Computer graphics lab assignment

1. 1
Program 1
WRITE A C PROGRAM TO DRAW LINE BY USING DDA ALGORITHM.
#include <graphics.h>
#include <stdio.h>
#include <math.h>
int main( )
{
float x,y,x1,y1,x2,y2,dx,dy,pixel;
int i,gd,gm;
printf("Enter the value of x1 : ");
scanf("%f",&x1);
printf("Enter the value of y1 : ");
scanf("%f",&y1);
printf("Enter the value of x2 : ");
scanf("%f",&x2);
printf("Enter the value of y1 : ");
scanf("%f",&y2);
detectgraph(&gd,&gm);
initgraph(&gd,&gm,"");
dx=abs(x2-x1);
dy=abs(y2-y1);
if(dx>=dy)
pixel=dx;
else
pixel=dy;
dx=dx/pixel;
dy=dy/pixel;
x=x1;
y=y1;
i=1;
while(i<=pixel)
{
putpixel(x,y,1);

2. 2
x=x+dx;
y=y+dy;
i=i+1;
delay(100);
}
getch();
closegraph();
}
OUTPUT:

3. 3
Program 2
WRITE A C PROGRAM TO DRAW LINE BY USING BRESENHAM'S ALGORITHM.
# include <stdio.h>
# include <conio.h>
# include <graphics.h>
void main()
{
int dx,dy,x,y,p,x1,y1,x2,y2;
int gd,gm;
printf("nntEnter the co-ordinates of first point : ");
scanf("%d %d",&x1,&y1);
printf("nntEnter the co-ordinates of second point : ");
scanf("%d %d",&x2,&y2);
dx = (x2 - x1);
dy = (y2 - y1);
p = 2 * (dy) - (dx);
x = x1;
y = y1;
detectgraph(&gd,&gm);
initgraph(&gd,&gm,"e:tcbgi");
putpixel(x,y,WHITE);
while(x <= x2)
{
if(p < 0)
{
x=x+1;
y=y;
p = p + 2 * (dy);
}
else
{

4. 4
x=x+1;
y=y+1;
p = p + 2 * (dy - dx);
}
putpixel(x,y,WHITE);
}
getch();
closegraph();
}
OUTPUT:

5. 5
Program 3
WRITE A C PROGRAM TO DRAW A RECTANGLE.
#include<stdio.h>
#include<graphics.h>
#include<conio.h>
int main(){
int gd = DETECT,gm;
initgraph(&gd, &gm, "C:TCBGI");
/* Draw rectangle on screen */
rectangle(150, 50, 400, 150);
/* Draw Bar on screen */
bar(150, 200, 400, 350);
getch();
closegraph();
return 0;
}
OUTPUT:

6. 6
Program 4
WRITE A C PROGRAM TO DRAW A CIRCLE.
#include<stdio.h>
#include<graphics.h>
#include<conio.h>
int main(){
int gd = DETECT,gm;
int x ,y ,radius=80;
initgraph(&gd, &gm, "C:TCBGI");
/* Initialize center of circle with center of screen */
x = getmaxx()/2;
y = getmaxy()/2;
outtextxy(x-100, 50, "CIRCLE Using Graphics in C");
/* Draw circle on screen */
circle(x, y, radius);
getch();
closegraph();
return 0;
}
OUTPUT:

7. 7
Program 5
WRITE A C PROGRAM TO DRAW A ELLIPSE.
#include<graphics.h>
#include<conio.h>
main() {
int gd = DETECT, gm;
initgraph(&gd, &gm, "C:TCBGI");
ellipse(100, 100, 0, 360, 50, 25);
getch();
closegraph();
return 0;
}
OUTPUT:

8. 8
Program 6
WRITE A C PROGRAM TO DRAW A TORUS.
#include <windows.h>
#include <GL/glut.h>
#include <stdlib.h>
static void resize(int width, int height)
{
const float ar = (float) width / (float) height;
glViewport(0, 0, width, height);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glFrustum(-ar, ar, -1.0, 1.0, 2.0, 100.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity() ;
}
static void display(void)
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glColor3d(1,0,0);
glPushMatrix();
glTranslated(0.0,1.5,-6);
glRotated(-10, 1.0, 0.0, 0.0);
glutSolidTorus(0.4, 0.8, 10, 50);
glPopMatrix();
glPushMatrix();
glTranslated(0.0,-1.2,-6);
glutWireTorus(0.4, 0.8, 10, 20);
glPopMatrix();
glutSwapBuffers();
}

9. 9
const GLfloat light_ambient[] = { 0.0f, 0.0f, 0.0f, 1.0f };
const GLfloat light_diffuse[] = { 1.0f, 1.0f, 1.0f, 1.0f };
const GLfloat light_specular[] = { 1.0f, 1.0f, 1.0f, 1.0f };
const GLfloat light_position[] = { 2.0f, 5.0f, 5.0f, 0.0f };
const GLfloat mat_ambient[] = { 0.7f, 0.7f, 0.7f, 1.0f };
const GLfloat mat_diffuse[] = { 0.8f, 0.8f, 0.8f, 1.0f };
const GLfloat mat_specular[] = { 1.0f, 1.0f, 1.0f, 1.0f };
const GLfloat high_shininess[] = { 100.0f };
/* Program entry point */
int main(int argc, char *argv[])
{
glutInit(&argc, argv);
glutInitWindowSize(640,480);
glutInitWindowPosition(10,10);
glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);
glutCreateWindow("Programming Techniques - 3D Torus");
glutReshapeFunc(resize);
glutDisplayFunc(display);
glClearColor(1,1,1,1);
glEnable(GL_CULL_FACE);
glCullFace(GL_BACK);
glEnable(GL_DEPTH_TEST);
glDepthFunc(GL_LESS);
glEnable(GL_LIGHT0);
glEnable(GL_NORMALIZE);
glEnable(GL_COLOR_MATERIAL);
glEnable(GL_LIGHTING);
glLightfv(GL_LIGHT0, GL_AMBIENT, light_ambient);
glLightfv(GL_LIGHT0, GL_DIFFUSE, light_diffuse);
glLightfv(GL_LIGHT0, GL_SPECULAR, light_specular);
glLightfv(GL_LIGHT0, GL_POSITION, light_position);
glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient);
glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);
glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);

10. 10
glMaterialfv(GL_FRONT, GL_SHININESS, high_shininess);
glutMainLoop();
return EXIT_SUCCESS;
}
OUTPUT:

11. 11
Program 7
WRITE A C PROGRAM TO SCALE AN OBJECT.
#include<stdio.h>
#include<conio.h>
#include<graphics.h>
#include<process.h>
#include<math.h>
int x1,y1,x2,y2,x3,y3,mx,my;
void draw();
void scale();
void main()
{
int gd=DETECT,gm;
int c;
initgraph(&gd,&gm," ");
printf("Enter the 1st point for the triangle:");
scanf("%d%d",&x1,&y1);
printf("Enter the 2nd point for the triangle:");
scanf("%d%d",&x2,&y2);
printf("Enter the 3rd point for the triangle:");
scanf("%d%d",&x3,&y3);
draw();
scale();
}
void draw()
{
line(x1,y1,x2,y2);
line(x2,y2,x3,y3);
line(x3,y3,x1,y1);
}
void scale()
{
int x,y,a1,a2,a3,b1,b2,b3;
int mx,my;
printf("Enter the scalling coordinates");
scanf("%d%d",&x,&y);
mx=(x1+x2+x3)/3;

