man putpixel () - Writes a pixel into a bitmap. Allegro game programming library.
NAME
putpixel - Writes a pixel into a bitmap. Allegro game programming library.
SYNOPSIS
#include <allegro.h>
void putpixel(BITMAP *bmp, int x, int y, int color);
DESCRIPTION
Writes a pixel to the specified position in the bitmap, using the current drawing mode and the bitmap's clipping rectangle. Example:
putpixel(screen, 10, 30, some_color);