Re: [Plplot-devel] Tentative plan for removing our support of Qt4

[Alan W. I. <Ala...@gm...>]

On 2019-09-07 16:46+0930 Jonathan Woithe wrote:

> Hi Alan
>
> On Mon, Sep 02, 2019 at 01:36:30PM -0700, Alan W. Irwin wrote:
>> As someone here with a large familiarity with Qt, I would appreciate
>> you letting me know if you forsee any trouble with this overall plan
>> to remove our Qt4 support.  And comments on this plan from the other
>> PLplot developers here are also encouraged.
>
> Depending on the timing between the versions which make up the plan, I
> suspect this will be fine.  FYI Slackware does not (yet) ship Qt5 (there are
> various reasons for this, the discussion of which is outside the scope of
> this thread).  There is a third-party source of Qt5 for Slackware though
> which users can install if they have a need for Qt5.
>
> Therefore once PlPlot 5.18.0 rolls around, plplot will no longer be usable
> under a standard Slackware installation unless the Qt5 packages from the
> AlienBob repository are installed.  The other option (which I'm personally
> *really* hoping for) is that Qt5 ships in Slackware by that time.  If this
> happens, the yet to be released Slackware 15 will be the first Slackware
> version to ship Qt5 as part of the distribution.
>
> Given the low number of users of plplot on Slackware I don't believe your
> plan should be changed as a result of the above information, especially
> since there is a viable workaround.  I mention it only for completeness so
> people are aware of the possible impact and the steps needed to circumvent
> it.

Hi Jonathan:

Thanks for this information about the current lack of Qt5 on official
Slackware.  My gut feeling is Qt4 has become dated and Qt5 is its
worthy successor.  Therefore, I would be surprised if this lack of Qt5
on Slackware persists much longer, i.e., I think it is likely you will
get your wish sooner rather than later.

But if that doesn't happen for some reason, PLplot-5.18.0 would still
be usable on official Slackware if a user decided not to use the
workaround you mentioned above.  Of course, Qt-related components of
PLplot such as the devices provided by our "qt" device driver would be
automatically dropped by our build system when it did not find Qt5,
but other excellent choices for devices such as those provided by our
"cairo" device driver would still be available (assuming our build
system finds on Slackware the Pango and Cairo libraries upon which our
"cairo" device driver depends).

By the way, Slackware was my very first Linux distribution (in 1996 on
a pentium-133).  Happy days!

Alan
__________________________
Alan W. Irwin

Programming affiliations with the FreeEOS equation-of-state
implementation for stellar interiors (freeeos.sf.net); the Time
Ephemerides project (timeephem.sf.net); PLplot scientific plotting
software package (plplot.org); the libLASi project
(unifont.org/lasi); the Loads of Linux Links project (loll.sf.net);
and the Linux Brochure Project (lbproject.sf.net).
__________________________

Linux-powered Science
__________________________