Computer Graphics MANUAL

Computer Graphics Lab Manual

UNIVERSITY SYLLABUS FOR PRACTICALS

1. Implementation of line drawing , circle drawing & ellipse algorithm.

2. Programs to implement 2D transformation( Line , Cube , Rectangle)

Scaling Translation Rotation

3. Program to implement simple clipping algorithm. Implementation of Bezier Curve.

List Of Experiments

1. Write a program to draw the pixel(x,y) and display the color in which pixel(x,y) is illuminated on the screen.2. Write a program to implement DDA line drawing algorithm.3. Write a program to implement Bresenham’s Line drawing algorithm.4. Write a program to implement Bresenham’s Circle drawing algorithm. 5. Write a program to implement Bresenham’s Ellipse drawing algorithm.6. Write a program to implement Boundary Fill algorithm.7. Write a program to implement Flood Fill algorithm.8. Write a program to draw Rectangle from (100,200) pixel to (400,500) pixel .9. Write a program to draw a Circle with center (150,150) pixel and radius 25.10. Write a program to draw a Hexagon on the screen.11. Write a program to implement Composite Transformations.12. Write a program to implement Basic Transformations (translation ,rotation , and scaling on a rectangle).13. Write a program to implement Cohen Sutherland algorithm.14. Write a program to implement Bezier Curve.15. Write a program to implement B-Spline Curve.16. Write a program to implement animation using C function.17. Write a program to implement a cartoon using C function.18. Write a program to draw a chain of circles.19. Write a program to draw concentric circles.20. Write a program to fill an ellipse by reducing the size of an ellipse.

EXPERIMENT No. 01

AIM : Write a program to draw the pixel(x,y) and display the color in which pixel(x,y) is illuminated on the screen.

PROGRAM:

#include<stdio.h>#include<conio.h>#include<graphics.h>void main(){

int gd=DETECT,gm;initgraph(&gm,&gd,”\\tc\\bgi”);putpixel(100,200,RED);i=getpixel(100,200);printf(“The color of pixel is : “);printf(“%d”,i);getch();

}

INPUT

100,200,RED

OUTPUT.The color of pixel is : 4 (RED)

EXPERIMENT No. 02

AIM :Write a program to implement DDA line drawing algorithm.

PROGRAM

#include<stdio.h>#include<conio.h>#include<graphics.h>#include<math.h>#define Round(a) ((int) (a+0.5))

void main(){ int xa,ya,xb,yb,dx,dy,steps,k,a;

float Xincr,Yincr,X,Y;

int i,gd=DETECT,gm;

initgraph(&gd,&gm,"d:\\tc\\bgi");

printf("Enter the value of (xa , ya ) & (xb , yb)");

scanf("%d%d%d%d",&xa,&ya,&xb,&yb);

dx=xb-xa; dy=yb-ya ;

if(abs(dx)>abs(dy))

steps=abs(dx);

else

steps=abs(dy);

Xincr=(float)dx/steps;

Yincr=(float)dy/steps; X=xa;Y=yb;

putpixel(X,Y,7);

for(i=1;i<steps;i++)

{

X=X+Xincr;

Y=Y+Yincr;

putpixel(Round(X),Round(Y),7);

} getch(); closegraph();

}

INPUT

Enter the value of (xa , ya ) & (xb , yb) :- 1904225200

OUTPUT

EXPERIMENT No. 03

AIM :Write a program to implement Bresenham’s line drawing

PROGRAM

#include<stdio.h>#include<conio.h>#include<graphics.h>#include<math.h>

void main(){ int Xa,Ya,Xb,Yb;

int X,Y,dx,dy,p,Xend;

int gd=DETECT,gm;

initgraph(&gd,&gm, "d:\\tc\\bgi");

printf("Enter the value of (Xa , Ya ) & (Xb , Yb)");

scanf("%d%d%d%d",&Xa,&Ya,&Xb,&Yb);

dx=abs(Xa-Xb); dy=abs(Ya-Yb);

p=2*dy-dx;

if(Xa>Xb)

