Palette sort (on brightness) now uses a better formula, provided by DawnBringer. Text tool no longer crashes with some fonts. Added support for bitmap fonts from 'Bitmap Font Writer', such as those from http://www.zone38.net/font/bmpfont.html or http://www.matriaxweb.com/others.htm or http://www.genvid.com/moonstruck/downloads/fonts.html

git-svn-id: svn://pulkomandy.tk/GrafX2/trunk@1530 416bcca6-2ee7-4201-b75f-2eb2f807beb1

src/op_c.c

@@ -165,6 +165,16 @@ void HSL_to_RGB(byte h,byte s,byte l, byte* r, byte* g, byte* b)
     *b = bf * (255);
 }
 
+///
+/// Returns a value that is high when color is near white,
+/// and low when it's darker. Used for sorting.
+long Perceptual_lightness(T_Components *color)
+{
+  return 26*color->R*26*color->R +
+         55*color->G*55*color->G +
+         19*color->B*19*color->B;
+}
+
 // Conversion table handlers
 // The conversion table is built after a run of the median cut algorithm and is
 // used to find the best color index for a given (RGB) color. GIMP avoids