Re: [Interest] [Development] Windows 7 support will be, dropped in Qt 6
On 06/18/20 19:27, Roland Hughes wrote: We are all just waiting on KDE to pull the trigger and tell us what library(ies) will be used in the post-Qt world. The current licensing and royalty situation make Qt unusable going forward. There is no post-Qt world from the KDE point of view. It is impossible to port hundreds of applications to a different toolkit, and this is the reason we secured the availability of Qt in source code form under a free software license via written agreements. BG, Christoph Feck ___ Interest mailing list Interest@qt-project.org https://lists.qt-project.org/listinfo/interest
Re: [Interest] Qt3D performance, and development resources
Thanks to all for the interesting C++ Qt3D links! I long wanted to play with Qt3D in C++. RHI supporting all major 3D APIs makes it really attractive. Christoph Feck ___ Interest mailing list Interest@qt-project.org https://lists.qt-project.org/listinfo/interest
Re: [Interest] Best way to threaded render (images) going forward?
On 11/19/19 19:52, Wesley Krasko wrote: Yes, I've read about RHI but it all seems to imply it's for QT Quick, what about Qt Widget based apps going forward? Let me quote what is written there: "We will need to base all our rendering infrastructure (QPainter, the Qt Quick Scenegraph, and our 3D support) on top of that layer." QWidgets use QPainter for rendering. Is my best bet QOpenGLWidget until 6.x comes out then and then re-write again? If you are using OpenGL, RHI won't magically change your code. Use QPainter, the Qt Quick scene graph, or Qt3D, depending on your case. ___ Interest mailing list Interest@qt-project.org https://lists.qt-project.org/listinfo/interest
Re: [Interest] Best way to threaded render (images) going forward?
On 11/19/19 19:33, David M. Cotter wrote: is someone working on something like QNativeGraphics, which picks the best impl under the hood? eg: metal for macos, opengl for linux, and whatever it is now for windows? See https://www.qt.io/blog/2019/08/07/technical-vision-qt-6 ___ Interest mailing list Interest@qt-project.org https://lists.qt-project.org/listinfo/interest
Re: [Interest] QPainter drawLine zValue?
On 09/25/19 19:13, Israel Brewster wrote: Is there a way to set the Z value of the line drawn by the QPainter::DrawLine() function? I have a library that uses the drawLine function to create a grid, and I would like to keep the grid on the top as I draw other things, if possible. Thanks. QPainter has no concept of a Z value. I suggest to look at QGraphicsView; it allows placing items with a Z coordinate, but also has support for permanent background and foreground graphics, either via brush or callback functions. To minimize porting, you could wrap all your "other" painter calls into a single QGraphicsItem; but you could also split your scene into multiple smaller items. ___ Interest mailing list Interest@qt-project.org https://lists.qt-project.org/listinfo/interest
Re: [Interest] Question Regarding Porting Gtk To PyQt
On 06/17/19 03:57, Christoph Feck wrote: * https://doc.qt.io/qtforpython/PySide2 * https://doc.qt.io/qtforpython/ ___ Interest mailing list Interest@qt-project.org https://lists.qt-project.org/listinfo/interest
Re: [Interest] Question Regarding Porting Gtk To PyQt
On 06/17/19 03:29, Samuel Banya wrote: Hello everyone, I'm having a bit of difficulty of helping the Lubuntu team port a program called RedShift from Gtk to PyQT. The reason is that the Qt docs are primarily C++ based, and though I know there is a PyQt variant that focuses on Python, its not as up to date as the ones present for the C++ variant of the docs. Qt docs include PySide documentation, but not PyQt documentation: * https://doc.qt.io/qtforpython/PySide2 That being said, I have my current progress of trying to port this Gtk program to PyQt here: https://github.com/SBanya/redshift-1.12 If someone could take a look at the commented sections in the controller.py for starters, I'd really appreciate it since I'm having difficulty on finding the exact Gtk variant present: https://github.com/SBanya/redshift-1.12/blob/master/redshift-1.12qt/src/redshift-qt/controller.py Thank you for reading my message! Spawning external processes is done with QProcess: * https://doc.qt.io/qtforpython/PySide2/QtCore/QProcess.html Note that QProcess is an QIODevice, so the output streams of the external process can be monitored with its signals. QFileSystemWatcher is used for 'inotify' handling, so unrelated. For low-level (Linux) signal handling use QProcess.processId(). HTH, Christoph -- Christoph Feck ___ Interest mailing list Interest@qt-project.org https://lists.qt-project.org/listinfo/interest
Re: [Interest] Qt::GlobalColor to pixel value
On 03/19/19 19:25, Jason H wrote:
What is the simplest way to go from:
QList pallette
{Qt::black,Qt::red,Qt::darkRed,Qt::green,Qt::darkGreen,Qt::blue,Qt::darkBlue,Qt::cyan,Qt::darkCyan,Qt::magenta,Qt::darkMagenta,Qt::yellow,Qt::darkYellow};
To a pixel QRgb?
image.setPixel(x,y, pallette[5]);
The .toRgb() of QColor does not actually return a QRgb, instead it converts the
color to RGB representation internally.
