[Development] Changing qreal to a float

andre.poenitz at nokia.com andre.poenitz at nokia.com
Mon Feb 20 19:42:06 CET 2012

Abecasis Joao wrote:
> What's the porting effort for applications that use and depend on qreal?

The effort depends mainly on whether there will be a way to have a "double" 
incarnation of the "coordinate classes".

_If_ there is a *D set (e.g. the proposed thin wrapper around a *Base<T>
then the porting effort would be limited. I'd even call it "acceptable".

If there is _no_ way to use the coordinate class with doubles the 
effort will be significant as the applications would essentially have to
create the *D classes themselves, or find a substitute outside Qt.
Implementing e.g. QPolygon::intersected() on your own is no fun.

> The bigger porting effort doesn't come from the disappearance of qreal 
> itselft, but from changing Qt itself to not use it as users will no longer
> be able to assume QRectF and whatnot use double on their platform. 
> And no one seems to be against that.

I am not sure I parse that correctly. But to re-iterate: The main problem is
is the disappearance of the "double" instances, no matter how they are called.


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