# Bresenhams Circle Drawing Algorithm in c++ language programming

Using outtextxy and putpixel function in graphics function it will draw the Breshenhams circle drawing algorithm. Putpixel and outtextxy they two have the three arguments using these argument it will draw the circle

#include<iostream.h>
#include<graphics.h>
#include<conio.h>
#include<math.h>
#include<dos.h>
#include<stdlib.h>
#include<stdio.h>
class mycircle
{
private:
int x,y,r,d,x1,y1;
public:
mycircle();
void showcircle();
}
mycircle::mycircle()
{
x=0,y=0;
cout<<"Enter the Co-ordinates of Circle:";
cin>>x>>y;
cout<<"Enter the Radius of the Circle:";
cin>>r;
}
void mycircle::showcircle()
{
char *s;
x1=0,y1=r;
d=3-2*r;
while(x1<=y1)
{
putpixel((x+x1+320),(y+y1+240),5);
putpixel((x-x1+320),(y+y1+240),5);
putpixel((x+x1+320),(y-y1+240),5);
putpixel((x-x1+320),(y-y1+240),5);
putpixel((x+y1+320),(y+x1+240),5);
putpixel((x-y1+320),(y+x1+240),5);
putpixel((x+y1+320),(y-x1+240),5);
putpixel((x-y1+320),(y-x1+240),5);
if(d<0)
{
d+=4*x1+6;
}
else
{
d+=4*(x1-y1)+10;
y1--;
}
x1++;
}
setcolor(5);
outtextxy(318+x,235+y," ");
setcolor(15);
sprintf(s,"Center(%d,%d)",x,y);
outtextxy(20,10,"The Center is at:");
outtextxy(20,20,s);
outtextxy(20,30,s);
getch();
}
void main()
{
int gd=DETECT,gm,i,j,xx=190,xxx=480;
clrscr();
mycircle a;
char *mess[]={"b","r","e","s","e","n","h","a","m","s","c","i","r","c","l","e","a","l","g",
"o","r","i","t","h","m"};
initgraph(&gd,&gm,"C:/tc/bgi");
cleardevice();
rectangle(120,40,320,240);
rectangle(320,40,520,240);
rectangle(120,240,320,440);
rectangle(320,240,520,440);
for(i=0,j=27;i<16,j<=14;i++,j--)
{
xx+=10;
outtextxy(xx,10,mess[i]);
xxx-=10;
outtextxy(xxx,10,mess[j]);
delay(100);
}
for(i=130;i<=510;i+=10)
for(j=50;j<=430;j+=10)
putpixel(i,j,15);
for(i=130;i<510;i+=10)
{
if(i==320)
{
continue;
}
outtextxy(i,237,"+");
}
for(i=50;i<=430;i+=10)
{
if(i==240)
{
continue;
}
outtextxy(317,i,"-");
}
outtextxy(310,230,"o");
outtextxy(530,240,"x");
outtextxy(320,450,"-y");
outtextxy(100,240,"-x");
outtextxy(320,30,"y");
a.showcircle();
closegraph();
}
Output for Bresenhams Circle Drawing Algorithm CS1355-Graphics and Multimedia Lab