I've hacked this:
uint toRgb(const QColor ) {
return qRgb(c.red(), c.blue(), c.green());
}
image.setPixel(x,y, toRgb(pallette[5]));
but it seems so obtuse.
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https://doc.qt.io/qt-5/qcolor.html#rgb
or use https://doc.qt.io/qt-5/qimage.html#setPixelColor
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Re: [Interest] vs. Flutter
On 02/19/19 20:47, Jason H wrote: What I've learned is that it's better to stand on the shoulders of giants than to rewrite the universe from scratch. I dream of a say where we can code things and everyone else regardless of platform can run it. I thought this was going to be .Net CLR, or Java VM, but corporate ownership initiatives derailed them (Much like the "You will" ATT ads of the 90s - we got it, but not from ATT). But C/C++ runs all more platforms/processors. Linux has come a long way in terms of bringing all CPUs a usable software ecosystem. And this though rather obtuse is one reason to pick Qt - that it'll support any system that can run a C++ compiler. You don't technically need to use QML, you can keep going with C++. Once upon a time a mother of two curious boys called me, asking me to teach them programming. They have no clue what language to start with, so I suggested C as a base, to later learn Python, C++, Java (or C#). Then some "smart" student told one of the kids "JavaScript is da future of da Internetz". I stopped teaching them after it was suggested to stop the C course and swap it for a JavaScript course. C/C++ will be relevant in the future. All other languages will come and go (no pun intended). Whether Qt will be relevant in the future lies in the hands of its developers. Don't ruin it. Christoph Feck ___ Interest mailing list Interest@qt-project.org https://lists.qt-project.org/listinfo/interest
Re: [Interest] Priority of bugs
On 20.09.2018 14:59, Krzysztof Kawa wrote: [...] If a new feature has a bug I just don't start to use it, no problem, but if something breaks after update I'd like to at least know I can skip a release and wait for a fix. While this makes sense, in practice most bug fixing is spent to make the new features actually work. There is no point in adding features, if they are not useable because of bugs. Since time and developer resources are limited, even that goal is hardly reached, so it seems natural that fixes for other issues need additional help and/or additional time. Also note that everyone has their own favorite bugs. For example, I am still using Qt 4 for one of my applications because of QTBUG-57485, but hey, Qt 4 still works :) -- Christoph Feck KDE Bug Triaging Team ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] Complex border from QPainterPath
On 29.06.2018 19:19, Patrick Stinson wrote:
I am trying to construct a text callout QGraphicsItem. It is basically a rounded
rect plus some triangular protrusions from the rect center to various points
outside the rounded rect (see screenshot).
See attached example code.
#include
#include
#include
#include
#include
int main(int argc, char *argv[])
{
QApplication app(argc, argv);
QImage im(800, 600, QImage::Format_RGB32);
im.fill(Qt::black);
QRectF bubble(500, 100, 200, 80);
QPainterPath path;
const double r = qMin(bubble.width(), bubble.height()) / 2;
path.addRoundedRect(bubble, r, r);
QList markers = {QPointF(200, 500), QPointF(400, 400), QPointF(600, 500)};
for (QPointF mark : markers) {
QPainterPath marker;
marker.moveTo(mark);
QLineF side(bubble.center(), mark);
side = side.normalVector();
side.setLength(r / 2);
marker.lineTo(bubble.center() + QPointF(side.dx(), side.dy()));
marker.lineTo(bubble.center() - QPointF(side.dx(), side.dy()));
marker.closeSubpath();
path = path.united(marker);
}
QPainter p;
p.begin();
p.setBrush(Qt::white);
QPen pen(Qt::red);
pen.setWidth(5);
pen.setCapStyle(Qt::RoundCap);
pen.setJoinStyle(Qt::RoundJoin);
pen.setMiterLimit(1);
p.setPen(pen);
p.drawPath(path);
p.drawText(bubble, Qt::AlignCenter, QStringLiteral("Here we are"));
p.end();
QLabel label;
label.setPixmap(QPixmap::fromImage(im));
label.setFixedSize(im.size());
label.show();
return app.exec();
}
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Re: [Interest] Can't set line height for QPlainTextEdit
On 06.06.2018 03:52, nus1998 wrote: I want to set line height for QPlainTextEdit, here is my code, but it doesn't work, the line height is always same as the font height. btw: If I change QPlainTextEdit to QTextEdit, then it works. QPlainTextEdit has vastly simpler layouting code to speed up text where formatting is not relevant (e.g. log files). As such, it is most certainly intended to ignore the request for additional block formatting commands. ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] QDatastream, QMap, QImage serialization
