Programs using 2­D transformations­ Translations, rotation, scaling.reflection, shear using homogeneous matrix representation.

#include<stdio.h>

#include<conio.h>

#include<graphics.h>

#include<dos.h>

#include<math.h>

#include<stdlib.h>

void menu();

void input();

void output();

void translation();

void rotation();

void scaling();

void shearing();

void reflection();

int gd,gm;

int a[10][2],i,x,option,temp,angle,tx,ty,fx,fy,sh,k,n,axis,y;

float sx,sy;

void menu()

{

printf("menu\n");

printf("1.Translation\n");

printf("2.rotation\n");

printf("3.scaling\n");

printf("4.shearing\n");

printf("5.reflection\n");

printf("6.exit\n");

printf("enter the choice:");

scanf("%d",&option);

switch(option)

                                                {

case  1:

input();

translation();

break;

case 2:

input();

rotation();

break;

case 3:

input();

scaling();

break;

case 4 :

input();

shearing();

break;

case 5:

input();

reflection();

break;

case 6:

exit(0);

break;

                                       }

}

void input()

{

printf("enter the number of vertices:" );

scanf("%d",&n);

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

                                                {

printf("enter the coordinates:");

scanf("%d%d%d%d",&a[i][0],&a[i][1],&a[i+1][0],&a[i+1][1]);

                                       }

}

void output()

{

cleardevice();

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

                                       {

                                                                   line(a[i][0],a[i][1],a[i+1][0],a[i+1][1]);

                                                }

}

void translation()

{

output();

printf("enter the tranformation vertex tx,ty:\n");

scanf("%d%d",&tx,&ty);

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

                                                {

a[i][0]=a[i][0]+tx;

a[i][1]=a[i][1]+ty;

                                                }

output();

delay(10);

menu();

}

void rotation()

{

output();

printf("enter the rotating angle:");

scanf("%d",&y);

printf("enter the pivot point:");

scanf("%d%d",&fx,&fy);

                                                k=(y*3.14)/180;

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

                                                {

                                                                    a[i][0]=fx+(a[i][0]-fx)*cos(k)-(a[i][1]-fy)*sin(k);

                                                                    a[i][1]=fy+(a[i][0]-fx)*sin(k)-(a[i][1]-fy)*cos(k);

                                                }

output();

delay(10);

menu();

}

void scaling()

{

output();

printf("enter the scaling factor\n");

scanf("%f%f",&sx,&sy);

printf("enter the fixed point:");

scanf("%d%d",&fx,&fy);

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

                                                {

a[i][0]=a[i][0]*sx+fy*(1-sx);

a[i][1]=a[i][1]*sy+fy*(1-sy);

                                                }

output();

delay(10);

menu();

}

void shearing()

{

output();

printf("enter the shear value:");

scanf("%d",&sh);

printf("enter the fixed point:");

scanf("%d%d",&fx,&fy);

printf("enter the axis for shearing if x-axis then 1 if y-axis the 0:");

scanf("%d",&axis);

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

                                                {

if(axis==1)

                                                                    {

a[i][0]=a[i][0]+sh*(a[i][1]-fy);

                                                                    }

else

                                                                    {

a[i][1]=a[i][1]+sh*(a[i][0]-fx);

                                                                    }

                                                }

output();

delay(10);

menu();

}

void reflection()

{

output();

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

                                                {

temp=a[i][0];

a[i][0]=a[i][1];

a[i][1]=temp;

                                                }

output();

delay(10);

menu();

}

void main()

{

detectgraph(&gd,&gm);

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

menu();           getch();   

}