{

X=Xb;Y=Ya;

Xend=Xa;

}else

{

X=Xa;Y=Ya;

Xend=Xb;

}putpixel(X,Y,7);

while(X<Xend)

{

X++;

if(p<0)

p+=2*dy;

else

{

Y++;

p+=2*(dy-dx);

}

putpixel(X,Y,7);

}

getch();

closegraph();

}

INPUTEnter the value of (Xa , Ya ) & (Xb , Yb) :-100110240250OUTPUT

EXPERIMENT No. 04

AIM :Write a program to implement Bresenham’s Circle algorithm. PROGRAM #include<stdio.h>#include<conio.h>#include<graphics.h>

void circle_1 ( int , int ) ;

void main ( ){

int x , y , p , r , i ;

int gd=DETECT , gm ;

initgraph ( &gd , &gm , "\\tc\\bgi") ;

setbkcolor (WHITE) ;

printf ( "Enter the radius = ") ;

scanf ( "%d" , &r) ;

x = 0 ; y = r ;

p = 3 - 2 * r ;

putpixel ( x , y ,2 ) ;

while ( x <= y )

{

if (p < 0)

p+= 4 * x + 6;

else

{

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

y -- ;

}

x ++ ;

circle_1( x , y) ;

}

getch ( ) ;

closegraph ( ) ;

}void circle_1 ( int a , int b)

{

int x , y ;

x = a ; y = b ;

putpixel ( 300 + x , 300 + y , 1 ) ;

putpixel ( 300 + y , 300 + x , 1 ) ;

putpixel ( 300 - x , 300 + y , 1 ) ;

putpixel ( 300 + x , 300 - y , 1 ) ;

putpixel ( 300 - x , 300 - y , 1 ) ;

putpixel ( 300 - y , 300 - x , 1 ) ;

putpixel ( 300 + y , 300 - x , 1 ) ;

putpixel ( 300 - y , 300 + x , 1 ) ;

}

INPUTEnter the radius = 80OUTPUT

EXPERIMENT No. 05

AIM :Write a program to implement Bresenham’s ellipse algorithm.

PROGRAM

#include<stdio.h>#include<conio.h>#include<graphics.h>

void ellip(int ,int );

void main(){

int a,b;

int x=0,y;

int aa,bb,aa2,bb2;

int fx=0,fy;

int p;

int gd=DETECT,gm;

initgraph(&gd,&gm,"d:\\tc\\bgi");

printf("\n Enter the value of a and b");

scanf("%d%d",&a,&b);

y=b;aa=a*a;

bb=b*b;aa2=aa*2;

bb2=bb*2;fy=aa2*b;

p=bb-(aa*b)+(0.25*aa); setbkcolor(1);

while(fx<fy)

{

x++;

fx=fx+bb2;

if(p<0)

p+=fx+ bb;

else

{

y--;

fy=fy-aa2;

p+=fx+bb-fy;

}

x++ ;

ellip(x,y); }

getch();

closegraph();

}

void ellip(int a,int b)

{

int x,y;

x=a;y=b;

putpixel(300+x,300+y,4);

putpixel(300+y,300+x,4);

putpixel(300-x,300+y,4);

putpixel(300+x,300-y,4);

putpixel(300-x,300-y,4);

putpixel(300-y,300-x,4);

putpixel(300+y,300-x,4);

putpixel(300-y,300+x,4); }

INPUT

Enter the value of a and b =

1625

OUTPUT

EXPERIMENT No. 06

AIM :Write a program to implement Boundary fill algorithm. PROGRAM

#include<stdio.h>#include<conio.h>#include<graphics.h>

void boundary_fill(int x,int y,int fill_color,int boundary_color);