On 21.05.2018 16:36, Murphy, Sean wrote: Why is QImage even a GUI type? "Has pixels" is the simplest defintiion of GUI. As a counter to that: QImage be safely used outside of the GUI thread which is not true for most classes that are considered GUI classes... But doesn't QImage need PNG to serialize data? I wouldn't want a libpng dependency in command line applications. Maybe for Qt6 we could have a thin QtGuiCore library, which manipulates image data and colors, but does not have a dependency on GUI servers (OpenGL, X11, etc.) ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] QImage transformed() background color
On 07.05.2018 21:56, Jason H wrote:
I'm rotating some images by non-90 degree amounts, but when I do, the image
gets filled with a color value (black) for pixels where there is no image data
after rotation, but are in the output image, which causes a problem with later
analysis because it trips edge detection. It would be nice to be able to
control the fill color, or better yet, not have any fill as a result of the
rotate, and just use want's in the image. Ideally, I'd like to pass it a
fillColor (Qt::transparent) so that I can just look at the alpha channel and
ignore pixels with a 0 alpha. How can I accomplish that if I can't select the
color?
I don't know that it's possible to select the rotated rectangle out and draw it
on a transparent image with a QPainter?
QImage rotate(const QImage , double degrees){
if (degrees > 0.01 || degrees < -0.01) {
QTransform tx;
QPoint center = image.rect().center();
tx.translate(center.x(), center.y());
tx.rotate(degrees);
return image.transformed(tx, Qt::SmoothTransformation);
} else {
return image;
}
}
The rotated image is filled with transparent pixels for ARGB images. You
can use QPainter compositing to paint that image on any colored
background (or on your original image).
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Re: [Interest] XML parsing
On 17.07.2017 21:25, Francisco Ares wrote:
Hi, all.
I'm pretty new to programming, in special regarding XML generation and
parsing.
Could anyone help me parse the following file?
1
3.0
SingleFrame
Meaning 3 settings in a device, one on each line that shows first the type
of the setting, the name to which this device's API would respond to, then
the new value for that setting.
For now, I have the following, mostly from samples:
QDomDocument doc("mydocument");
QFile file("myfile.xml");
if (!file.open(QIODevice::ReadOnly))
return;
if (!doc.setContent()) {
file.close();
return;
}
file.close();
QDomElement docElem = doc.documentElement();
QDomNode n = docElem.firstChild();
while(!n.isNull()) {
QDomElement e = n.toElement(); // try to convert the node to an element.
if( ( !e.isNull() ) && n.isElement() ) {
QString aType = e.nodeName();
QString aValue = e.text();
}
n = n.nextSibling();
}
This returns me the the type and the value, but I could not find a way
to obtain the name of the setting (for instance, "AcquisitionMode" on
line 3.
Any help will be highly appretiated!
Thanks,
Francisco
Use QDomElement::attribute() or QDomElement::attributeNode().
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Re: [Interest] WindowStaysOnTopHint on Windows always on top?
On 10.07.2017 19:19, John Weeks wrote: We have a QWidgets application that uses WindowStaysOnTopHint for certain windows. My expectation is that when the application isn't the active application, the floating windows should not be visible. But in our application they are visible always. Is this expected? Maybe I should file a bug on this behavior. In Plasma's window manager KWin, there is an option for this, so I guess it decided by the window manager, not Qt. ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] QT expert's help required for mentoring Linux Foundation GSoC project.
On 09.06.2017 17:17, Aveek Basu wrote: This is Aveek from Linux Foundation. Currently myself and Till Kempeter, are working as the org admins of the LF GSoC project. This year have undertaken a project of developing the Common Print Dialog for Linux ( https://wiki.linuxfoundation.org/gsoc/google-summer-code-20 17-openprinting-projects). This project will for sure improve the user experience on how we all print in Linux today. The project involves development of the complex Common Print dialogs in QT. We are badly in need of someone who has development experience in QT upstream to guide our students. It will be of great help if someone from the community could could show interest. Is the aim to merge this printing dialog into Qt sources to replace the current Qt print dialog? http://doc.qt.io/qt-5/qprintdialog.html If yes, then the GSoC students should contact Qt developers at the Qt development mailing list, and discuss their plans. Unfortunately, the former QPrinter maintainer is busy with his paid job, so I see difficulties here. If not, then I suggest that the GSoC students just post questions to the Qt interest mailing list, #qt IRC channel, or official Qt forum at https://forum.qt.io/ Please do not use any other Qt mailing list. ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] Syncing tree views.
