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[pygame] blit anomalies in pygame 1.8.1release



Two (unrelated) anomalies in pygame.Surface.blit(), bugs or what ?

Tests in windows XP + sp2
Python 2.4.3 (#69, Mar 29 2006, 17:35:34) [MSC v.1310 32 bit (Intel)] on win32
pygame 1.8.1release ( installed from pygame-1.8.1release.win32-py2.4.msi )

1. The pygame documentation and help(pygame.Surface.blit) tells
Surface.blit(source, dest, area=None, special_flags = 0): return Rect

but
surf.blit(sf2,(0,0),special_flags = op)

crashes with traceback:
[...]
  File "F:\newcode\_minitest\pygame blit\eblit.py", line 23, in blend
    surf.blit(sf2,(0,0),special_flags = op) # crash
TypeError: blit() takes no keyword arguments

Replacing with:
surf.blit(sf2,(0,0),None,op)
there is no crash.

On the other side, dst1.blit(src1, (0,0)) is acceptable.

Looks like a bug or that the real signature is
Surface.blit(source, dest, *args ): return Rect ?


( eblit.py demoes this problem )

 

2. When blitting (with no blend flags) an opaque pixel ( alpha channel at 255 ) over any other pixel, seems natural that the resulting color be the src color. (opaque is opaque, right ?). In most cases pygame is off by one, by example:
.   dst is filled with (x,0,0,128)
.   src is filled with (0,z,0,255)
.   dst.blit(src,(0,0)) will be filled with ( 0, z-1, 0, 255)    

( minusblit.py demoes this )

--
claxo