void main(){ int gd=DETECT,gm; initgraph(&gd,&gm,"D:\\tc\\bgi"); setcolor(WHITE); putpixel(310,230,RED); circle(320,240,40); boundary_fill(320,240,LIGHTGREEN,WHITE); getch();}void boundary_fill(int x,int y,int fill_color,int boundary_color){

if(getpixel(x,y)!=boundary_color && getpixel(x,y)!=fill_color) {

putpixel(x,y,fill_color);boundary_fill(x+1,y,fill_color,boundary_color);boundary_fill(x-1,y,fill_color,boundary_color);boundary_fill(x,y+1,fill_color,boundary_color);boundary_fill(x,y-1,fill_color,boundary_color);

}}

OUTPUT

EXPERIMENT No. 07

AIM :Write a program to implement Flood fill algorithm.

PROGRAM

#include<stdio.h>#include<conio.h>#include<graphics.h>

void ffill(int x,int y,int fill,int old);

void main()

{

int gd=DETECT,gm;int old=BLACK;

initgraph(&gd,&gm,"D:\\tc\\bgi");

setcolor(YELLOW);

line(310,230,330,230);setcolor(LIGHTGREEN);line(330,230,330,250);setcolor(MAGENTA);line(330,250,310,250);setcolor(CYAN);line(310,250,310,230);putpixel(321,241,GREEN);ffill(320,240,LIGHTBLUE,old);

getch();

}

void ffill(int x,int y,int fill,int old)

{

if(getpixel(x,y)==old){putpixel(x,y,fill);

ffill(x+1,y,fill,old);

ffill(x-1,y,fill,old);

ffill(x,y+1,fill,old);

ffill(x,y-1,fill,old);

ffill(x-1,y-1,fill,old);ffill(x+1,y-1,fill,old);ffill(x+1,y-1,fill,old);ffill(x-1,y+1,fill,old);

}

}

OUTPUT

EXPERIMENT No. 08

AIM :Write a program to draw Rectangle from (100,200) pixel to (400,500) pixel.

PROGRAM

#include<stdio.h>#include<conio.h>#include<stdlib.h>#include<graphics.h>main(){ int gd=DETECT,gm; initgraph(&gd,&gm,"\\tc\\bgi"); setpalette(0,3); moveto(100,200); lineto(100,400); lineto(400,400); lineto(400,200);

lineto(100,200); getch(); restorecrtmode(); return; getch(); }

OUTPUT

EXPERIMENT No. 09

AIM :Write a program to draw a Circle with center (150,150) pixel and radius 25.

DESCRIPTION: With the help of this program ,we are going to draw a Circle having a center (150,150) pixel. And radius of the circle is 25.

PROGRAM

#include<stdio.h>#include<conio.h>#include<stdlib.h>#include<graphics.h>float x1,y1,r;main(){ int gd=DETECT,gm; initgraph(&gd,&gm,"\\tc\\bgi"); printf("Enter the center 'x1','y1' and radius 'r':\n"); scanf("%f%f%f",&x1,&y1,&r); setpalette(0,12); /*background will change from 0-block to 12*/ getch(); setcolor(3); /*circle will be drawn in 3-green color*/ circle(x1,y1,r); getch(); restorecrtmode(); return;}

OUTPUT

EXPERIMENT No. 10

AIM :Write a program to draw a Hexagon on the screen.

DESCRIPTION: In this program , we are going to draw a hexagon on the screen using line(),moveto() & lineto().

PROGRAM

#include<stdio.h>#include<conio.h>#include<graphics.h>void main(){ int gd=DETECT,gm; initgraph(&gd,&gm,"c:\\tc\\bgi"); setcolor(RED); moveto(100,100); lineto(75,120); lineto(100,140); lineto(140,140); lineto(165,120); lineto(140,100); lineto(100,100); setfillstyle(SOLID_FILL,GREEN); floodfill(150,120,RED); getch();}

OUTPUT

EXPERIMENT No. 11

AIM :Write a program to implement Composite Transformation .