On Friday 29 July 2016 17:14:08 william.croc...@analog.com wrote: > On 07/29/2016 11:07 AM, Christoph Feck wrote: > > On Friday 29 July 2016 16:58:31 william.croc...@analog.com wrote: > >> On 07/29/2016 10:33 AM, Christoph Feck wrote: > >>> On Friday 29 July 2016 16:14:41 william.croc...@analog.com wrote: > >>>>>> applies to items which are common to both.) > >>>>> > >>>>> KF5 has a solution for that. I'm not an Model/View expert, > >>>>> but i think this is what you're looking for: > >>>>> > >>>>> https://api.kde.org/frameworks/kitemmodels/html/classKLinkIte > >>>>> mS el ectionModel.html > >>>> > >>>> Thanks for the pointer. Alas... > >>>> - I am industry and this is GPL. > >>> > >>> KDE libraries and frameworks are LGPL. > >> > >> The commentary at the top of the associated files, > >> as linked above, says GPL. > >> > >> This library is free software; you can redistribute it > >> and/or > >> > >> modify it under the terms of the GNU Library General Public > >> License as published by the Free Software Foundation; either > >> version 2 of the License, or (at your option) any later version. > > > > Which part of "Library General Public License" is not LGPL? > > IIRC: The first 'L' in LGPL stands for 'Lesser', not 'Library'. For version 2 (which the above text refers to), it was called "Library". You are free to use the later versions, whatever name they now have. See https://www.gnu.org/licenses/old-licenses/lgpl-2.0.en.html > >>>> - I do not currently use any KDE and > >>>> > >>>> I do not like adding dependencies. > >>> > >>> Dependencies besides qtbase? > >> > >> I use the Qt modules, but little more. > > > > Remember that adding KItemModels, or other Tier 1 frameworks > > listed on https://api.kde.org/frameworks/index.html is > > equivalent to adding other Qt dependencies, e.g. QtSvg or > > QtXmlPatterns, because those only require qtbase. > > Yes. I use all of those Qt module and have no problem with that. Exactly. If you have a problem with KItemModels, or other Tier 1 frameworks marked "functional", then we would love to know. The initial letter "K" cannot be the issue :) ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] Syncing tree views.
On Friday 29 July 2016 16:58:31 william.croc...@analog.com wrote: > On 07/29/2016 10:33 AM, Christoph Feck wrote: > > On Friday 29 July 2016 16:14:41 william.croc...@analog.com wrote: > >>>> applies to items which are common to both.) > >>> > >>> KF5 has a solution for that. I'm not an Model/View expert, but > >>> i think this is what you're looking for: > >>> > >>> https://api.kde.org/frameworks/kitemmodels/html/classKLinkItemS > >>> el ectionModel.html > >> > >> Thanks for the pointer. Alas... > >> - I am industry and this is GPL. > > > > KDE libraries and frameworks are LGPL. > > The commentary at the top of the associated files, > as linked above, says GPL. > > This library is free software; you can redistribute it and/or > modify it under the terms of the GNU Library General Public > License as published by the Free Software Foundation; either > version 2 of the License, or (at your option) any later version. Which part of "Library General Public License" is not LGPL? > >> - I do not currently use any KDE and > >> > >> I do not like adding dependencies. > > > > Dependencies besides qtbase? > > I use the Qt modules, but little more. Remember that adding KItemModels, or other Tier 1 frameworks listed on https://api.kde.org/frameworks/index.html is equivalent to adding other Qt dependencies, e.g. QtSvg or QtXmlPatterns, because those only require qtbase. ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] Syncing tree views.
On Friday 29 July 2016 16:14:41 william.croc...@analog.com wrote: > >> applies to items which are common to both.) > > > > KF5 has a solution for that. I'm not an Model/View expert, but i > > think this is what you're looking for: > > > > https://api.kde.org/frameworks/kitemmodels/html/classKLinkItemSel > > ectionModel.html > > Thanks for the pointer. Alas... > - I am industry and this is GPL. KDE libraries and frameworks are LGPL. > - I do not currently use any KDE and >I do not like adding dependencies. Dependencies besides qtbase? ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] harfbuzz support?
