I'm thrilled to announce that we've released Qt 5.15 LTS today. Qt 5.15 is going to be the last feature release of the Qt 5 series. As such, it is a bit special, and a lot of work has gone into preparations towards Qt 6, our next major release. While Qt 5.15 is supported as usual for all our users, Qt 5.15 will also provide long-term support for three years to all commercial license holders, including the new Qt for Small Business. Option for extended support is available after the three year support period.
As the last release of the Qt 5 series, we wanted to make sure that Qt 5.15 is a great release that you can easily upgrade to with your ongoing projects. It is, as always, fully backward-compatible with previous Qt 5 releases. A large amount of work has gone into bug fixes, and Qt 5.15 is the best and most stable release we've done in the Qt 5 series.
Qt 5.15 also serves as a stepping stone towards Qt 6. While Qt 6 will feature some more substantial changes in Qt's fundamentals, we are trying to keep it as easy as possible to migrate codebases from Qt 5 to Qt 6. To help with that transition, we have flagged a lot of functionality to be removed in Qt 6 as deprecated. Enabling and fixing warnings about deprecated functionality in 5.15 will bring you a long way towards moving your codebase to Qt 6.
But Qt 5.15 also has plenty of new features of its own. To have a look at some of them, read on and/or sign up for the upcoming Qt 5.15 LTS webinar with Tuukka Turunen and myself.
Abstracting 3D graphics APIs
Probably the most significant changes have happened on the graphics side. A lot of the changes are happening under the hood though and are not immediately visible to our users. For the last year, we have been working on a complete revamp of the architecture of our graphics stack. This upgrade will become central in Qt 6 but is already available in Qt 5.15 as an opt-in.
We had built the graphics stack in Qt 5 around the assumption that we can use OpenGL as the cross-platform API for 3D graphics. Over the last couple of years, significant changes in the industry have made developing and deploying applications that use 3D graphics more complicated. Apple started working on Metal and has deprecated OpenGL support on macOS and iOS some time ago. The Khronos group has been working on replacing OpenGL with Vulkan, which is making its way to Android and Linux. Microsoft's Direct 3D 12 is a completely rewritten API and not compatible with older Direct 3D versions at all. At the same time, OpenGL will not be going away for quite some time to come.
With Qt's cross-platform promise, we want to have a solution that works everywhere. To achieve that, we have started working on an abstraction layer for all those different APIs a bit more than a year ago. It's called the Qt Rendering Hardware Interface (RHI) and can be used to run Qt Quick applications on top of Direct 3D, Metal, and Vulkan as well as OpenGL. It is supported as a Technology Preview in Qt 5.15, you can opt into using Qt RHI by enabling it via an environment variable. In Qt 6, this layer will form a very central part of Qt's architecture.
For more details about the RHI, please look at Laszlo's blog posts (here, here, and here) on the topic.
Qt Quick 3D
Another significant new feature of Qt 5.15 is also related to graphics. Back in Qt 5.0 times, we introduced Qt Quick as a cornerstone of Qt's architecture. Its focus was to simplify the creation of animated, touch-based 2D user interfaces. Today, Qt 5.15 comes with a fully-supported Qt Quick 3D, which extends the easy-to-use philosophy to integrating 3D content into Qt-Quick-based applications. With Qt Quick 3D, you can easily define a 3D scene in QML, define your meshes, lights, and materials and combine everything seamlessly with your 2D UI.
Where you needed to develop the 2D and 3D parts separately using different technologies (using Qt 3D, Qt 3D Studio, or raw OpenGL), you now have one integrated solution at your fingertips.
We have developed a cool demo, with which you can test the different features in Qt Quick 3D 5.15, like changing the light type and count, model complexity and count, texture size, materials, and anti-aliasing method and quality, among other things. That way, you can quickly test if, for example, the number of models drawn has more effect on the performance on their hardware than the number of triangles in a model. Here's a video demo:
Qt Quick 3D was introduced as a Technology Preview in Qt 5.14. Qt 5.15's fully supported version makes use of many additional features like support for post-processing effects, a new C++ API for custom geometry, a Quaternion-based API for rotations, and support for spotlights. You can now more easily use 2D Qt Quick inside a 3D scene and at a higher overall performance thanks to a great deal of behind-the-scenes work. Have a look at Andy's talk from the Qt Virtual Tech Con for details.