12. 12
my=(y1+y2+y3)/3;
cleardevice();
a1=mx+(x1-mx)*x;
b1=my+(y1-my)*y;
a2=mx+(x2-mx)*x;
b2=my+(y2-my)*y;
a3=mx+(x3-mx)*x;
b3=my+(y3-my)*y;
line(a1,b1,a2,b2);
line(a2,b2,a3,b3);
line(a3,b3,a1,b1);
draw();
getch();
}
OUTPUT:

13. 13
Program 8
WRITE A C PROGRAM TO ROTATE AN OBJECT.
#include<stdio.h>
#include<graphics.h>
void main()
{
int gd=DETECT,gm;
int x1,y1,x2,y2 ;
float b1,b2;
float t,deg;
initgraph(&gd,&gm,”c:tc”);
printf(“Enter the coordinates of Line n”);
scanf(“%d%d%d%d”,&x1,&y1,&x2,&y2);
setcolor(6);
line(x1,y1,x2,y2);
getch();
//cleardevice();
printf(“Enter the angle of rotation: “);
scanf(“%f”,&deg);
t=(22*deg)/(180*7);
b1=abs((x2*cos(t))-(y2*sin(t)));
b2=abs((x2*sin(t))+(y2*cos(t)));
line(x1,y1,b1,b2);
getch();
closegraph();
}

14. 14
OUTPUT:
Program 9
WRITE A C PROGRAM TO SHEAR AN OBJECT ABOUT X-SHEAR, Y-SHEAR.
#include<stdio.h>
#include<conio.h>
#include<dos.h>
#include<graphics.h>
int main()
{
int poly[30],a[9][3],b[3][3],c[9][3],poly2[30];
int x=0,y=0,p,i,j,k,xc,yc,ch;
int gd=DETECT,gm;

15. 15
initgraph(&gd,&gm,"C:/TC/BGI");
xc=getmaxx()/2;
yc=getmaxy()/2;
setcolor(1);
setbkcolor(15);
setfillstyle(6,3);
printf("n Enter number of points : ");
scanf("%d",&p);
j=0;
for(i=0;i<p*2;i+=2)
{
printf("n Enter cordinate point x%d and y%d : ",j+1,j+1);
scanf("%d",&poly[i]);
scanf("%d",&poly[i+1]);
j++;
}
poly[p*2]=poly[0];
poly[p*2+1]=poly[1];
for(i=0;i<p*2;i+=2)
{
poly2[i]=xc+poly[i];
poly2[i+1]=yc-poly[i+1];
}
poly2[p*2]=poly2[0];
poly2[p*2+1]=poly2[1];
fillpoly(p+1,poly2);
line(0,yc,xc*2,yc);
line(xc,0,xc,yc*2);
printf("n Shearing of : n 1. x n 2. y n 3. Bothn enter choice : ");
scanf("%d",&ch);
if(ch==1)
{
printf("n Enter x shear value : ");
scanf("%d",&x);
}
if(ch==2)
{
printf("n Enter y shear value : ");
scanf("%d",&y);
}

16. 16
if(ch==3)
{
printf("n Enter x shear value : ");
scanf("%d",&x);
printf("n Enter y shear value : ");
scanf("%d",&y);
}
j=0;
for(i=0;i<p;i++)
{
a[i][0]=poly[j];
a[i][1]=poly[++j];
a[i][2]=1;
++j;
}
if(ch==1)
{
for(i=0;i<3;i++)
{
for(j=0;j<3;j++)
{
b[i][j]=0;
if(i==j)
{
b[i][j]=1;
}
}
}
b[1][0]=x;
}
else if(ch==2)
{
for(i=0;i<3;i++)
{
for(j=0;j<3;j++)
{
b[i][j]=0;
if(i==j)
{
b[i][j]=1;
}
}
}