On Sunday 12 April 2015 01:20:36 René J.V. Bertin wrote: Hi, Qt can be built with or without support for text rendering using harfbuzz. Harfbuzz is responsible for layout (positioning) of glyphs, not rendering them to bitmaps. ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] Bounties?
On Saturday 14 March 2015 00:20:27 Bo Thorsen wrote: When you need to have a bug fixed, pay someone to do it. I guess those willing to pay have a problem finding someone having time to work on it. Why not simply have a page in the Qt wiki with contact addresses of developers that offer pay-per-bug support, instead of pay-per-year support? KDAB was mentioned, but I guess there are many more. -- Christoph Feck https://kdepepo.wordpress.com/ KDE Quality Team ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] Question about using QtDBus
On Thursday 28 August 2014 19:17:54 Rogers Nate wrote: Confidentiality Notice: The preceding e-mail message (including any attachments) contains information that may be confidential, protected by applicable legal privileges, or constitute non-public information. It is intended to be conveyed only to the designated recipient(s). If you are not an intended recipient of this message, please notify the sender by replying to this message and then delete it from your system. Use, dissemination, distribution or reproduction of this message by unintended recipients is not authorized and may be unlawful. I deleted this message from my system. -- Christoph Feck http://kdepepo.wordpress.com/ KDE Quality Team ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] QWidget + friends; How to restore properties across sessions?
On Friday 15 August 2014 21:48:08 Mark Gaiser wrote: Now i'm searching for alternatives to this approach to prevent handling the bookkeeping myself and still have the same result. For instance, would it be possible to have some function (in QObject or QWidget i guess) where you either: - Define which properties should be saved/restored across sessions, bookkeeping would be done internaly. - or just some QObject::persistentSettings(bool) function that - when true - saves any properties and restores them upon next request in a persistent manner. Each QMetaObject has a userProperty() which identifies the value that the user can change in the object. To get a key for the settings file, you can use special objectName()s. For example, in Smaragd, I prefix any object that should have a persistent user property with cm_ (for config manager). See code at [1]. In Skulpture, there are two older versions of this file, one of them uses QSettings[2] instead of KConfigGroup[3]. Those additionally handle oddities with combo boxes, but they do not use userProperty(). [1] https://projects.kde.org/projects/playground/artwork/smaragd/repository/revisions/master/entry/src/config/configmanager.h [2] http://quickgit.kde.org/?p=scratch%2Fcfeck%2Fskulpture.gita=blobh=43b6b8a73c34c54befe3a8289908e6a8d6344077hb=431fdd98819adc8ac1890c01312b81f08f68562ff=src%2Fconfig%2Fconfigmanager.h [3] http://quickgit.kde.org/?p=scratch%2Fcfeck%2Fskulpture.gita=blobh=c9816cacd6bec235e776e314c9ea5400d2fb44behb=431fdd98819adc8ac1890c01312b81f08f68562ff=kwin-client%2Fconfig%2Fconfigmanager.h -- Christoph Feck http://kdepepo.wordpress.com/ KDE Quality Team ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] OpenGL drivers
On Friday 29 November 2013 13:30:10 Sletta Gunnar wrote: Long term, the solution for Qt might be that we bundle a software GL implementation (llvmpipe for instance) and switch to that if a driver is too problematic for us. Hopefully, we can get by with applying workarounds in Qt though. So, I'm asking that if you encounter issues with flickering, crashes, bad rendering and similar, help us track which things are problematic by filing a bugreport on bugreports.qt-project.org Is there a simple way to stress test Qt's OpenGL support? I have Qt stable branch (5.2.0+) installed on my system, but do not have the time and expertise to code OpenGL apps, yet I want to help testing it. -- Christoph Feck http://kdepepo.wordpress.com/ KDE Quality Team openSUSE Review Team ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] Font measuring inconsistency between platforms in Qt5? Or, how best to draw characters with QPainter.
On Sunday 29 December 2013 18:16:29 George Tasopoulos wrote: QFont font(Liberation Mono, 18, QFont::Normal, false); QFontMetrics metrics(font); int x = metrics.height(); On Windows x equals 27, which seems to be the correct value, but on Linux it equals 28. The (pixel) height of the font is determined by DPI of the display, so it is correct that on different systems you get different results for the font metrics. After all, that's the reason the QFontMetrics class is provided, so that you can adapt to the resulting metrics. -- Christoph Feck http://kdepepo.wordpress.com/ KDE Quality Team openSUSE Review Team ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] Plastique style stylesheets
On Monday 23 December 2013 12:17:34 Etienne Sandré-Chardonnal wrote:
Hi,
I am trying to use the plastique style and change its colors to a
dark theme.
