polygon.cpp
double magCross(vec2 v1, vec2 v2, vec2 v3) {
	double v = ((v2.x()-v1.x())*(v3.y()-v2.y()) - (v3.x()-v2.x())*(v2.y()-v1.y()));
	//cout << "v1: " << v1 << " v2: " << v2 << " v3: " << v3 <<  " mag: " << v << endl;
	return v;
}
/* helper cross on 3 verts - create vector and cross */
helper cross on 3 verts - create vector and cross
helper cross on 3 verts - create vector and cross
double magCross(vec2 v1, vec2 v2, vec2 v3) {
	double v = ((v2.x()-v1.x())*(v3.y()-v2.y()) - (v3.x()-v2.x())*(v2.y()-v1.y()));
	return v;
}
double magCross ( vec2 v1 , vec2 v2 , vec2 v3 ) { double v = ( ( v2 . x ( ) - v1 . x ( ) ) * ( v3 . y ( ) - v2 . y ( ) ) - ( v3 . x ( ) - v2 . x ( ) ) * ( v2 . y ( ) - v1 . y ( ) ) ) ; return v ; }
helper cross on 3 verts - create vector and cross
helper cross on 3 verts - create vector and cross
//cout << "v1: " << v1 << " v2: " << v2 << " v3: " << v3 <<  " mag: " << v << endl;