PROGRAM

#include <stdio.h> #include <conio.h> #include <graphics.h>

void main( )

{ int gd = DETECT , gm ;

int x1 , y1 , x4 , y4 , tx1 , ty1 , tx2 , ty2 ;

clrscr ( ) ;

initgraph (&gd , &gm ,”\\tc\\bgi”) ; rectangle ( 250 , 250 , 250 , 250 ) ;

printf ( “ Enter the End Points”) ; scanf ( “ %d %d”, &tx1 , &ty1 ) ; x1 = 250 ; x4 = 300 ;

y1 = 250 ; y4 = 300 ; x1 = x1 + tx1 ;

y1 = y1 + ty1 ;

x4 = x4 + tx1 ;

y4 = y4 + ty1 ;

rectangle ( x1 , y1 , x4 , y4 ) ;

getch ( ) ; printf ( “ Enter the value ” ) ;

scanf ( “ %d %d” , &tx2 , &ty2 ) ;

x1 = x1 + tx2 ; x4 = x4 + tx2 ;

y1 = y1 + ty2 ; y4 = y4 + ty2 ;

rectangle ( x1 , y1 , x4 , y4 ) ;

getch ( ) ;

closegraph ( ) ;

} INPUT

Enter the End Points

9080OUTPUT

INPUT

Enter the value 30 40

OUTPUT

EXPERIMENT No. 12

AIM :Write a program to implement Basic Transformations ( translation , rotation, and scaling on a Rectangle).

PROGRAM

// (A) SCALING//

# include < stdio.h > # include < conio.h > # include < graphics.h >

void main ( )

{ float t ;

int gd = DETECT , gm ;

int x1 ,y1, x4, y4, sx1, sy1 ;

initgraph ( &gd , &gm , “\\tc\\bgi” ) ;

x1 = 50 ; y1 = 50 ;

x4 = 130 ; y4 = 130 ;

rectangle ( x1, y1, x4, y4 ) ;

getch ( ) ;

cleardevice ( ) ;

printf ( “ \n Enter The Scaling Vector :” ) ; scanf ( “ %d %d ”, &sx1, &sy1 ) ;

x1 =x1 * sx1 ;

y1 = y1 * sy1 ;

x4 = x4 * sx1 ; y4 = y4 * sy1 ;

rectangle ( x1 , y1 , x4 , y4 ) ;

getch ( ) ;

closegraph ( ) ;

} OUTPUT

INPUT

Enter The Scaling Vector :- 2 3 OUTPUT

PROGRAM

// (B) TRANSLATION//

# include < stdio.h > # include < conio.h > # include < graphics.h >

void main ( )

{ float t ;

int gd = DETECT , gm ;

int x1 ,y1, x4, y4, tx1, ty1 ,ty2 ;

initgraph ( &gd , &gm , “\\tc\\bgi” ) ;

printf ( “ Enter The Four Co-ordinate For Rectangle :”) ;

scanf ( “ %d %d %d %d ” , &x1 , &y1 , &x4 , &y4 ) ;

rectangle ( x1, y1, x4, y4 ) ;

getch ( ) ;

cleardevice ( ) ;

printf ( “ \n Enter The Translation Vector :” ) ; scanf ( “ %d %d ”, &tx1, &ty1 ) ;

x1 =x1 * tx1 ;

y1 = y1 * ty1 ;

x4 = x4 * tx1 ; y4 = y4 * ty1 ;

rectangle ( x1 , y1 , x4 , y4 ) ;

getch ( ) ;

closegraph ( ) ;

}

INPUT

Enter The Four Co-ordinate For Rectangle : 50 50 100 100

OUTPUT

INPUT

Enter The Translation Vector : - 70 70

OUTPUT

PROGRAM

// (C) ROTATION//

# include < stdio.h > # include < conio.h > # include < graphics.h > # include < math.h >

void main ( )