However, simply doing :
QWidget
{
color: #b1b1b1;
background-color: #323232;
}
Messes several things including scrollbars:
[image: Images intégrées 1]
As you can see, the double arrow in the bottom is removed, the
round corners are lost, etc... So it seems that plastique is not
fully stylable.
Is there a workaround, or a more customizable style in Qt4? Or is
it time to switch to Qt5 and fusion?
First, why not simply let the user decide about the color theme? Is
hardcoding colors a new trend?
Second, style sheets _are_ a workaround. They are not meant to create
a custom style. Subclass QStyle instead, if you want to do your own
rendering.
And last, do not expect changes in Qt5 regarding style sheets.
--
Christoph Feck
http://kdepepo.wordpress.com/
KDE Quality Team
openSUSE Review Team
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Re: [Interest] 5.2 RC1 - release
On Thursday 12 December 2013 22:57:03 Mark Gaiser wrote: Where is the page with new C++ classes and new QML types/properties? doc.qt-project.org is pointing to http://qt-project.org/doc/qt-5/index.html for 5.2 which doesn't show a whats new page. Well, it does, but that is 5.0, not 5.2. Reading that page, I will find a link to What's New in Qt 5.2. ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] QGraphicsItem and mouse events
On Saturday 02 November 2013 23:21:24 Igor Mironchik wrote: By default QGraphicsItem must be movable by mouse but he doesn't... What does the Qt documentation state about the default value for QGraphicsItem::flags()? -- Christoph Feck http://kdepepo.wordpress.com/ KDE Quality Team ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] Default action for a QMenu added to a QToolBar
On Tuesday 20 August 2013 19:27:03 Etienne Sandré-Chardonnal wrote: Dear all, I inserted a QMenu to a QToolBar. This displays the menu icon, together with a drop-down arrow for opening the menu. Clicking the menu icon in the toolbar does nothing, as the menu action is connected to nothing. Is it possible to either: - Set the default child action that will be triggered when the main menu icon is clicked (setDefaultAction doesn't do the job) - Popup the menu when the main menu icon is clicked (as when clicking the dropdown arrow) Thanks, Etienne http://qt-project.org/doc/qt-4.8/qtoolbutton.html#ToolButtonPopupMode-enum ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] ItemDelegate and word wrapping
On Friday 01 February 2013 12:59:43 Иван Комиссаров wrote: So, what should i do?) Should i hardcode style names that support drawing fancy background and emulate in other cases? From looking at KDE code, we use style-drawPrimitive(QStyle::PE_PanelItemViewItem, opt, painter, opt.widget); instead of style-drawControl(QStyle::CE_ItemViewItem, opt, painter, widget); to draw the item's background. See kdelibs/kdeui/paged/pageview_p.cpp line 419+. -- Christoph Feck http://kdepepo.wordpress.com/ KDE Quality Team ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] Problems porting to Qt5
On Friday 04 January 2013 21:42:59 Nikos Chantziaras wrote: I'm not using anything from KDE, actually. The application compiles just fine with Qt5. The whole point is that Qt5 applications don't have a native look under KDE. If you mean the Oxygen look, then yes, your application uses parts of KDE, because Oxygen is the KDE style, in other words, you are not using a native Qt style. -- Christoph Feck http://kdepepo.wordpress.com/ KDE Quality Team ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] HierarchicalHeaderView for a QTableView
On Thursday 15 November 2012 08:00:49 Alex Strickland wrote: On the plus side, the little example finally lifted the veil from my eyes about how MVC should work - I deleted tons of code and had a better solution. Just curious, because this can be misinterpreted. Did you delete all the MVC code, because it was too complicated, and you now have a better solution, or did you delete old code, because the MVC implementation is much simpler now? -- Christoph Feck http://kdepepo.wordpress.com/ KDE Quality Team ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] How can i manipulate pixel data from a QWidget?
