man do_ellipse () - Calculates all the points in an ellipse. Allegro game programming library.
NAME
do_ellipse - Calculates all the points in an ellipse. Allegro game programming library.
SYNOPSIS
#include <allegro.h>
void do_ellipse(BITMAP *bmp, int x, int y, int rx, ry, int d, void (*proc)(BITMAP *bmp, int x, int y, int d));
DESCRIPTION
Calculates all the points in an ellipse around point (x, y) with radius rx and ry, calling the supplied function for each one. This will be passed a copy of the bmp parameter, the x and y position, and a copy of the d parameter, so it is suitable for use with putpixel(). Example:
void draw_explosion_ring(BITMAP *bmp, int x, int y, int d)
{
...
}
do_ellipse(screen, SCREEN_W/2, SCREEN_H/2,
SCREEN_H/16, SCREEN_H/32, flame_color,
draw_explosion_ring);