vsync(3alleg4)

💅 vsync — from the Allegro manual, section 3alleg4 ✨

okay bestie, sit down, we're talking about vsync — the little function that goes "hold up, wait for the screen to blink" 🦋. It's part of the Allegro game programming library, and yes it's pronounced however you want, it's giving whatever energy you need today.

🌸 NAME 🌸

vsync — literally just sits there and waits for a vertical retrace to begin. that's it. that's the whole job. queen of patience 👑

✨ SYNOPSIS ✨

#include <allegro.h>

void vsync();

no arguments, no return value, no drama. she takes nothing and gives you timing 🎀

💖 DESCRIPTION 💖

so like. a vertical retrace is what happens when the electron beam inside your monitor has hit the bottom of the screen and is zooming back up to the top, getting ready to do another scan. the way that it works is genuinely iconic in a retro way ngl.

during that teeny tiny window, the graphics card isn't sending any data to the monitor. which means — and this is the slay part — you can do stuff to the hardware that you literally cannot do at any other moment. the classic example: altering the palette without causing flickering (also known as snow 😭 it looks like static, it's a whole mess).

but here's the thing bestie, and I need you to hear me: Allegro already handles this for you 💫 It automatically waits for a retrace before it alters the palette or does any hardware scrolling. so like. you don't normally need to bother with this function at all. it's the backup dancer, not the main character. she's there if you want her though 🫶

👀 SEE ALSO 👀

• set_palette(3alleg4)
• scroll_screen(3alleg4)

and that's the whole page, bestie!! this was brought to you by the Allegro manual, version 4.4.3 🌈 mwah, go write something cute with it 💜✨👑