[Interest] Replacement for Qt4 QMatrix4x4?

[Uwe Rathmann]

On Fri, 22 Feb 2019 22:27:49 +1300, Christian Gagneraud wrote:

> If you do not want to support qreal=float anymore, please do not allow
> ./configure to make that choice and maybe get rid of qreal typedef,
> and delete qreal from Qt6 API while you're at it.

Actually there are several versions of Qt5 that do not even compile when 
setting qreal=float. After reporting such a bug the fix did not even go 
into the relevant LTS version ( Qt 5.9 at that time ).

Obviously building with qreal=float seems not to be covered by the Qt 
tests and also does not seem to be seen as import by the development.

But the whole concept of qreal is questionable as it implies, that how to 
store values is always related to the hardware architecture and/or 
rendering. For a library like Qwt this is not the case and and algos like 
f.e spline interpolation suffer, when using QPointF an friends.

So yes, please remove the qreal=float option with Qt6.

Uwe