/usr/include/python2.7/pygame/bitmask.h is in python-pygame 1.9.1release+dfsg-5.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 | /*
Bitmask 1.7 - A pixel-perfect collision detection library.
Copyright (C) 2002-2005 Ulf Ekstrom except for the bitcount
function which is copyright (C) Donald W. Gillies, 1992.
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef BITMASK_H
#define BITMASK_H
#ifdef __cplusplus
extern "C" {
#endif
#include <limits.h>
/* Define INLINE for different compilers. If your compiler does not
support inlining then there might be a performance hit in
bitmask_overlap_area().
*/
#ifndef INLINE
# ifdef __GNUC__
# define INLINE inline
# else
# ifdef _MSC_VER
# define INLINE __inline
# else
# define INLINE
# endif
# endif
#endif
#define BITMASK_W unsigned long int
#define BITMASK_W_LEN (sizeof(BITMASK_W)*CHAR_BIT)
#define BITMASK_W_MASK (BITMASK_W_LEN - 1)
#define BITMASK_N(n) ((BITMASK_W)1 << (n))
typedef struct bitmask
{
int w,h;
BITMASK_W bits[1];
} bitmask_t;
/* Creates a bitmask of width w and height h, where
w and h must both be greater than 0.
The mask is automatically cleared when created.
*/
bitmask_t *bitmask_create(int w, int h);
/* Frees all the memory allocated by bitmask_create for m. */
void bitmask_free(bitmask_t *m);
/* Clears all bits in the mask */
void bitmask_clear(bitmask_t *m);
/* Sets all bits in the mask */
void bitmask_fill(bitmask_t *m);
/* Flips all bits in the mask */
void bitmask_invert(bitmask_t *m);
/* Counts the bits in the mask */
unsigned int bitmask_count(bitmask_t *m);
/* Returns nonzero if the bit at (x,y) is set. Coordinates start at
(0,0) */
static INLINE int bitmask_getbit(const bitmask_t *m, int x, int y)
{
return (m->bits[x/BITMASK_W_LEN*m->h + y] & BITMASK_N(x & BITMASK_W_MASK)) != 0;
}
/* Sets the bit at (x,y) */
static INLINE void bitmask_setbit(bitmask_t *m, int x, int y)
{
m->bits[x/BITMASK_W_LEN*m->h + y] |= BITMASK_N(x & BITMASK_W_MASK);
}
/* Clears the bit at (x,y) */
static INLINE void bitmask_clearbit(bitmask_t *m, int x, int y)
{
m->bits[x/BITMASK_W_LEN*m->h + y] &= ~BITMASK_N(x & BITMASK_W_MASK);
}
/* Returns nonzero if the masks overlap with the given offset.
The overlap tests uses the following offsets (which may be negative):
+----+----------..
|A | yoffset
| +-+----------..
+--|B
|xoffset
| |
: :
*/
int bitmask_overlap(const bitmask_t *a, const bitmask_t *b, int xoffset, int yoffset);
/* Like bitmask_overlap(), but will also give a point of intersection.
x and y are given in the coordinates of mask a, and are untouched
if there is no overlap. */
int bitmask_overlap_pos(const bitmask_t *a, const bitmask_t *b,
int xoffset, int yoffset, int *x, int *y);
/* Returns the number of overlapping 'pixels' */
int bitmask_overlap_area(const bitmask_t *a, const bitmask_t *b, int xoffset, int yoffset);
/* Fills a mask with the overlap of two other masks. A bitwise AND. */
void bitmask_overlap_mask (const bitmask_t *a, const bitmask_t *b, bitmask_t *c, int xoffset, int yoffset);
/* Draws mask b onto mask a (bitwise OR). Can be used to compose large
(game background?) mask from several submasks, which may speed up
the testing. */
void bitmask_draw(bitmask_t *a, const bitmask_t *b, int xoffset, int yoffset);
void bitmask_erase(bitmask_t *a, const bitmask_t *b, int xoffset, int yoffset);
/* Return a new scaled bitmask, with dimensions w*h. The quality of the
scaling may not be perfect for all circumstances, but it should
be reasonable. If either w or h is 0 a clear 1x1 mask is returned. */
bitmask_t *bitmask_scale(const bitmask_t *m, int w, int h);
/* Convolve b into a, drawing the output into o, shifted by offset. If offset
* is 0, then the (x,y) bit will be set if and only if
* bitmask_overlap(a, b, x - b->w - 1, y - b->h - 1) returns true.
*
* Modifies bits o[xoffset ... xoffset + a->w + b->w - 1)
* [yoffset ... yoffset + a->h + b->h - 1). */
void bitmask_convolve(const bitmask_t *a, const bitmask_t *b, bitmask_t *o, int xoffset, int yoffset);
#ifdef __cplusplus
} /* End of extern "C" { */
#endif
#endif
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