17. 17
b[0][1]=y;
}
else if(ch==3)
{
for(i=0;i<3;i++)
{
for(j=0;j<3;j++)
{
b[i][j]=0;
if(i==j)
{
b[i][j]=1;
}
}
}
b[1][0]=x;
b[0][1]=y;
}
for(i=0;i<p;i++)
{
for(j=0;j<3;j++)
{
c[i][j]=0;
for(k=0;k<3;k++)
{
c[i][j]=c[i][j]+a[i][k]*b[k][j];
}
}
}
printf("nnnnnt After Shearing : ");
for(i=0,j=0;i<p;i++,j+=2)
{
poly[j] =xc+c[i][0];
poly[j+1]=yc-c[i][1];
}
poly[j] =poly[0];
poly[j+1]=poly[1];
setfillstyle(9,2);
fillpoly(p+1,poly);
getch();
closegraph();
}

18. 18
OUTPUT:
X_SHEAR:
Y-SHEAR:

19. 19
Program 10
WRITE A PROGRAM TO DEMONSTRATE REFLECTION TRANSFORMATION ABOUT X-
AXIS, Y-AXIS AND ORIGIN.
#include<stdio.h>
#include<conio.h>
#include<dos.h>
#include<graphics.h>
int main()
{
int poly[30],a[9][3],b[3][3],c[9][3],poly2[30];
int x,y,p,i,j,k,xc,yc;
int gd=DETECT,gm;
initgraph(&gd,&gm,"C:/TC/BGI");
xc=getmaxx()/2;
yc=getmaxy()/2;
setcolor(1);
setbkcolor(15);
setfillstyle(6,3);
printf("n Enter number of points : ");
scanf("%d",&p);
j=0;
for(i=0;i<p*2;i+=2)
{
printf("n Enter cordinate point x%d and y%d : ",j+1,j+1);
scanf("%d",&poly[i]);
scanf("%d",&poly[i+1]);
j++;
}
poly[p*2]=poly[0];
poly[p*2+1]=poly[1];
for(i=0;i<p*2;i+=2)
{
poly2[i]=xc+poly[i];
poly2[i+1]=yc-poly[i+1];

20. 20
}
poly2[p*2]=poly2[0];
poly2[p*2+1]=poly2[1];
fillpoly(p+1,poly2);
line(0,yc,xc*2,yc);
line(xc,0,xc,yc*2);
printf("n Reflection about : n 1. x axisn 2. y axisn 3. originn enter choice : ");
scanf("%d",&x);
j=0;
for(i=0;i<p;i++)
{
a[i][0]=poly[j];
a[i][1]=poly[++j];
a[i][2]=1;
++j;
}
if(x==1)
{
for(i=0;i<3;i++)
{
for(j=0;j<3;j++)
{
b[i][j]=0;
if(i==j)
{
b[i][j]=1;
}
}
}
b[1][1]=-1;
}
else if(x==2)
{
for(i=0;i<3;i++)
{

21. 21
for(j=0;j<3;j++)
{
b[i][j]=0;
if(i==j)
{
b[i][j]=1;
}
}
}
b[0][0]=-1;
}
else if(x==3)
{
for(i=0;i<3;i++)
{
for(j=0;j<3;j++)
{
b[i][j]=0;
if(i==j)
{
b[i][j]=-1;
}
}
}
b[2][2]=1;
}
for(i=0;i<p;i++)
{
for(j=0;j<3;j++)
{
c[i][j]=0;
for(k=0;k<3;k++)
{
c[i][j]=c[i][j]+a[i][k]*b[k][j];
}
}
}
printf("nnnnnt Reflection : ");

22. 22
for(i=0,j=0;i<p;i++,j+=2)
{
poly[j] =xc+c[i][0];
poly[j+1]=yc-c[i][1];
}
poly[j] =poly[0];
poly[j+1]=poly[1];
setfillstyle(9,2);
fillpoly(p+1,poly);
getch();
closegraph();
}
OUTPUT:
REFELCTION ABOUT ORIGIN:

23. 23
REFELCTION ABOUT X-AXIS:
REFELCTION ABOUT Y-AXIS:

24. 24