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al_grab_font_from_bitmap(3)                        al_grab_font_from_bitmap(3)

NAME
       al_grab_font_from_bitmap - Allegro 5 API

SYNOPSIS

              #include <allegro5/allegro_font.h>

              ALLEGRO_FONT *al_grab_font_from_bitmap(ALLEGRO_BITMAP *bmp,
                 int ranges_n, const int ranges[])

DESCRIPTION
       Creates a new font from an Allegro bitmap.  You can delete the bitmap
       after the function returns as the font will contain a copy for itself.

       Parameters:

       o bmp: The bitmap with the glyphs drawn onto it

       o n: Number of unicode ranges in the bitmap.

       o ranges: 'n' pairs of first and last unicode point to map glyphs to
         for each range.

       The bitmap format is as in the following example, which contains three
       glyphs for 1, 2 and 3.

              .............
              . 1 .222.333.
              . 1 .  2.  3.
              . 1 .222.333.
              . 1 .2  .  3.
              . 1 .222.333.
              .............

       In the above illustration, the dot is for pixels having the background
       color.  It is determined by the color of the top left pixel in the
       bitmap.  There should be a border of at least 1 pixel with this color
       to the bitmap edge and between all glyphs.

       Each glyph is inside a rectangle of pixels not containing the
       background color.  The height of all glyph rectangles should be the
       same, but the width can vary.

       The placement of the rectangles does not matter, except that glyphs are
       scanned from left to right and top to bottom to match them to the
       specified unicode codepoints.

       The glyphs will simply be drawn using al_draw_bitmap(3), so usually you
       will want the rectangles filled with full transparency and the glyphs
       drawn in opaque white.

       Examples:

              int ranges[] = {32, 126};
              al_grab_font_from_bitmap(bitmap, 1, ranges)

              int ranges[] = {
                  0x0020, 0x007F,  /* ASCII */
                  0x00A1, 0x00FF,  /* Latin 1 */
                  0x0100, 0x017F,  /* Extended-A */
                  0x20AC, 0x20AC}; /* Euro */
              al_grab_font_from_bitmap(bitmap, 4, ranges)

       The first example will grab glyphs for the 95 standard printable ASCII
       characters, beginning with the space character (32) and ending with the
       tilde character (126).  The second example will map the first 96 glyphs
       found in the bitmap to ASCII range, the next 95 glyphs to Latin 1, the
       next 128 glyphs to Extended-A, and the last glyph to the Euro
       character.  (This is just the characters found in the Allegro 4 font.)

SEE ALSO
       al_load_bitmap(3), al_grab_font_from_bitmap(3)

Allegro reference manual                           al_grab_font_from_bitmap(3)