{ float t ;

int gd = DETECT , gm ;

int x1 ,y1, x4, y4 ;

initgraph ( &gd , &gm , “\\tc\\bgi” ) ;

printf ( “ Enter Four Co-ordinates ” ) ;

scanf ( “ %d 5d %d %d ” , &x1 , &y1 , &x4 , &y4 ) ;

rectangle ( x1, y1, x4, y4 ) ;

getch ( ) ;

cleardevice ( ) ;

printf ( “ \n Enter Angle For Rotation :” ) ; scanf ( “ %f ”, &t ) ;

t = ( t * 2 * 3.14 ) / 360 ;

x1 = ( x1 * cos ( t ) + y1 * sin ( t ) ) ;

y1 = ( - x1 * sin ( t ) + y1 * cos ( t ) ) ;

x4 = ( x4 * cos ( t ) + y4 * sin ( t ) ) ; y4 = ( - x4 * sin ( t ) + y4 * cos ( t ) ) ;

rectangle ( x1 , y1 , x4 , y4 ) ;

getch ( ) ;

closegraph ( ) ;

} INPUT

Enter Four Co-ordinates : - 50 50 110 110

OUTPUT

INPUT

Enter Angle For Rotation : - 30

OUTPUT

EXPERIMENT No. 13

AIM : Write a program to implement Cohen Sutherland line Clipping

PROGRAM

#include < stdio.h> #include < conio.h> #include < graphics.h> #define ROUND ( a ) ( ( int ) ( a + 0.5 )) #define LEFT_EDGE ox1 #define RIGHT_EDGE ox2 #define BOTTOM_EDGE ox4 #define TOP_EDGE ox8

unsigned char encode ( wcpt2 pt, dept winmin, dept winmax)

{

unsigned char code = ox00 ;

if ( pt.x < winmin.x) code = code | LEFT_EDGE ;

if ( pt.x > winmax.x) code = code | RIGHT_EDGE ;

if ( pt.y < winmin.y) code = code | BOTTOM_EDGE ;

if ( pt.y > winmax.y) code = code | TOP_EDGE ;

return ( code ) ;

}

void swappts ( unsigned char *c1, unsigned char *c2)

{ unsigned char temp ;

temp = *c1 ;

*c1 = *c2 ;

*c2 = temp ;

}

void dipline ( dept winmin, dept winmax, wept2 p1, wept 2 p2)

{

unsigned char code1,code2 ;

int done = FALSE, draw = FALSE ;

float m ;

while ( ! done )

{

code1 = emode ( p1, winmin, winmax) ; code2 = emode ( p2, winmin, winmax) ;

if ( ACCEPT ( code1,code2 ))

{

done = FALSE ;

else

if ( REJECT ( code1, code2))

done = TRUE ;

else

if ( INSIDE ( code1)) { swappts ( &p1, &p2) ;

swapcodes ( &code1, &code2) ;

if ( p2.x ! = p1.x)

{

m = ( p2.y – p1.y) / ( p2.x – p1.x) ;

}

if ( code1 & LEFT_EDGE)

{

p1.y + = ( winmin.x – p1.x ) * m ;

p1.x + = winmin.x ;

}

else

if ( code & RIGHT_EDGE)

{

p1.y + = ( winmax.x – p1.x) * m ;

p1.x = winmax.x ; }

else

if ( code & BOTTOM_EDGE)

{

if ( p2.x ! = p1.x)

{

p1.x + = ( winmin.y – p1.y) / m ; p1.y = winmin.y ; }

} else

if( code & TOP_EDGE)

{

if ( p2.x ! = p1.x)

{

p1.x + = ( winmax.y – p1.y) / m ;

p1.y = winmax.y ; } }

if ( draw) lineDDA ( ROUND ( p1.x), ROUND ( p1.y), ROUND ( p2.x), ROUND ( p2.y)) ;

}

}

OUTPUT

EXPERIMENT No. 14

AIM: Write a program to implement Bezier Curve.

