I have been wondering if there is a possibility (or what the preferred one would be) to check if two AlignedBoxes intersect.
Using squaredExteriorDistance() works:

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AlignedBox2d boxA;
AlignedBox2d boxB;
if (boxA.squaredExteriorDistance(boxB) == 0.0)
    std::cout << "Intersection." << std::endl;


But this is rather complicated and depends on a floating point equality check.
What I am looking for is a function like contains() that simply returns a boolean. Something like:

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/** \returns true if the box \a b is intersecting the box \c *this. */
inline bool intersects(const AlignedBox& b) const
{ return (m_min.array()<=(b.max)().array()).all() && ((b.min)().array()<=m_max.array()).all(); }


Is there any such function in Eigen that I might have overlooked? What would be the easiest way to check for intersecting boxes?

Indeed, this function seems missing. In the meantime you can do:

!a.intersection(b).isEmpty()

Thank you for the answer!
Should I prepare a patch and submit it to the bug tracker as a feature request?

dsy wrote:Should I prepare a patch and submit it to the bug tracker as a feature request?

would be nice.

Any objections against making this function a free function as opposed to a member function? Or do we prefer member functions?

Regrads,
Hauke

I have created a patch and submitted it to the bug tracker as Bug 502.

Hauke wrote:Any objections against making this function a free function as opposed to a member function? Or do we prefer member functions?

I am not sure what the preferred style is, but I used the very similar contains() (member) function as a guideline.