al_fixadd(3)

✨ NAME ✨

okay so this is al_fixadd(3) from the Library Functions Manual, and it’s the Allegro 5 API entry for al_fixadd — bestie, that’s the whole vibe 💅.

🦋 SYNOPSIS 🦋

#include <allegro5/allegro.h>

al_fixed al_fixadd(al_fixed x, al_fixed y);

💖 DESCRIPTION 💖

So like, fixed point numbers can totally be added with the normal + integer operator, but that gives you zero protection against overflow. No cap. If overflow is a problem for you, you should use this function instead. It is slower than using integer operators, but if an overflow occurs it will set Allegro’s errno and clamp the result, rather than just letting it wrap. Iconic behavior, honestly 🫶.

Example:

al_fixed result;

/* This will put 5035 into `result'. */
result = al_fixadd(al_itofix(5000), al_itofix(35));

/* Sets errno and puts -32768 into `result'. */
result = al_fixadd(al_itofix(-31000), al_itofix(-3000));
assert(!al_get_errno()); /* This will fail. */

🌸 RETURN VALUE 🌸

Returns the clamped result of adding x to y, and sets Allegro’s errno to ERANGE if there was an overflow. Slay ✨.

🎀 SEE ALSO 🎀

• al_fixsub(3)
• al_fixmul(3)
• al_fixdiv(3)

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And that’s the whole page, bestie — source/version situation is the Allegro reference manual for al_fixadd(3), and the footer gives no date, so I’m literally not inventing one, periodt 🫶💜.