Computer Graphics (CG) : Write C++ program to draw the following pattern. Use DDA line and Bresenham’s circle drawing algorithm. Apply the concept of encapsulation

 

 Computer Graphics Assignment 3

Write C++ program to draw the following pattern. Use DDA line and Bresenham’s circle drawing algorithm. Apply the concept of encapsulation 

Code :

#include <iostream>

# include <graphics.h>

# include <stdlib.h>

using namespace std;

class dcircle

{

private: int x0, y0;

public:

dcircle()

{

x0=0;

y0=0;

}

void setoff(int xx, int yy)

{

x0=xx;

y0=yy;

}

void drawc(int x1, int y1, int r)

{

float d;

int x,y;

x=0;

y=r;

d=3-2*r;

do

{

putpixel(x1+x0+x, y0+y-y1, 15);

putpixel(x1+x0+y, y0+x-y1,15);

putpixel(x1+x0+y, y0-x-y1,15);

putpixel(x1+x0+x,y0-y-y1,15);

putpixel(x1+x0-x,y0-y-y1,15);

putpixel(x1+x0-y, y0-x-y1,15);

putpixel(x1+x0-y, y0+x-y1,15);

putpixel(x1+x0-x, y0+y-y1,15);

if (d<=0)

{

d = d+4*x+6;

}

else

{

d=d+4*(x-y)+10;

y=y-1;

}

x=x+1;

}

while(x<y);

}

};

class pt

{

protected: int xco, yco,color;

public:

pt()

{

xco=0,yco=0,color=15;

}

void setco(int x, int y)

{

xco=x;

yco=y;

}

void setcolor(int c)

{

color=c;

}

void draw()

{

putpixel(xco,yco,color);

}

};

class dline:public pt

{

private: int x2, y2;

public:

dline():pt()

{

x2=0;

y2=0;

}

void setline(int x, int y, int xx, int yy)

{

pt::setco(x,y);

x2=xx;

y2=yy;

}

void drawl( int colour)

{

float x,y,dx,dy,length;

int i;

pt::setcolor(colour);

dx= abs(x2-xco);

dy=abs(y2-yco);

if(dx>=dy)

{

length= dx;

}

else

{

length= dy;

}

dx=(x2-xco)/length;

dy=(y2-yco)/length;

x=xco+0.5;

y=yco+0.5;

i=1;

while(i<=length)

{

pt::setco(x,y);

pt::draw();

x=x+dx;

y=y+dy;

i=i+1;

}

pt::setco(x,y);

pt::draw();

}

};

int main()

{

int gd=DETECT, gm;

initgraph(&gd, &gm, NULL);

int x,y,r, x1, x2, y1, y2, xmax, ymax, xmid, ymid, n, i;

dcircle c;

cout<<"\nenter coordinates of centre of circle : ";

cout<<"\n enter the value of x : ";

cin>>x;

cout<<"\nenter the value of y : ";

cin>>y;

cout<<"\nenter the value of radius : ";

cin>>r;

xmax= getmaxx();

ymax=getmaxy();

xmid=xmax/2;

ymid=ymax/2;

setcolor(1);

c.setoff(xmid,ymid);

line(xmid, 0, xmid, ymax);

line(0,ymid,xmax,ymid);

setcolor(15);

c.drawc(x,y,r);

pt p1;

p1.setco(100,100);

p1.setcolor(14);

dline l;

l.setline(x1+xmid, ymid-y1, x2+xmid, ymid-y2);

cout<<"Enter Total Number of lines : ";

cin>>n;

for(i=0;i<n;i++)

{

cout<<"Enter co-ordinates of point x1 : ";

cin>>x1;

cout<<"enter coordinates of point y1 : ";

cin>>y1;

cout<<"Enter co-ordinates of point x2 : ";

cin>>x2;

cout<<"enter coordinates of point y2 : ";

cin>>y2;

l.setline(x1+xmid, ymid-y1, x2+xmid, ymid-y2);

l.drawl(15);

}

cout<<"\nEnter coordinates of centre of circle : ";

cout<<"\n Enter the value of x : ";

cin>>x;

cout<<"\nEnter the value of y : ";

cin>>y;

cout<<"\nEnter the value of radius : ";

cin>>r;

setcolor(5);

c.drawc(x,y,r);

getch();

delay(200);

closegraph();

return 0;

}

Input :

Value Of X : 100

Value Of Y : 70

Value Of R : 30

Next Inputs In Image Given Below.

Output :