Re: [pygame] BUG: Mask.overlap

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)]:

Â Â Âprint(prev - y, end=', ')

Â Â Âprev = 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.jones@xxxxxxxxx> 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 <siebenhundertzehn@xxxxxxxxx> 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

Re: [pygame] BUG: Mask.overlap_mask