// DECLARATION:

class OrientedBoundingBox : public BoundingBox
{
    public:

        mat3 rotation;

    public:

        OrientedBoundingBox( vec3 minimum, vec3 maximum, vec3 position = vec3(0.0f), mat3 rotation = mat3() ) : BoundingBox( minimum, maximum, position )
        {
            this->rotation = rotation;
        }
};

// IMPLEMENTATION #1:

BoundingVolume::TestResult Frustum::testIntersection( shared_ptr<const OrientedBoundingBox> box ) const
{
    const vec3 center = box->position+(box->maximum+box->minimum)*0.5f;
    const vec3 extents = box->position+(box->maximum-box->minimum)*0.5f;

    vec3 extentsRotated = box->rotation * extents;

    extentsRotated.x = fabsf( extentsRotated.x );
    extentsRotated.y = fabsf( extentsRotated.y );
    extentsRotated.z = fabsf( extentsRotated.z );

    for( uint i = 0; i < 6; ++i )
    {
        vec3 positiveVertex = center;
        const vec3 normal = vec3(m_planes[i]);

        positiveVertex.x += ( normal.x < 0.0f ) ? (-extentsRotated.x) : extentsRotated.x;
        positiveVertex.y += ( normal.y < 0.0f ) ? (-extentsRotated.y) : extentsRotated.y;
        positiveVertex.z += ( normal.z < 0.0f ) ? (-extentsRotated.z) : extentsRotated.z;

        if( (glm::dot(normal, positiveVertex)+m_planes[i].w) < 0.0f )
            return TEST_OUTSIDE;
    }

    return TEST_INTERSECT;
}

// IMPLEMENTATION #2:

BoundingVolume::TestResult Frustum::testIntersection( shared_ptr<const OrientedBoundingBox> box ) const
{
    const vec3 center = box->position+(box->maximum+box->minimum)*0.5f;
    const vec3 extents = box->position+(box->maximum-box->minimum)*0.5f;

    for( uint i = 0; i < 6; i++ )
    {
        const vec3 normal = vec3(m_planes[i]);

        float x = glm::dot(box->rotation[0], normal) <= 0.f ? extents.x : -extents.x;
        float y = glm::dot(box->rotation[1], normal) <= 0.f ? extents.y : -extents.y;
        float z = glm::dot(box->rotation[2], normal) <= 0.f ? extents.z : -extents.z;

        const vec3 diag = x*box->rotation[0] + y*box->rotation[1] + z*box->rotation[2];

        const vec3 nPoint = center - diag;

        if( glm::dot(nPoint, normal) + m_planes[i].w <= 0.f )
            return TEST_OUTSIDE;
    }

    return TEST_INTERSECT;
}