Qt Design Studio 1.5
Qt Quick 3D adds a huge amount of options to make cool new applications that include both 2D and 3D elements in the user interface. As you might know, we have been putting a significant amount of work into making all of that functionality available to designers through Qt Design Studio. Because of that I am extremely happy to let you know that all of the functionality of Qt Quick 3D is also supported in Qt Design Studio 1.5 that we have also released today. Please have a look at the separate blog post on Qt Design Studio for more details.
Qt QML
With Qt QML we focused on preparing for Qt 6, which has lead to a useful set of new features in Qt 5.15.
QML now has the concept of 'required' properties for components. These are properties that have to be set by a user of the component. Components can now be specified inline in a QML file. We've also added a new, declarative way of registering types.
We have improved the qmllint tool to give you far better warnings about possible problems in your QML code base. We've also added a new qmlformat tool that can help you format your QML files according to our QML coding style guidelines.
Finally, we've also worked on making sure that QML used in Qt for MCUs and Qt 5.15 are compatible.
Qt Quick
A couple of new features have also appeared in Qt Quick. We've added support for color spaces to the Image element and added a new PathText element to Qt Quick Shapes. The pointer handlers have a new cursorShape property to set the shape of the mouse cursor on desktop systems, and a new HeaderView item makes it easy to add horizontal or vertical headers to a TableView.
Other improvements
Our desktop users will be happy to learn that Qt has now much better support for client-side/custom window decorations. This allows you to define your own window decorations and put custom content into the windows title bar space.
Qt Lottie, a module that we introduced as a Technology Preview in Qt 5.14, is now fully supported. The module allows you to integrate After Effects animations into your Qt-based application. Learn more about Qt Lottie in this webinar and this blog post.
Qt WebEngine has been updated from Chromium 77 in Qt 5.14 to Chromium 80 and comes with all the new features from that Chromium update.
Qt 3D has gained better profiling and debugging support and a couple of smaller new features.
Qt Multimedia now supports rendering to multiple surfaces. In Qt GUI, image scaling and conversion routines are now multi-threaded for many use cases.
Qt Network now supports TLS 1.3 session tickets and configurable timeouts.
In Qt Core, QRunnable and QThreadPool can now work together with std::function and a new QFile::moveToTrash() method makes moving items to the trash can possible in a cross-platform way.
Finally, we've also added support for the native file dialog on Android.
More information
You can find a lot of information about Qt 5.15 and Qt 6 in the talks from Qt Virtual Tech Summit that we had last week.
Support period
Qt 5.15 is available now for all our users. For our open source users, it will be supported in the same way as other regular Qt releases until the release of Qt 6. For commercial customers, Qt 5.15 will be long-term-supported (LTS) for three years with regular bug fix releases beyond the release of Qt 6.
Remember that Qt 5.9 will stop receiving support by the 31st of May. While we have gone through great lengths to make sure Qt 5.15 will be easy to upgrade to, you still have the option to extend your support, should you need it. Watch Andy Shaw's very informative talk from Qt Virtual Tech Con to learn more about your options or contact us with any questions you may have.
Finally, I'd like to thank everybody who helped make this release possible and contributed to it.
I hope you will enjoy Qt 5.15!
Commenting for this post has ended.
Congrats on the new release, probably a great step forward in Qt development!Unfortunately as feared by many it might be the beginning of the end for Qt in many small open source projects. To be clear: I fully understand the need to have a solid financial ground for Qt. And I think as well that the new small business licences are a very fair option - for small businesses. For small non-profit, open source projects like us, there seems to be no place left. As the good offer that the small business licenses are, the two seats we need would wildly exceed what we get from donations etc. So as good as the offer is, it is simply no option. On the other side, we heaviliy depend on LTS releases. Moving from 5.6 to 5.9, and then from 5.9 to 5.12 took us weeks, for various reasons - changed behaviour of QML components, heavy bugs,... Also to be clear on this: I do not complain about the bugs. Qt is a very complex (and versatile) framework. Having bugs in there is natural. But it is also clear that we cannot switch Qt versions every 9 months. By that we would do hardly anything else than adopting new Qt versions - considering that we can spend only our free time on the project.We are very grateful for the opportunity to use Qt in our project. We do provide bug reports, test cases, ... but of course our return to the project is small. Still, I do not see how cutting of the small open source projects from the access to LTS versions benefit you. So please consider something like a 99€ tier for open source projects to solely get access to LTS releases, without any included support options. It would hardly require any efforts on your side and provide a future road for small projects. Without that I have no clue, how we could stick to Qt in the long run. Being forced away from Qt would be a heavy hit for our project, even more as I do not see any vital alternatives to Qt. Unlike many others, I am not very optimistic about an often proposed fork. It would probably become a loss for all parties. If your blog post about open source commitment was genuine, please find a way to offer small non-profits access to the LTS versions! Please!
