/* ************************************************************************** */
/*                                                                            */
/*  ML_circle.c                                                               */
/*  | Project : monochromelib                                                 */
/*                                                                            */
/*  By: Pierre "PierrotLL" Le Gall <legallpierre89@gmail.com>                 */
/*  Last updated: 2011/11/22                                                  */
/*                                                                            */
/* ************************************************************************** */

#include <monochrome/internals.h>

void ML_circle(int x, int y, int radius, ML_Color color)
{
	int plot_x, plot_y, d;

	if(radius < 0) return;
	plot_x = 0;
	plot_y = radius;
	d = 1 - radius;

	ML_pixel(x, y+plot_y, color);
	if(radius)
	{
		ML_pixel(x, y-plot_y, color);
		ML_pixel(x+plot_y, y, color);
		ML_pixel(x-plot_y, y, color);
	}
	while(plot_y > plot_x)
	{
		if(d < 0)
			d += 2*plot_x+3;
		else
		{
			d += 2*(plot_x-plot_y)+5;
			plot_y--;
		}
		plot_x++;
		if(plot_y >= plot_x)
		{
			ML_pixel(x+plot_x, y+plot_y, color);
			ML_pixel(x-plot_x, y+plot_y, color);
			ML_pixel(x+plot_x, y-plot_y, color);
			ML_pixel(x-plot_x, y-plot_y, color);
		}
		if(plot_y > plot_x)
		{
			ML_pixel(x+plot_y, y+plot_x, color);
			ML_pixel(x-plot_y, y+plot_x, color);
			ML_pixel(x+plot_y, y-plot_x, color);
			ML_pixel(x-plot_y, y-plot_x, color);
		}
	}
}