[Development] Move math3d from QtGui to QtCore

[Laszlo Papp]

> I didn't say anything about there being an outside library. I'm simply saying
> that, as the QtCore maintainer, I do not want those classes in QtCore. The
> only thing I said about "other modules" is "please check Eigen first".

Like I said, we have used that about two years ago when I first took a
look at that, and not feasible for my project from what I can say. See
the previous emails about that.

> And I'd like not to have the model classes in QtCore when I'm making a
> networking application, but we live in an imperfect world. If we divide the
> libraries too much, we lose in load time because the dynamic linker will
> suffer. Instead, we try to provide a reasonable set of libraries by
> compromising a little.

We have discussed that, if you cannot accept this in QtCore, it does
not mean the collaboration cannot happen outside QtGui somewhere else.

> So QVector2D is *definitely* on-topic.

Yes, side effect, so not the highest project for me. However, yes, I
was proposing the collaboration about the whole math3d module though.

> Then these classes that are in QtGui need to stay in QtGui unmodified. We
> settle the subject: there's nothing to be moved. Anything you may want to add
> is a new feature and would be something for 5.1. I'd like to see it born as a
> playground project first.

That is a sad consequence to me, because:

1) If Qt5.0 does not move this around, we can probably forget this for
Qt5 to be eliminated
2) I would rather prefer to move first, and then add new features.

If it really cannot happen, I might have a local copy in my project. :(

Best Regards,
Laszlo Papp