cg10

#include<iostream>
#include<graphics.h>
#include <bits/stdc++.h>
using namespace std;

class algo
{
public:
void dda_line(float x1, float y1, float x2, float y2);
void bresneham_cir(int r);
};

void algo::dda_line(float x1, float y1, float x2, float y2)
{
float x,y,dx,dy,step;
int i;
dx=abs(x2-x1);
dy=abs(y2-y1);
cout<<"dy="<<dy<<"\tdx="<<dx;
if(dx>=dy)
step=dx;
else
step=dy;
cout<<"\n"<<step<<endl;
float xinc=float((x2-x1)/step);
float yinc=float((y2-y1)/step);
x=x1;
y=y1;
i=1;
while(i<=step)
{
putpixel(320+x,240-y,4);
x=x+xinc;
y=y+yinc;
i=i+1;
}
}

void algo::bresneham_cir(int r)
{
float x,y,p;
x=0;
y=r;
p=3-(2r);
while(x<=y)
{
putpixel(320+x,240+y,1);
putpixel(320-x,240+y,2);
putpixel(320+x,240-y,3);
putpixel(320-x,240-y,5);
putpixel(320+y,240+x,6);
putpixel(320+y,240-x,7);
putpixel(320-y,240+x,8);
putpixel(320-y,240-x,9);
x=x+1;
if(p<0)
{
p=p+4(x)+6;
}
else
{
p=p+4*(x-y)+10;
y=y-1;
}
}
}

int main()
{
algo a1;
int i;
float r,ang,r1;
initwindow(630,480);
cout<<"Enter radius of circle : ";
cin>>r;
a1.bresneham_cir((int)r);
ang=3.24/180;
float c=rcos(30ang);
float s=rsin(30ang);
a1.dda_line(0,r,0-c,0-s);
a1.dda_line(0-c,0-s,0+c,0-s);
a1.dda_line(0+c,0-s,0,r);
r1=s;
a1.bresneham_cir((int)r1);
getch();
delay(20000);
return 0;
}