[Interest] Centering camera on bounding volume change in Qt3D

[Maxime Roussin-Bélanger]

On Sun, Mar 26, 2023 at 3:35 AM Mike Krus <mike.krus at kdab.com> wrote:
>
> But doesn’t the system know you are changing the entities?
> You say mouse click changes the entities, what does it do exactly, are you using a QObjectPicker or something?


No QObjectPicker, well maybe in the future, but at the moment we are
only using menus, but I was curious how to find
the whole bounding volume of the scene, but I think we can simplify it.

Imagine instead of the whole scene we have `Qt3DCore::QGeometry`; on
this object, we have
{min,max}ExtentChanged. Instead, I would like to listen to the
bounding volume changed signal instead of being double-tapped by
those two signals. I found https://bugreports.qt.io/browse/QTBUG-54584
which would be helpful for something
we are trying to do.

If we can get the entity bounding sphere changed signal I don't think
I would need it on the scene.\

Max.


>
> Mike
>
>
> > On 26 Mar 2023, at 07:38, Maxime Roussin-Bélanger <maxime.roussinbelanger at gmail.com> wrote:
> >
> > On Sat, Mar 25, 2023 at 11:55 AM Mike Krus <mike.krus at kdab.com> wrote:
> >>
> >>
> >>
> >>> On 25 Mar 2023, at 15:04, Maxime Roussin-Bélanger <maxime.roussinbelanger at gmail.com> wrote:
> >>>
> >>> Hello,
> >>>
> >>> The entity change is caused by user input, the user moves the mouse over the entity and changes its shape, or it can use
> >>> a menu to change the entity shape. I think I would have to inject the camera into _every_ entity object?
> >> If the user moves the mouse, something in your application must be changing the shape, that can also reset the camera…
> >> I think I need example code of what you are trying to achieve.
> >>
> >
> > I don't want my entities to know about the camera, ideally, I would
> > like the system, qt, to tell me that the bounding sphere has changed
> > in some ways.
> >
> > Max.
> >
> >>
> >> Mike
> >>
>
> —
> Mike Krus | mike.krus at kdab.com | Senior Software Engineer & Teamlead
> KDAB (UK) Ltd., a KDAB Group company
> Tel: UK Office +44 1625 809908   Mobile +44 7833 491941
> KDAB - The Qt Experts, C++, OpenGL Experts
>