9 Mar
2013
9 Mar
'13
12:16 a.m.
Hi everyone!
This week I've been playing with DraftSight both on Linux and on Windows.
DraftSight is a Qt4 CAD drawing program that is very similar to AutoCad and it is
available for free both for Windows and for Linux.
I used DraftSight for many months on Linux on my Core 2 Duo with 2gb of RAM computer and
it is sluggish. Each time that I select a part of the drawing to modify an attribute there
is a 5-10 second delay before the program unfreeze.
On my Windows-only laptop that I use mainly for running industrial automation software, I
have installed DraftSight this week. This laptop is an old IBM ThinkPad A31p with a 1.7GHz
Pentium 4 cpu and 512mb of RAM. It runs Windows XP. On this laptop, DraftSight runs
perfectly well and there is no delay when I click on a part of a drawing, even if it is a
much slower computer and the general performance of DraftSight is much better on Windows.
Is there a reason why I see such a big difference between this Qt4 program on Linux and on
Windows? Does the difference is because of Qt4 or it could be because DraftSight has not
been ported as well as it could be?
Qt3 has a very high performance and on a slow computer, it is even faster than GTK2. The
UI element are drawn faster than almost every other GUI toolkits. Why does QT4 still
suffer from these performance issues?
Have an happy spring break!
-Alexandre
9 Mar
9 Mar
12:36 a.m.
New subject: [trinity-users] Poor Qt4 performance on Linux
Hi everyone!
This week I've been playing with DraftSight both on Linux and on Windows.
DraftSight is a Qt4 CAD drawing program that is very similar to AutoCad
and it is available for free both for Windows and for Linux.
I used DraftSight for many months on Linux on my Core 2 Duo with 2gb of
RAM computer and it is sluggish. Each time that I select a part of the
drawing to modify an attribute there is a 5-10 second delay before the
program unfreeze.
On my Windows-only laptop that I use mainly for running industrial
automation software, I have installed DraftSight this week. This laptop is
an old IBM ThinkPad A31p with a 1.7GHz Pentium 4 cpu and 512mb of RAM. It
runs Windows XP. On this laptop, DraftSight runs perfectly well and there
is no delay when I click on a part of a drawing, even if it is a much
slower computer and the general performance of DraftSight is much better
on Windows.
Is there a reason why I see such a big difference between this Qt4 program
on Linux and on Windows? Does the difference is because of Qt4 or it could
be because DraftSight has not been ported as well as it could be?
Qt3 has a very high performance and on a slow computer, it is even faster
than GTK2. The UI element are drawn faster than almost every other GUI
toolkits. Why does QT4 still suffer from these performance issues?
Have an happy spring break!
-Alexandre
My general understanding is that Linux has become something of a
second-class citizen with Qt4/Qt5; rather than optimising the graphics
code for X11 as Qt3 did, it uses the CPU to draw all elements, then only
uses the graphics card for certain 3D operations and transformations.
While I don't have all the links handy right now, a quick Google search
turned up these related links:
https://bugreports.qt-project.org/browse/QTBUG-19636?focusedCommentId=17770…
http://phoronix.com/forums/showthread.php?73736-Qt5-s-Linux-Requirements-Ca…
This may change in Qt5, but would then rely heavily on powerful, non-free
graphics hardware to function (scenegraph backend). As another ancdotal
datapoint, I have noticed that Qt4-based applications have always been
significantly slower than equivalent Qt3 applications. Note that
"equivalent" in this case means displaying a similar number of on-screen
widgets; many Qt4 applications have had so much functionality stripped out
and/or hidden behind a bulky "touch" interface that direct comparisons are
quite difficult.
Between the noted performance problems and the fact that the Qt project
seems to be completely unable to resolve several bug reports related to
incorrect graphics primitive drawing (for example,
https://bugreports.qt-project.org/browse/QTBUG-25896), it would appear
that the TDE project's decision to stick with Qt3 was the correct
decision.
Tim
11:34 a.m.
New subject: [trinity-users] Poor Qt4 performance on Linux
On Saturday 09 March 2013 01.36:40 Timothy Pearson wrote:
(...)
My general understanding is that Linux has become
something of a
second-class citizen with Qt4/Qt5;
(...)
