BBox.cpp

// Vectormath https://github.com/erwincoumans/sce_vectormath
class Ray
{
public:
    Ray();
public:
    Vectormath::Aos::Vector3 m_pos;
    Vectormath::Aos::Vector3 m_dir;
    Vectormath::Aos::Vector3 m_invDir; // 1.0f / m_dir per elem
    float m_min;
    float m_max;
};

bool BBox::Intersect(const Ray &ray) const
{
    using namespace Vectormath;
    Aos::Vector3 t1(Aos::mulPerElem(m_min - ray.m_pos, ray.m_invDir));
    Aos::Vector3 t2(Aos::mulPerElem(m_max - ray.m_pos, ray.m_invDir));

    Aos::Vector3 tmin1(Aos::minPerElem(t1, t2));
    Aos::Vector3 tmax1(Aos::maxPerElem(t1, t2));

    float tmin = Aos::maxElem(tmin1);
    float tmax = Aos::minElem(tmax1);

    return tmax >= std::max(ray.m_min, tmin) && tmin < ray.m_max;
}