PROGRAM

#include < stdio.h > # include < conio.h > # include < graphicd.h > void main ( )

{ double numsteps , i , t ;

float stepsize ;

int x0 , y0 , x1 , y1 , x2 , y2 , x3 , y3 , x , y ;

int ax , ay , bx , by , cx , cy , dx , dy ;

int gd = DETECT , gm ;

initgraph ( &gd ,&gm , “ \\tc\\bgi ” ) ;

printf ( “ \n Enter The Value of x0 & y0 ” ) ; scanf ( “ %d %d ” , &x0 , &y0 ) ; printf ( “ \n Enter The Value of x1 & y1 ” ) ;

scanf ( “ %d %d ” , &x1 , &y1 ) ;

printf ( “ \n Enter The Value of x2 & y2 ” ) ; scanf ( “ %d %d ” , &x2 , &y2 ) ;

printf ( “ \n Enter The Value of x3 & y3 ” ) ;

scanf ( “ %d %d ” , &x3 , &y3 ) ;

ax = - x0 + 3 * x1 + ( - 3 * x2 ) + x3 ;

ay = - y0 + 3 * y1 + ( - 3 * y2 ) + y3 ;

bx = 3 * x0 + ( -6 * x1 ) + 3 * x2 ;

by = 3 * y0 + ( -6 * y1 ) + 3 * y2 ;

cx = 3 * x0 + 3 * x1 ;

cy = 3 * y0 + 3 * y1 ;

dx = x0 ;

dy = y0 ;

setcolor ( MAGENDA ) ;

numstep = 100 ;

stepsize = 1.0 / ( double ) numsteps ;

moveto ( dx , dy ) ;

for ( i = 1 ; i < numsteps ; i ++)

{

t = stepsize * ( double ) i ;

x = ax * ( t * t * t ) + by * ( t * t ) + cy * t + dy ;

lineto ( x , y ) ;

}

getch ( ) ;

closegraph () ; }

OUTPUT

EXPERIMENT No. 15

AIM : Write a program to implement B-Spline Curve.

PROGRAM

#include < stdio.h > #include < conio.h > #include < graphics.h >

void SplinePoint(int *u,int n,int t,double v,XYZ *control,XYZ *output) { int k; double b;

output->x = 0; output->y = 0; output->z = 0;

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

{ b = SplineBlend(k,t,u,v); output->x + = control[k].x * b; output->y + = control[k].y * b; output->z + = control[k].z * b; }

}

double SplineBlend(int k,int t,int *u,double v)

{ double value;

if (t == 1)

{ if ((u[k] <= v) && (v < u[k+1])) value = 1; else value = 0;

}

else

{ if ((u[k+t-1] == u[k]) && (u[k+t] == u[k+1])) value = 0; else if (u[k+t-1] == u[k]) value = (u[k + t] - v) / (u[k+t] - u[k+1]) * SplineBlend(k+1,t-1,u,v); else if (u[k+t] == u[k+1]) value = (v - u[k]) / (u[k+t-1] - u[k]) * SplineBlend(k,t-1,u,v); else value = (v - u[k]) / (u[k+t-1] - u[k]) * SplineBlend(k,t-1,u,v) + (u[k+t] - v) / (u[k+t] - u[k+1]) * SplineBlend(k+1,t-1,u,v);

}

return(value);

}void SplineKnots(int *u,int n,int t)

{ int j;

for (j=0;j<=n+t;j++) { if (j < t) u[j] = 0; else if (j <= n) u[j] = j - t + 1; else if (j > n) u[j] = n - t + 2; }}

OUTPUT

EXPERIMENT No. 16

AIM :Write a program to implement Animation using C function.

