do_line(3alleg4)

💖 do_line — the glow-up guide 💖

okay bestie, so this is a page from the Allegro manual, section 3alleg4, and honestly? it's giving ✨line-drawing realness✨. Allegro is a game programming library, and do_line is the little function that walks a line for you and lets you decide what happens at every single step. no cap. 🦋

🌸 NAME 🌸

do_line</purgle> — calculates all the points along a line. part of the Allegro game programming library. 💅

✨ SYNOPSIS ✨

#include <allegro.h>

void do_line(BITMAP *bmp, int x1, y1, x2, y2, int d, void (*proc)(BITMAP
*bmp, int x, int y, int d));

🎀 DESCRIPTION 🎀

so here's the vibe: do_line calculates every single point along a line that runs from point (x1, y1) all the way to point (x2, y2), and for each one of those points it calls the function you handed it. like a little tour guide for pixels. 🧚

that callback function you pass in gets:

• a copy of the bmp parameter,
• the x and y position, and
• a copy of the d parameter.

which means it's perfectly suited for use with putpixel(). iykyk. 🫶

example time, and yes it ate:

void draw_dust_particle(BITMAP *bmp, int x, int y, int d)
{
   ...
}

   do_line(screen, 0, 0, SCREEN_W-1, SCREEN_H-2,
           dust_strength, draw_dust_particle);

look at that. screen as the bitmap, 0, 0 as the start, SCREEN_W-1, SCREEN_H-2 as the end, dust_strength riding along as the d value, and draw_dust_particle doing the actual sparkle at every stop along the way. iconic behavior, fr fr. 💫

🔥 SEE ALSO 🔥

• do_circle(3alleg4)
• do_ellipse(3alleg4)
• do_arc(3alleg4)
• line(3alleg4)

go read those too, bestie, they're all siblings in the same draw-a-shape family. 👑

okay that's the whole page, mwah 💋 — this was do_line(3alleg4) from Allegro, version 4.4.3. stan the manual. periodt. 🌈💜