[MacPorts] #57577: qt4-mac : set the graphicssystem via qtconfig

[MacPorts]

#57577: qt4-mac : set the graphicssystem via qtconfig
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  Reporter:  RJVB         |      Owner:  michaelld
      Type:  enhancement  |     Status:  assigned
  Priority:  Normal       |  Milestone:
 Component:  ports        |    Version:
Resolution:               |   Keywords:  haspatch
      Port:  qt4-mac      |
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Comment (by RJVB):

 Replying to [ticket:57577 RJVB]:
 > It should be possible however to implement a setting controlled through
 qtconfig but used (applied) only by kdelibs4 (in the `KApplication`
 class).

 I have a PoC but I'm not sure if it's that good of an idea to add an
 additional setting applying only to KDE apps in qtconfig. After all,
 raster mode became the default in Qt5.

 The further tinkering did allow me to notice something else:

 Setting raster mode as early as done by the attached patch appears to
 solve the graphics glitch when using the Oxygen or Breeze styles, where
 (menu) items would appear and disappear when you move the mouse over their
 parent widget. It doesn't make sense to me, but it appears to be a fact.

-- 
Ticket URL: <https://trac.macports.org/ticket/57577#comment:2>
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