On Saturday 22 September 2012 21:25:42 Mark wrote: I could really use some way to get the widget pixel data... If you really want to _get_ the pixels of a widget, you need to grab it using QPixmap::grabWidget() and convert it to a QImage. Note that this is very much slower than keeping an QImage buffer and copying the result to the widget in paintEvent(). -- Christoph Feck http://kdepepo.wordpress.com/ KDE Quality Team ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] QPointF constructor from QPoint
On Wednesday 19 September 2012 04:31:33 Shriramana Sharma wrote: Hello. I ran into this recently: Is there a reason that there is currently (4.8.1) no constructor for QPointF from QPoint? I can understand that QPointF should be explicitly converted to QPoint since it involves a loss of precision but just as integers are accepted everywhere that doubles are, it would be most useful (code less create more) if QPoint is accepted everywhere that QPointF is. Sent from my Android phone The conversion constructor isn't explicit, because on some systems, qreal != double, so conversion from int to qreal actually does involve loss of precision. -- Christoph Feck http://kdepepo.wordpress.com/ KDE Quality Team ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] QLabel with images
On Tuesday 11 September 2012 16:18:54 Konrad Rosenbaum wrote: Create a pixmap and paint the icon and the text over it. Once you've done that for the first time it becomes very easy. There is one issue with rendering text to a pixmap, instead of painting it directly to the widget: You lose subpixel anti-aliasing. -- Christoph Feck http://kdepepo.wordpress.com/ KDE Quality Team ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] QLed
On Sunday 05 August 2012 11:40:41 Phil wrote: Thank you for reading this. I'd like to add an LED widget to my application using Qt Designer. A quick search turned up a Designer plug-in called QLedindicator but I haven't been able to make much sense of it. Is there a QT library that contains an LED widget that I can add to Designer? Screenshot: https://svn.reviewboard.kde.org/r/5369/s/508/ License: LGPLv2+ Code: http://quickgit.kde.org/index.php?p=kdelibs.gita=treehb=frameworksf=tier1/kwidgetsaddons/src Cannot comment on Designer integration; all KDE widgets are integrated there, but I never cared to look how it is done, maybe ask on KDE development mailing lists. -- Christoph Feck http://kdepepo.wordpress.com/ KDE Quality Team ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] QTabBar drawBase property- what does it do?
On Tuesday 24 July 2012 21:34:14 John Weeks wrote: I am in the process of porting code that draws images of controls. Due to history and architecture, I'm not using QWidgets as the basis for these controls, they are drawn using OS primitives. Now I am drawing them with QStyle. There are references amonst the Tab Bar stuff to a base. The QTabBar widget has a property drawBase so I created a test case: a dialog layout with two QTabBars one with drawBase set and the other without. I've looked at Windows, Plastique, CleanLooks, Macintosh and Motif styles and can't see any difference. So... What does drawBase do? What are all those references (especially for QStyle::pixelMetric) to things related to TabBarBase? -John Weeks A QTabWidget usually has a frame around its contents (let's forget about documentMode right now). The tab bar at the top breaks this frame for the active tab, in other words, the QTabBar has to render above the frame drawn by QTabWidget. The amount of pixels the two widgets share the frame is called the overlap. The base is historically the line drawn for a QTabBar, that is actually a visual part of the QTabWidget. Depending on the style, the base might include other graphics at the background. For example, using the Skulpture style, the base graphics is a recessed looking background. See http://kdepepo.files.wordpress.com/2009/05/kde4-style- skulpture.png?w=480 -- Christoph Feck http://kdepepo.wordpress.com/ KDE Quality Team ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] The Proper Way to Mix/Cross-Fade Images
On Tuesday 20 March 2012 14:17:49 Josiah Bryan wrote: I may be crazy, or just aiming for something unrealistic. But here goes: - I want to cross-fade two images over a background. (Simple, right?) Well, not really. Forgot the Cross-fading part - lets just take one point in time, a 50/50 opacity (e.g. the two images we're cross fading each is at 50% opacity.) What would that look like if you just did this straight-forward? (Paint background, paint 1st image at .5 opac, paint 2nd image at .5 opac) Well, it would look like this: http://www.jdbryanphotography.com/fullres/fadetest-bg-renderout.png (200px by 200px PNG image) (For those who don't want to click - the blue background with the word (bg) on it is visible through the partial-opacity B behind the partial-opacity A) This would be coded like: double opac = .5; p.setOpacity(1.0-opac); p.drawImage(0,0,image1); p.setOpacity(opac); p.drawImage(0,0,image2); // render this image now over the background and you get the above link's image But I don't think the background should show thru - if each image is exactly 50% opac, in my (simple) mind, that should add up to 100% opacity - This is what I want to see: http://www.jdbryanphotography.com/fullres/output-goal.png (200px by 200px PNG image) (No clicky? Solid red background with partial-opacity A over partial opacity B) However, the best so far that I can come up with (without cheating) is this: http://www.jdbryanphotography.com/fullres/output-bestsofar.png (200px by 200px PNG image) (No clicky? 