Not surprising as long as it was a Nokia business. Any hope that Digia does
better? (Wikipedia writes: "About 125 Qt developers were transferred to
Digia, with the immediate goal of bringing Qt support to Android, iOS and
Windows 8 platforms, and to continue focusing on desktop and embedded
development.". I doubt you can get any performance on an Android device if
the processor has to do all the work.
Thierry
1:35 p.m.
New subject: [trinity-users] Poor Qt4 performance on Linux
My general understanding is that Linux has become
something of a
second-class citizen with Qt4/Qt5; rather than optimising the graphics
code for X11 as Qt3 did, it uses the CPU to draw all elements, then only
uses the graphics card for certain 3D operations and transformations.
While I don't have all the links handy right now, a quick Google search
turned up these related links:
https://bugreports.qt-project.org/browse/QTBUG-19636?focusedCommentId=17770…
http://phoronix.com/forums/showthread.php?73736-Qt5-s-Linux-Requirements-Ca…
This may change in Qt5, but would then rely heavily on powerful, non-free
graphics hardware to function (scenegraph backend). As another ancdotal
datapoint, I have noticed that Qt4-based applications have always been
significantly slower than equivalent Qt3 applications. Note that
"equivalent" in this case means displaying a similar number of on-screen
widgets; many Qt4 applications have had so much functionality stripped out
and/or hidden behind a bulky "touch" interface that direct comparisons are
quite difficult.
Yes, it is true. You can even compare it with programs that
haven't changed at all since KDE3 like KPPP and Ark. The performance is worse on Qt4.
Between the noted performance problems and the fact that the Qt project
seems to be completely unable to resolve several bug reports related to
incorrect graphics primitive drawing (for example,
https://bugreports.qt-project.org/browse/QTBUG-25896), it would appear
that the TDE project's decision to stick with Qt3 was the correct
decision.
Tim
Yes, I 100% agree that the decision to stay with Qt3 is the right one! The
performance of Qt3 is a big part of the reason why I prefer TDE over KDE. It is amazing to
see everything appear just as soon as you click on it!
Thank you for your hard work on TDE!
-Alexandre
5:34 p.m.
New subject: [trinity-users] Poor Qt4 performance on Linux
Hi Guys,
On Saturday 09 March 2013 00:16:01 Alexandre Couture wrote:
Hi everyone!
This week I've been playing with DraftSight both on Linux and on
Windows. DraftSight is a Qt4 CAD drawing program that is very similar
to AutoCad and it is available for free both for Windows and for
Linux.
Like you I use DraftSight on PCLoS.
I used DraftSight for many months on Linux on my Core
2 Duo with 2gb
of RAM computer and it is sluggish. Each time that I select a part of
the drawing to modify an attribute there is a 5-10 second delay
before the program unfreeze.
I find the same problems ! Maybe not quite as severe but certainly the
graphics performance leaves something to be desired. I'm currently
running a dual core 3Gig P4 with 1Gb ram.
On my Windows-only laptop that I use mainly for
running industrial
automation software, I have installed DraftSight this week. This
laptop is an old IBM ThinkPad A31p with a 1.7GHz Pentium 4 cpu and
512mb of RAM. It runs Windows XP. On this laptop, DraftSight runs
perfectly well and there is no delay when I click on a part of a
drawing, even if it is a much slower computer and the general
performance of DraftSight is much better on Windows.
On my laptop, a 1300Mhz 1Gb running Open SuSE 11.1, DraftSight runs a
lot more smoothly without the jerky mouse and refresh delays.
Is there a reason why I see such a big difference
between this Qt4
program on Linux and on Windows? Does the difference is because of
Qt4 or it could be because DraftSight has not been ported as well as
it could be?
?? That could be a question for the DS developers.
Qt3 has a very high performance and on a slow
computer, it is even
faster than GTK2. The UI element are drawn faster than almost every
other GUI toolkits. Why does QT4 still suffer from these performance
issues?
Have an happy spring break!
-Alexandre
--
Best Regards:
Baron
4075
days inactive
4075
days old
4 comments
4 participants
participants (4)
-
Alexandre Couture -
Baron -
Thierry de Coulon -
Timothy Pearson