//returns area( triangle(a, b ,c) ) float area(const fvec &a, const fvec &b, const fvec &c) { float area = doubleArea(a, b, c); area /= 2.0; return area; }
int Polygon::area() const { Q_D(const Polygon); if (d->m_area < 0) { d->m_area = doubleArea(d->m_points); } return d->m_area; }