utils_math.py 文件源码

def normal3points(a, b, c):
    """Retorna el vector normal dado tres puntos a, b, c"""
    if isinstance(a, types.ListType) or isinstance(a, types.TupleType):
        a = Vector3(*a)
        b = Vector3(*b)
        c = Vector3(*c)
    elif isinstance(a, Point3):
        a = Vector3(*a.export_to_list())
        b = Vector3(*b.export_to_list())
        c = Vector3(*c.export_to_list())
    cross_result = (a - c).cross(b - c).get_normalized()
    if cross_result.get_x() == -0.0:
        cross_result.set_x(0.0)
    if cross_result.get_y() == -0.0:
        cross_result.set_y(0.0)
    if cross_result.get_z() == -0.0:
        cross_result.set_z(0.0)
    return cross_result