1bitmap_mask_color(3) Allegro manual bitmap_mask_color(3)
2
3
4
6 bitmap_mask_color - Returns the mask color of the specified bitmap.
7 Allegro game programming library.
8
10 #include <allegro.h>
11
12
13 int bitmap_mask_color(BITMAP *bmp);
14
16 Returns the mask color for the specified bitmap (the value which is
17 skipped when drawing sprites). For 256-color bitmaps this is zero, and
18 for truecolor bitmaps it is bright pink (maximum red and blue, zero
19 green). A frequent use of this function is to clear a bitmap with the
20 mask color so you can later use this bitmap with masked_blit() or
21 draw_sprite() after drawing other stuff on it. Example:
22
23 /* Replace mask color with another color. */
24 for (y = 0; y h; y++)
25 for (x = 0; x w; x++)
26 if (getpixel(bmp, x, y) == bitmap_mask_color(bmp))
27 putpixel(bmp, x, y, another_color);
28
29
31 MASK_COLOR_8(3), set_color_depth(3), bitmap_color_depth(3), ex3d(3),
32 exmouse(3), expat(3)
33
34
35
36Allegro version 4.4.2 bitmap_mask_color(3)