PROGRAM

#include < stdio.h > # include < conio.h > # include < graphicd.h > void main ( )

{ int x , y , a , b , i ;

int gd = DETECT , gm ;

initgraph ( &gd ,&gm , “ \\tc\\bgi ” ) ;

for ( i = 0 ; i < 320 ; i ++ )

{

rectangle ( 325 , 440 , 330 , 50 ) ;

rectangle ( 325 , 440 , 440 , 455 ) ;

rectangle ( 325 , 440 - i , 450 , 370 - i ) ;

circle ( 387 , 410 – i , 10 ) ;

line ( 325 , 399 – i , 450 , 399 – i ) ;

line ( 325 , 420 – i , 450 , 420 – i ) ;

delay ( 15 ) ;

clear device ( ) ;

}

rectangle ( 325 , 410 , 330 , 50 ) ;

rectangle ( 325 , 440 , 440 , 455 ) ;

rectangle ( 325 , 120 , 450 , 50 ) ;

circle ( 387 , 90 , 10 ) ;

line ( 325 , 79 , 450 , 79 ) ;

line ( 325 , 100 , 450 , 100 ) ;

outtextxy ( x , y , “ * ” ) ;

getch ( ) ; closegraph ( ) ; } }

OUTPUT

EXPERIMENT No. 17

AIM :Write a program to implement a cartoon using C function.

PROGRAM

#include<stdio.h>#include<conio.h>#include<graphics.h>#include<dos.h>

void main()

{

int gd = DETECT , gm, i, a ;

clrscr( ) ;

initgraph ( &gd, &gm, "c:\\tc\\bgi") ;

for (i = (- 80 ) ; i< = 300 ; i + = 5 )

{

circle ( 200 + i, 200,100 ) ;

setfillstyle(SOLID_FILL,i) ;

floodfill ( 200 + i, 200, WHITE ) ;

circle ( 160 + i, 160, 10 ) ;

setfillstyle ( SOLID_FILL, i + 1 ) ;

floodfill (160 + i, 160, WHITE ) ;

circle ( 240 + i, 160, 10 ) ;

setfillstyle ( SOLID_FILL, i + 1 ) ;

floodfill ( 240 + i, 160, WHITE ) ;

arc (200 + i, 200, 200, 340, 60 ) ;

delay ( 200 ) ;

clrscr( ) ; }

getch( ) ;

}

OUTPUT

EXPERIMENT No. 18

AIM :Write a program to draw a chain of Circle.

PROGRAM

# include<graphics.h># include<conio.h># include<stdio.h>#include<math.h>void main(){

int gd = DETECT, gm , i ;

initgraph ( &gd, &gm, "c:\\tc\\bgi") ;

for(i=50;i<200;i=i+30){

circle(i,i+30,50);getch();restorcrtmode();

}

OUTPUT

EXPERIMENT No. 19

AIM :Write a program to display concentric circles.

PROGRAM

#include<stdio.h>#include<conio.h>#include<graphics.h>void main(){int gd=DETECT,gm;initgraph(&d,&m,"c:\\tc\\bgi");setcolor(4);for(i=50;i<150;i+=50){

circle(150,150,i);getch();/*draw concentric circle of radius i pixels and center at 50,50,I in color 3*/restorcrtmode();

}

OUTPUT

EXPERIMENT No. 20

AIM :Write a program to fill an ellipse by reduce the size of ellipse.

PROGRAM

#include<graphics.h>include<stdio.h>#include<conio.h>#include<math.h>elli_R(xc,yc,rx,ry)float xc,yc,rx,ry;{

while(rx>0.0 && ry>0.0){

ellipse(xc,yc,0,360,rx,ry);--rx;++ry;getch();

}return;

}

void main(){

float xc,yc,rx,ry;int gd=DETECT,gm,i;initgraph(&gd,&gm,”c:\\tc\\bgi”);setpalette(0,23);for(i=0;i<=7;++i){

setcolor(1);getch();ellipse(250,250,0,360,140,80);getch();elli_R(250.0,250.0,140.0,80.0);

}restorecrtmode();return;}

OUTPUT