adding trimmed pygame from SVN

1 files changed, 138 insertions, 0 deletions

diff --git a/pygame/bitmask.h b/pygame/bitmask.h
new file mode 100755
index 0000000..9e4dcbf
--- /dev/null
+++ b/pygame/bitmask.h
@@ -0,0 +1,138 @@
+/*
+    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);
+
+#ifdef __cplusplus
+} /* End of extern "C" { */
+#endif
+
+#endif