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Everything development. From desktop and mobile to cloud. Games, tools, 3rd party libraries. Everything.
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  • This is where all the desktop OS and general Qt questions belong.
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    N
    Thanks, solution found, similar to what you are suggesting. I dug a bit further into Qt docs and found the entry for setPointsConfiguration, which takes data in the form of QHash<int, QHash<QXYSeries::PointConfiguration, QVariant>> So my new code for setting the colors looks like: QHash<int, QHash<QXYSeries::PointConfiguration, QVariant>> ptsConfig; QList<BrthPosnPlots>::iterator brthItr = m_brthPosns.begin(); MultiLineSeries *thisSrs = GetLineSeries(srs); QList<QPointF> srspts = thisSrs->points(); quint32 ctSrs = srspts.size(); if ((ctSrs < 1)) return; qsizetype bpos; for (brthItr = m_brthPosns.begin(); brthItr != m_brthPosns.end(); brthItr++) { if ((*brthItr).GetEEPos() > ctSrs) continue; if (((*brthItr).GetEIPos() > 1) && ((*brthItr).GetEEPos() > (*brthItr).GetEIPos() + 5)) { for (bpos = (*brthItr).GetEIPos(); bpos < (*brthItr).GetEEPos(); bpos++) { ptsConfig.insert_or_assign(bpos, conf); // thisSrs->setPointConfiguration(bpos, conf); } } } if (!ptsConfig.isEmpty()) { thisSrs->setPointsConfiguration(ptsConfig); } The speedup is truly amazing! From over 2 sec down to < 20 msec for this method. Thanks to all for feedback and tips.
  • Looking for The Bling Thing(tm)? Post here!
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    Pl45m4P
    @bogong said in Qt6 ApplicationWindow vs Windows - what is better to use ?: There are two components 'Window' and 'ApplicationWindow'. What is better to use with Qt 6? I would say it's comparable to QWidget vs. QMainWindow The latter with its integrated QMenuBar, QToolBar and QStatusBar support, whereas the former provides a more "plain" Widget (or QML Control / Window in your case)
  • The forum for developing everything embedded: Linux, WinCE, Symbian, MeeGo... you name it.
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    In my case I had to: qunsetenv("QT_QPA_EGLFS_HIDECURSOR"); For framebuffer it would be: qunsetenv("QT_QPA_FB_HIDECURSOR"); Yes this is an ancient post, but it still comes up top in google.
  • This is a discussion space for

