//
// Computergraphik II
// Prof. Dr. Juergen Doellner
// Wintersemester 2001/02
// 
// Rahmenprogramm zu Aufgabenzettel 1
//

#include "triangle.h"
#include <iostream.h>
#include <assert.h>
#include <algorithm>

Triangle::Triangle() { }

Triangle::Triangle(const Vector& v0,const Vector& v1, const Vector& v2) {
    v_[0] = v0; 
    v_[1] = v1; 
    v_[2] = v2;
    triNrm_ = makeCWTriangleNormal(v_[0],v_[1],v_[2]);
    n_[0] = n_[1] = n_[2] = triNrm_;
}


void Triangle::normalizeNormals() {
    n_[0].normalize();
    n_[1].normalize();
    n_[2].normalize();
}

//
// IO
//



istream& operator>>(istream& s, Triangle& u) {    
    Vector t0, t1, t2;
    // for (int i = 0; i < 3; i++) {
        if (!(s >> t0[0] >> t0[1] >> t0[2] >> t1[0] >> t1[1] >> t1[2] >> t2[0] >> t2[1] >> t2[2]) ) {
            assert(0);
        }
        u.v_[0] = t0;
        u.v_[1] = t1;
        u.v_[2] = t2;
    //}            
    u.triNrm_ = makeCWTriangleNormal(u.v_[0],u.v_[1],u.v_[2]);
    u.n_[0] = u.n_[1] = u.n_[2] = u.triNrm_;
    return s;
}