The position of the surface shouldn't matter for a mask, though.
The value is curious. It also works with a positive offset. Perhaps these
will give some clues as to what's happening:
print [m1.overlap_mask(m2, (x, x)).count() for x in range(50)]
[10000, 9702, 9408, 9118, 8832, 8550, 8272, 7998, 7728, 7462, 7200, 6942,
6688, 6438, 6192, 5950, 5712, 5478, 5248, 5022, 4800, 4582, 4368, 4158,
3952, 3750, 3552, 3358, 3168, 2982, 2800, 2622, 2448, 2278, 2112, 1950,
1792, 1701, 1612, 1525, 1440, 1357, 1276, 1197, 1120, 1045, 972, 901, 832,
765]
prev = 10000
for y in [m1.overlap_mask(m2, (x, x)).count() for x in range(50)]:
print(prev - y, end=', ')
prev = y
0, 298, 294, 290, 286, 282, 278, 274, 270, 266, 262, 258, 254, 250, 246,
242, 238, 234, 230, 226, 222, 218, 214, 210, 206, 202, 198, 194, 190, 186,
182, 178, 174, 170, 166, 162, 158, 91, 89, 87, 85, 83, 81, 79, 77, 75, 73,
71, 69, 67,
You can file a bug at the link below, I couldn't find any existing issues
mentioning overlap_mask with a quick search.
https://bitbucket.org/pygame/pygame/issues
Russell
On 5 July 2014 21:26, Russell Jones <russell.jo...@gmail.com> wrote:
> Might it be that one method assumes a position of (0,0) if none is set,
> and the other does not? Is the result consistent for the unexpected result?
> If not, that would suggest the values have not been initialised.
>
> Russell
>
>
> On 19 June 2014 16:14, Florian Krause <siebenhundertz...@gmail.com> wrote:
>
>> Hello together,
>>
>> Mask.overlap_mask does not what it is supposed to do. In the following
>> example, the two counts that are output should be the same. The second one
>> is the one from overlap_mask. I have no clue what goes wrong there, since
>> the results does not make any sense to me.
>>
>> Please let me know how I can get the correct overlap mask in the case
>> below.
>>
>> Thanks,
>> Florian
>>
>>
>>
>> import pygame
>>
>> pygame.init()
>> pygame.display.init()
>> pygame.display.set_mode((800, 600))
>> s1 = pygame.Surface((100, 100)).convert_alpha()
>> s2 = pygame.Surface((200, 200)).convert_alpha()
>> s1.fill((0,0,0))
>> s2.fill((0,0,0))
>>
>> m1 = pygame.mask.from_surface(s1)
>> m2 = pygame.mask.from_surface(s2)
>>
>> print m1.overlap_area(m2, (-150, 50))
>> print m1.overlap_mask(m2, (-150, 50)).count()
>>
>>
>>
>>
>> --
>> www.fladd.de - Homepage of Florian Krause
>>
>
>