75% red bg with same partial-opacity letters.) Here's the source of the example (self-contained, 116 lines of cpp): http://www.jdbryanphotography.com/fullres/main.cpp Using the following images as source: http://www.jdbryanphotography.com/fullres/fadetest-A.png http://www.jdbryanphotography.com/fullres/fadetest-B.png http://www.jdbryanphotography.com/fullres/fadetest-bg.png (Basically, I render the image as above, then I create another image to use as the alpha channel, extract the alpha channels of the first two images (image1 and image2), then render them the same way (1.0-opac, draw, opac, draw), then I set the alpha channel image as the alpha channel on the first rendered image) ** The main problem I can't figure out ** My main.cpp example linked here would work perfectly for my problem, EXCEPT that even when mixing the alpha chan properly, the resultant image is 25% darker than it should be - e.g. the solid red areas in -bestsofar.png are 189 red instead of 255 red. Shouldn't 50% of red from fadetest-A.png at pixel X,Y mixed with 50% red from fadetest-B.png at the same pixel X,Y be 100% red in the output image? (Well, I can force it to render how I want - just render the first image with 100% opacity - see the comment about Want to cheat? in the main.cpp. But if I cheat, that wouldn't work for images that have different areas with different opacities - say trying to crossfade between two words (100% opacity) rendered on a 30% black background.) ** The other (side) problem ** This method is dog-slow - 4ms for me just to render and set the alpha channel (not to mention the 4ms to render the initial mixed image.) And thats with a 200x200 image - I'm talking about doing this with 1024x768px-sized images - which would (if I extrapolate correctly) be about 20-50ms a frame - ouch. So it all boils down to this: Is there any way to force QPainter (or, heck, just do it on a raw OpenGL surface and skip QPainter/QImage all together) to blend things where 50% opacity + 50% opacity = 100% opacity in the resultant image? Or, as some might say, am I just waa off base here? Perhaps the mere mention of this idea is causing Porter and/or Duff to want to smack me with a stick...I don't know. Any thoughts? Anyway, thanks for your thoughts and feedback. Cheers! -Josiah Here https://projects.kde.org/projects/playground/artwork/smaragd/repository/revisions/c71af7bc12611e462426e75c3d5793a87b67f57e/diff is the code change I did in Smaragd when I faced the same problem. From what you can see in the deleted code, I tried to render one image with 1 - a and the other image with a opacity, but that did not work as you noticed. The added helper function solved the issue, but it does not handle images of different sizes. -- Christoph Feck http://kdepepo.wordpress.com/ KDE Quality Team ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] [ Missing pixels when using drawLine ]
On Tuesday 13 March 2012 08:28:04 ashish raste wrote: *Dear all, Recently I worked on a paint application, where I implemented a function to draw whatever a user is scribbling on an image. In the mouseMove event, I called a function to draw with the previous point and the current point as its arguments, using the drawLine function of QPainter. Now, I noticed that the pixels sent to this function are not continuous but some in-between pixels were being left. I assume that this is due to the delay for a user-kernel and kernel-user mode switch when calling the underlying paint-engine's functions to draw the line. If this only appears since Qt 4.8 with raster engine, this could be https://bugreports.qt-project.org/browse/QTBUG-23430 As a workaround, use drawPixel() for single-pixel lines. I have looked-up in the documentation of Qt-painting to find how it internally calls drawLines(), which instead creates a qpainterPath to draw a curve, line or whatever we scribble. But I couldn't find how the missing pixels were added in between just knowing the start and end point of a line (though we know that a curve will contain a large set of small lines, each having a start and end point) Is there anyway to track these missed pixels i.e to track all the pixels which are being drawn? Thanks you!* -- Christoph Feck http://kdepepo.wordpress.com/ KDE Quality Team ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] QTextEdit and Style sheets
On Tuesday 13 March 2012 16:52:21 André Somers wrote: Op 13-3-2012 16:45, Graham Labdon schreef: Hi everyone Solved this! edit-setStyleSheet(background-image:url(:/images/bg.jpg)); QPalettepalette=edit-palette(); palette.setBrush(QPalette::Base,Qt::NoBrush); edit-setPalette(palette); Please report this as a bug. I think that setting a background image should already set the brush to NoBrush, or the rendering should be done the other way around. Either way, that would qualify as a Qt bug IMO. André You have to change the background of the viewport() instead, otherwise the viewport will render its background over that of the QTextEdit object. So it is not a bug, but expected behavior. Using setPalette() also affects the viewport, because the palette attribute is inherited by children. -- Christoph Feck http://kdepepo.wordpress.com/ KDE Quality Team ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
