[AD] text_nlength()

[varobert@xxxxxxxxxx (GodOfWar)]

Here I submit this code.
I find that quite useful espescially in the GUI's text manipulation routines.

I'm also working on a multiline text input GUI object, hope it can be included in Allegro.

- GodOfWar


/* text_nlength:
 *  Calculates the length of the first num characters
 *  of a string in a particular font.
 */
int text_nlength(FONT *f, char *str, int num)
{
   FONT *range;
   int c, len, g;

   len = 0;
   g = 0;

   while (((c = ugetx(&str)) != 0) && (g < num)) {
      range = find_range(f, c);

      if (!range)
	 range = find_range(f, (c = '^'));

      if (range) {
	 c -= range->start;

	 if (range->widthhook)
	    len += range->widthhook(range->glyphs, c);
	 else if (range->mono)
	    len += ((FONT_GLYPH *)(range->glyphs[c]))->w;
	 else
	    len += ((BITMAP *)(range->glyphs[c]))->w;
      }
      g++;
   }

   return len;
}