MatrixTransform.cpp~

#include<iostream>
#include<graphics.h>
#include<math.h>

using namespace std;
void disp(int n, float c[][3])
{
    float maxx, maxy;
    int i;
    maxx= getmaxx();
    maxy= getmaxy();
    maxx/=2;
    maxy/=2;
    i=0;
    while(i<n-1)
    {
        line(maxx+c[i][0], maxy-c[i][1], maxx+c[i+1][0], maxy-c[i+1][1]);
        i++;
    }
    i=n-1;
    line(maxx+c[i][0], maxy-c[i][1], maxx+c[0][0], maxy-c[0][1]);
    setcolor(15);
    line(0, maxy, maxx*2,maxy);
    line(maxx,0,maxx,maxy*2);
    setcolor(WHITE);
}
void mul(int n, float b[][3], float c[][3], float a[][3])
{
    int i,j,k;
    for(i=0;i<n;i++)
        for(j=0;j<3;j++)
        {
            a[i][j]=0;
    }
    for(i=0;i<n;i++)
    for(j=0;j<3;j++)
     for(k=0;k<3;k++)
     {
            a[i][j]+=c[i][k]*b[k][j];
    }
}
void translation(int n, float c[][3], float tx, float ty)
{
    int i;
    for(i=0;i<n;i++)
    {
        c[i][0] = c[i][0]+tx;
        c[i][1]=c[i][1]+ty;
    }
}
void scaling(int n, float c[][3], float sx, float sy)
{
    float b[10][3], a[10][3];
    int i=0,j;
    for(i=0;i<3;i++)
        for(j=0;j<3;j++)
            b[i][j]=0;
    b[0][0]=sx;
    b[1][1]=sy;
    b[2][2]=1;
    mul(n,b,c,a);
    setcolor(BLUE);
    disp(n,a);
}
void rotation(int n, float c[][3], float ra)
{
    int i=0,j;
    float b[10][3], xp, yp, a[10][3];
    xp = c[0][0];
    yp = c[0][1];
    for(i=0;i<3;i++)
        for(j=0;j<3;j++)
            b[i][j]=0;
    b[0][0]=cos(ra*3.14/180);
    b[1][1]=cos(ra*3.14/180);
    b[0][1]=sin(ra*3.14/180);
    b[1][0]=-sin(ra*3.14/180);
    b[2][0] = (-xp*cos(ra*3.14/180))+(yp*sin(ra*3.14/180))+xp;
    b[2][1]= (-xp*sin(ra*3.14/180))-(yp*cos(ra*3.14/180))+yp;
    b[2][2]=1;
    mul(n,b,c,a);
    setcolor(WHITE);
    disp(n,a);
}
int main()
{
        int i,j,k,cho,n,gd=DETECT,gm;
        float c[10][3],tx,ty,sx,sy,ra;
        initgraph(&gd,&gm,"");
        printf("Enter number of vertices\n");
        scanf("%d",&n);
        for(i=0;i<n;i++)
        {
            printf("Enter coordinates of %d vertex \n",i+1);
            scanf("%f%f",&c[i][0],&c[i][1]);
            c[i][2]=1;
        }
        do
        {
            printf("\n1.Translation\n2.Scaling\n3.Rotation\n");
            scanf("%d",&cho);
            switch(cho)
            {
                case 1: printf("Enter factor\n");
                        scanf("%f%f",&tx,&ty);
                        setcolor(BLUE);
                        disp(n,c);
                        translation(n,c,tx,ty);
                        disp(n,c);
                        getch();
                        break;
                case 2: printf("Enter factor\n");
                        scanf("%f%f",&sx,&sy);
                        setcolor(BLUE);
                        disp(n,c);
                        scaling(n,c,sx,sy);
                        disp(n,c);
                        getch();
                        break; 
                case 3: printf("Enter angle\n");
                        scanf("%f",&ra);
                        setcolor(BLUE);
                        disp(n,c);
                        rotation(n,c,ra);
                        disp(n,c);
                        getch();
                default : break;
            }
        }
        while(cho!=4);
        getch();
	int in = 0;

while (in == 0) {
    in = getchar();
}
        closegraph();
        return 0;
}