python reproduce.py, first scene should be "ok" (show a faded
# red square in the upper left), press space to go to next scene, this is broken.
# Application might crash, or it'll crash when you press space (and pygame.quit
# is called).
import pygame
screen = pygame.display.set_mode((100, 100), pygame.DOUBLEBUF | pygame.HWSURFACE)
surf = pygame.surface.Surface((50, 50)).convert_alpha()
c = (255, 80, 80, 64)
bg = pygame.Color('black')
def nextScene():
for event in pygame.event.get():
if hasattr(event, 'key') and event.type == pygame.KEYDOWN:
if event.key == pygame.K_SPACE:
return True
return False
clock = pygame.time.Clock()
while not nextScene():
clock.tick(10)
screen.fill(bg)
# Invalid fill; rect > surf.
# Works fine, clamps to the surf size.
surf.fill(c, (0, 0, 100, 100))
screen.blit(surf, (0, 0))
pygame.display.flip()
while not nextScene():
clock.tick(10)
screen.fill(bg)
# Invalid fill; rect > surf.
# Totally borks. In my app - segfaults at fill,
# in this test, when you press space and quit I get a double free error.
# Something funky is going on with memory, an overflow?
surf.fill(c, (0, 0, 100, 100), pygame.BLEND_RGBA_ADD)
screen.blit(surf, (0, 0))
pygame.display.flip()
pygame.quit()