I am in agreement with all of your message, but the 99€ tier suggestion. My (academic) open source project doesn't and will never get any donations. So, although your suggestion might work for you, it will not work for those of us who don't ask / can't ask for donations.
Alan, I can fully understand your objections. My suggestion is a compromise that I can think of, but yes, it won‘t work for every scenario as well. We are also putting much more money into our project than we could ever collect via donations. The 99€ would be certainly coming from my own pocket, but it would be an amount I could justify to put into my hobby. Obviously the best would be to have access to LTS as we had it before, but if that is not possible, we need to look out for other ways. The Qt people are doing this for a living, so if there is financial pressure, we could perhaps add small drops. Anyway, this is little more than spinning an idea, so we have to wait and see what happens. I simply hope there will eventually come up a solution, so we can stay with Qt.
Hi, Why 5.15.0 offline installer is still not available ? In all other releases the offline installer was available in the release date
From Qt 5.15 onwards the offline installer is provided only for commercial license holders.
According to whom? What bullshit. What if you have multiple systems to configure? Or systems that aren't online?
Is there a way to get rid of all deprecation warnings while remaining compatible with earlier versions of Qt? Setting QTNODEPRECATED_WARNINGS does not seem to work for deprecated enums like QString::SkipEmptyParts ... Also, is it possible to get rid of the onFoo runtime warnings ("Implicitly defined onFoo properties in Connections are deprecated") in QML? Having a few 100s of these all the time is not really funny without a way to disable them ...
About QML Connection: In 5.15.1, the warning will be under the "qt.qml.connections" logging category, so that can be used to suppress it. In 5.15.0, this is however not possible.
The post from felgo was published on planet.qt.io with info that they fixed webassembly bugs which was not fixed in Qt. What is the sense to take Qt codebase and fix bugs without merging them back to Qt?
Qt 5.12 LTS is available for MSVC 2015 64-bit, as well as MSVC 2017 32- and 64-bit while Qt 5.15 LTS is available for MSVC 2015 64-bit, MSVC 2019 32- and 64-bit, but not... MSVC 2017 32- and 64-bit? Why is that? If anything, I would have expected Qt 5.15 LTS to be available for MSVC 2017 64-bit rather than MSVC 2015 64-bit? Ok, one more reason for sticking with Qt 5.12 LTS then... 😕
MSVC 2017 and 2019 are binary compatible
Thanks Nicolás, I clearly wasn't aware of it. Is that mentioned somewhere in the Qt release?
It is documented by Microsoft: https://docs.microsoft.com/en-us/cpp/porting/binary-compat-2015-2017?view=vs-2019
Well t says "Here's an example: you can link an app compiled using the 2017 toolset to a static library compiled using 2019, if they're linked using the 2019 toolset." So you have to use 2019 linker to link your qt executale build with 2017 with the static qtwinmain.lib.
2017 and 2019 are binary compatible. You don't need a 2017 version.
I am using 5.12 2017 with 2019 just fine.
Thanks for the confirmation Hamish.
I do my main work on macOS for my Android / iOS apps. Also have some customers with W10, so have a W10 64 bit running in Parallels VM on top of macOS Qt Creator shares the project with macOS so normaly I only compile and build the project, then run windeployqt have MSVC2017 installed - am I right that I can still use MSVC2017 with Qt 5.15 ?
Well, that doesn't work the other way around - app compiled with vs2017 linked to qt 5.15 compiled with vs 2019 crashes at startup.
Then why not upgrade to 2019?
this isn't that easy - for instance, Travis doesn't have VS2019 yet, it should be installed manually. Plus, that requires all team to upgrade VS. Much easier solution is NOT to upgrade Qt.
Unfortunately macOS 10.12 also got deprecated. The minimum is now 10.13 which is not too old... :(
Where is the offline installer? I have multiple systems to configure. Not to mention that not all systems are online.
Come on, guys. That should be ready on release day.
From Qt 5.15 onwards the offline installer is provided only for commercial license holders.
This, combined with Qt Company's recent proposal to withhold updates from non-commercial users for a year, is a big STAY AWAY warning for anyone considering using Qt.
