CG Ass 4 - Transformation

#include <iostream>
#include <graphics.h>
#include <cmath>
#include <string>
using namespace std;

class Transform {
public:
    int m, a[20][20], c[20][20];
    int i, j, k;
public:
    void object();
    void accept();

    void operator * (float b[20][20]){
        for (i = 0; i < m; i++){
            for (j = 0; j < m; j++) {
                c[i][j] = 0;
                for (k = 0; k < m; k++) {
                    c[i][j] += (a[i][k] * b[k][j]);
                }
            }
        }
    }
};

void Transform::object(){
    int gd, gm;
    gd = DETECT;
    initgraph(&gd, &gm, nullptr);
    line(300, 0, 300, 600);
    line(0, 300, 600, 300);

    for (i = 0; i < m - 1; i++){
        line (300 + a[i][0], 300 - a[i][1], 300 + a[i + 1][0], 300 - a[i + 1][1]);
    }
    line (300 + a[0][0], 300 - a[0][1], 300 + a[i][0], 300 - a[i][1]);

    for (i = 0; i < m - 1; i++){
        line (300 + c[i][0], 300 - c[i][1], 300 + c[i + 1][0], 300 - c[i + 1][1]);
    }
    line (300 + c[0][0], 300 - c[0][1], 300 + c[i][0], 300 - c[i][1]);

    int temp;
    cout << "Press 1 to continue: " << endl;
    cin >> temp;
    closegraph();
}

void Transform::accept() {
    cout << "\n";
    cout << "Enter the number of edges: ";
    cin >> m;
    cout << "\nEnter the Coordinates: ";
    for (i = 0; i < m; i++){
        for (j = 0; j < 3; j++){
            if (j >= 2) a[i][j] = 1;
            else cin >> a[i][j];
        }
    }
}

int main() {
    int ch, tx, ty, sx, sy;
    float deg, theta, b[20][20];
    Transform t;
    t.accept();

    cout << "----- MENU -----" << endl;
    cout << "1. Translation\n2. Scaling\n3. Rotation" << endl;
    cout << "Enter your Choice: "; cin >> ch;
    switch (ch) {
        case 1:
            cout << "Translation Operation" << endl;
            cout << "Enter values for tx and ty: "; cin >> tx >> ty;
            b[0][0] = b[2][2] = b[1][1] = 1;
            b[0][1] = b[0][2] = b[1][0] = b[1][2] = 0;
            b[2][0] = tx;
            b[2][1] = ty;
            t * b;
            t.object();
            break;

        case 2:
            cout << "Scaling Operation" << endl;
            cout << "Enter value for sx and sy: "; cin >> sx >> sy;
            b[0][0] = sx;
            b[1][1] = sy;
            b[0][1] = b[0][2] = b[1][0] = b[1][2] = 0;
            b[2][0]= b[2][1] = 0;
            b[2][2] = 1;
            t * b;
            t.object();
            break;

        case 3:
            cout << "Rotation Operation" << endl;
            cout << "Enter value for the angle: "; cin >> deg;
            theta = deg * (3.14/100);
            b[0][0] = b[1][1] = cos(theta);
            b[0][1] = sin(theta);
            b[1][0] = sin(-theta);
            b[0][2] = b[1][2] = b[2][0] = b[2][1] = 0;
            b[2][2] = 1;
            t * b;
            t.object();
            break;

        default:
            cout << "ERROR! Please Enter a valid choice " << endl;
    }

    getch();

    return 0;
}