    • for audio / video playback and recording
    • media formats and codecs
    • camera and screen sharing functionality
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    V
    I have been having this same issue with my Bluetooth headset not being detected
  • Have a question about Qt Creator, our cross-platform IDE, or any of the other tools? Ask here!
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    R
    I have solved this by defining everything under the "build" folder in the different *.pro files. It seems that if a subproject is configured individually, i.e. outside of the SUBDIRS project, whatever configuration is overridden by the SUBDIRS main project configuration. I put the "TEMPLATE=lib" subproject files into the "3rd_party" folder. The only drawback is then that the different Makefiles.* and .qmake.stash files used in building the libraries are also generated in that folder which is under source code management. However, these can be ignored by the SCM by applying the corresponding settings necessary for ignoring certain files.
  • Your Qt just doesn't want to build? Your compiler can't find the libs? Here's where you find comfort and understanding. And help.
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    Grit ClefG
    However I continuously received that error on libraries not belonging to Qt itself. For example, /usr/lib/qt6/plugins/platforminputcontexts/libfcitx5platforminputcontextplugin.so doesn't have RPATH information, either. I'd like to ask if there's a way to limit the generic Qt deploy tool to certain Qt libraries?
  • What can we say - we like games. And you can use Qt to write some. Questions? Ask here.
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    8Observer88
    It looks like you are running into a classic RHI (Rendering Hardware Interface) mismatch. Even though the performance feels snappy, those warnings are red flags that your current environment is missing the specific shader translations needed for the OpenGL backend. Here’s the breakdown of what is actually happening under the hood: 1. The Shader Version Gap The error versions tried: QList(130, 120) tells us that your application is looking for older, "baked" GLSL shader code (OpenGL 3.0/2.1 era). However, the only shader found in your binary is Version(300), which corresponds to OpenGL ES 3.0. What you're missing: Your application was likely compiled/packaged with shaders targeting modern mobile or DirectX/Vulkan backends, but the runtime is falling back to a legacy OpenGL path that doesn't have the corresponding "blobs" to talk to the GPU. 2. Why it "Works" on the Newer Machine The newer machine likely has a more robust driver set or a different default RHI priority. DirectX 11 vs. OpenGL: On Windows, Qt and similar frameworks perform significantly better on DirectX because they can use the ANGLE layer, which translates OpenGL calls to DirectX. The "Speed" Illusion: If the scene is still fast, your system might be successfully falling back to a software rasterizer or a partial hardware acceleration path, but you'll eventually hit a "Black Screen" or a crash when the app tries to call a specific graphics pipeline that failed to build. Comparison of Backends Feature OpenGL (Legacy) DirectX 11 Vulkan / Metal Stability Lower on Windows High (Windows native) High (Modern) Shader Format GLSL HLSL SPIR-V Compatibility Hit-or-miss drivers Best for Windows Best for Cross-platform How to Fix This You likely need to force the application to use a backend that matches its baked shaders. Try one of the following: Force the RHI: Set an environment variable before launching the app to see if it clears the warning: QT_RHI_BACKEND=d3d11 (For Windows) QT_RHI_BACKEND=vulkan (If supported) Update Drivers: Even if the machine is "older," ensure the GPU drivers support OpenGL 3.3+. Check Shader Baking: If you are the developer, ensure your qsb (Qt Shader Baker) settings include the desktop GLSL versions (--glsl "130,120,100") and not just the ES versions. Note: The "Failed to build graphics pipeline" error is the most critical. It means certain effects, materials, or lighting calculations simply won't render, even if the rest of the UI seems to be moving. Would you like me to show you how to check which OpenGL versions your current GPU drivers actually support? P.S. Sorry, but my answer above was generated with Gemini. I think it can be usefull.
  • Discussions and questions on QtWebEngine
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    D
    I have the same problem in FC42. QtWebEngine seems to be a complete disaster. Tried to compile 6.8.2 for FC42 but it failed after many hours of compiling.
  • You're using Qt with other languages than C++, eh? Post here!
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    PedromixP
    [image: bdbda216-f9b8-469f-b90d-0e6b273560de.png] New version QtJambi 6.10.2 is available now 🎉. For all who want to create smart UIs🚀 in Java or Kotlin based upon the latest Qt release. https://www.qtjambi.io/
  • For discussion and questions about Qt for Python (PySide & Shiboken)

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    SGaistS
    Hi and welcome to devnet, Something like that likely exists but it's not part of the default set of Qt components. One thing you could do is explore KDE's extensive set of applications. There might be something there that you could leverage for your project.
  • Specific issues when using Qt for WebAssembly

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    Axel SpoerlA
    Hi, please format your code, using the </> code formatting tags. It makes just so much easier to read. WASM is a bit stricter than other OSes when it comes to deployment and embedded resources. Most certainly adding RESOURCE_PREFIX /qt/qml right above the imports will solve the problem.
  • Discussions and questions about Qt Quick Ultralite and using Qt on microcontrollers in general

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    I am working on a Qt for MCUs application and currently using OTF font files with the Static font engine. The font quality is good with OTF, but internal flash usage becomes very high. When I use FMP fonts, flash usage is low, but some glyphs do not render properly. Any guidance on the correct approach to move OTF font storage to external memory would be very helpful. Thank you.
  • Combining Qt with 3rd party libraries or components? Ask here!
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    B
    What is the recommended way to create custom scale labels for QKnob? What I am trying to achieve is something like this: 1 0.5 0.2 0.1 50 20 10 5 2 1 0.5 etc. I gather I need to overload QwtRoundScaleDraw and QwtRoundScaleDraw::label() but I am sure where to define the custom scale.
  • The forum for discussing the Qt Digital Advertising Platform

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    @nayka Can I use QtDigitalAdvertising on PC applications? Or is it only allowed for use on Android or iOS mobile devices?
  • For discussion and questions about Qt Insight

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    jsulmJ
    @Alejandro_qt_ Here is an example how to build qtbase module: https://stackoverflow.com/questions/50022325/building-qt-module-from-source