That is a duck move. And they all knew it when they announced it, because the post about the offering changes was outrageous. And so were all Qt management's replies on the development mailing list. All the more since 5.15 is the last version before the breaking changes of Qt6. At the very least they could have done it after Qt6. Despite I truly like working with Qt, I hope that they take a hard hit from this behavior. I've always been an advocate for Qt, but right now I just don't feel like recommending it, especially for open source projects! And that's kind of sad
Qt5 has improved a lot for the past years. It will take some time for Qt6 to catch up with Qt5 in terms of feature parity.
I hope that the right balance will be strike between Qt6 development and keeping Qt 5.15 LTS maintaned. In a way a properly maintained Qt 5.15 LTS makes a longer wait for Qt6 acceptable. And maybe a longer wait will result in a Qt6 that is better in any respect than Qt5.
I, for one, see myself using Qt 5.15 LTS in production for the next 12-18 months until Qt6.1 is released.
It's funny: "Qt 5.15 is the best and most stable release we've done in the Qt 5 series".
And get the bug, making the release unusable: https://bugreports.qt.io/browse/QTBUG-84545
I would like to point out that the latest source tarball, qt-everywhere-src-5.15.0.tar.xz, is corrupted. For example, qtbase\src\3rdparty\double-conversion\include\double-conversion has a file named "double-conv" instead of "double-conversion.h". There are multiple files in qtbase\src\platformsupport\fontdatabases\windows which have truncated file names and a couple of missing files. It appears that qt-everywhere-src-5.15.0.zip is fine.
Where is HeaderView documentation?
It looks like there is a mistake in the blog there, as there are distinct types for each orientation now:
What's about WebAssembly improvements in this release ?
I like to be at the forefront of what's happening, so it's nice to see the release of a new LTS. 👍
However, I really wish I could take advantage of this LTS until the next one gets released (and not only until the next version of Qt). I guess that’s what happens when you work in academia and on an open source project... 😕
Hello.
Qt Documentation says:
But this does not work in the release ( it worked in beta2 at least). Build fails in v8 build probably due to a 2017 compiler bug. Problem is similar to this nodejs issue https://github.com/nodejs/node-v8/issues/128 but the fix is not sufficient.
The Qt 5.15 Online Installer is getting stuck on "Retrieving meta information from remote repository... 1/2" on Windows 10. any workaround ? as I can see there is no offline installer.
Best is to try again a bit later. It may be due to temporary load in the download system. If not, please file a bug at bugreports.qt.io.
You are right, looks like it was the load on the system. It's working now thanks :)
Any plan to update the Ubuntu
qt5-defaultpackage to 5.15.0? It's currently on 5.9.5, and support for 5.9 stopped a few days ago.I have yet checked 5.15 but please focus more on mobile side of Qt than anything else. There are still serious graphical glitches that directly hampers user experience especially on the latest iOS model around the native virtual keyboard. Also, please look into Unreal Engine licensing model. As a solo founder, I personally don't care if you take a small percentage of revenue as long as your company offers everything to help my startup successful. $500 a year is still expensive from solo founder perspective while it maybe small for businesses that are getting traction later on, however if the business do get successful because of your unique C++ based fast performing cross-platform API that is guaranteed to be supported eternally, $4k a year from a successful company that may make millions profit a year is ridiculously small priced. I strongly suggest that you help startup companies successful, take more, and with money from them make far superior product than your competitors that will be maintained at the highest quality forever. I've been using your product for many years, but I can't get away thinking of abandoning Qt in favor of native API for mobile because I have to keep figure out a way to circumvent due to outdated support sometimes with no success at all which seriously affect user experience. Graphical glitches due to native virtual keyboard and cocoapods are especially serious problem because they are must-have for user experience and getting the latest AI tech into the app.
Hello I would like to know the exact vc++ ABI version that MSVC 2019 32 and 64 bit were build for both Qt 5.15.0 and 5.15.1 versions. The reason for this is a breaking ABI bug in the vtable solved in VS 2019 16.7.5 as described here: https://developercommunity.visualstudio.com/content/problem/1152794/with-vc-197-abi-change-in-vtable.html In case Qt versions were build with 16.7.0 - 16.7.4 this mean that they are not ABI compatible with previous versions, thus an update will be needed...
I really can't wait for someone to fork the 5.15 LTS branch and start backporting the fixes after the release of Qt6. I wonder how many devs will use 5.12 LTS until the very end. I for one won't even be touching 5.15 any time soon and I hope many do the same. Maybe that way you'll learn something...