Write C++/Java program to draw the following pattern using any Line drawing algorithms.

Second Year Computer Engineering Computer Graphics Programs:

Computer Graphics Lab:

Practical 8:

Write C++/Java program to draw the following pattern using any Line drawing algorithms.

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#include <stdlib.h>

#include<iostream>

#include<math.h>

#include<graphics.h>

using namespace std;

int xmax,ymax,xmid,ymid;

class DDA

{

public:

int x1,x2,y1,y2;

void line1(int x1,int y1,int x2,int y2)

{

float x,y,dx,dy,length;

int i;

dx = abs(x2-x1);

dy = abs(y2-y1);

if(dx>dy)

{length = dx;}

else

{length = dy;}

dx = (x2-x1)/length;

dy = (y2-y1)/length;

x = x1 + 0.5;

y = y1 + 0.5;

i=1;

while(i<=length)

{

putpixel(x,y,12);

x = x + dx;

y = y + dy;

i++;

}

putpixel(x,y,12);

}

};

void ddaline(int x1,int y1,int x2,int y2,int x3,int y3,int x4,int y4)

{

DDA obj;

obj.line1(x1+xmid,ymid-y1,x2+xmid,ymid-y2);

delay(300);

obj.line1(x2+xmid,ymid-y2,x3+xmid,ymid-y3);

delay(300);

obj.line1(x3+xmid,ymid-y3,x4+xmid,ymid-y4);

delay(300);

obj.line1(x4+xmid,ymid-y4,x1+xmid,ymid-y1);

delay(300);

}

int main()

{

int gd=DETECT,gm;

int x1=100,y1=50,x2=100,y2=150,x3=300,y3=150,x4=300,y4=50;

initgraph(&gd,&gm,NULL);

xmax=getmaxx();

ymax=getmaxy();

xmid=xmax/2;

ymid=ymax/2;

ddaline(x1,y1,x2,y2,x3,y3,x4,y4);

int xmid1,ymid1,xmid2,ymid2,xmid3,ymid3,xmid4,ymid4;

xmid1=(x1+x2)/2;

ymid1=(y1+y2)/2;

xmid2=(x2+x3)/2;

ymid2=(y2+y3)/2;

xmid3=(x3+x4)/2;

ymid3=(y3+y4)/2;

xmid4=(x4+x1)/2;

ymid4=(y4+y1)/2;

ddaline(xmid1,ymid1,xmid2,ymid2,xmid3,ymid3,xmid4,ymid4);

int xm1,ym1,xm2,ym2,xm3,ym3,xm4,ym4;

xm1=(xmid1+xmid2)/2;

ym1=(ymid1+ymid2)/2;

xm2=(xmid2+xmid3)/2;

ym2=(ymid2+ymid3)/2;

xm3=(xmid3+xmid4)/2;

ym3=(ymid3+ymid4)/2;

xm4=(xmid4+xmid1)/2;

ym4=(ymid4+ymid1)/2;

ddaline(xm1,ym1,xm2,ym2,xm3,ym3,xm4,ym4);

return 0;

}

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