Qt Development
Everything development. From desktop and mobile to cloud. Games, tools, 3rd party libraries. Everything.
144.0kTopics722.0kPosts
Subcategories
- 84kTopics459kPostsUsing qmake in Qt Creator 18.0.2, I'm investigating the different possibilities of setting up the global "Default Build Directory" in Qt Creator settings (in "Preferences/Build & Run") to facilitate doing out-of-source builds. I see many wildcards I can use, such as "%{BuildConfig:Name}" and "%{Project:Name}", but I can't find anything that would allow inserting the contents of the qmake TEMPLATE.The project consists of one main SUBDIRS project file, calling this "MyApp.pro", an "App.pro" with TEMPLATE=app and two subprojects, each of which have TEMPLATE=lib. These "lib" subprojects are responsible for generating one static library each. The source code is organized like this -- the folders marked with "SCM" are under source code management, and any build folders or binary files, should be placed outside of these: MyApp ├── 3rd_party <== SCM 'REPO_THIRD' │ ├── lib_1 │ │ └── src │ └── lib_2 │ └── src └── App <== SCM 'REPO_APP' ├── include ├── qrc ├── src ├── translations └── ui App.pro MyApp.pro Lib_1.pro Lib_2.proI know that it is unusual to have all of the .pro files in the same folder as the main project, but this works out well. I can get MyApp.pro to build the application correctly with this as my default build in "Preferences":../build/%{Project:Name}/%{Qt:Version}/%{BuildConfig:Name}This results in the following shadowed build folder after opening the main "MyApp" project file in Qt Creator when I click on "Projects" in the task bar:MyApp/build/MyApp/6.10.2/Debugusing a kit for Qt 6.10.2, for example, building in Debug mode. I create a "lib" folder parallel to the "build" folder in the library projects by setting DESTDIR and TARGET appropriately.Since I would eventually like to migrate the qmake build to CMake (or at least offer a CMake build as an alternative to the qmake build), the folder structure should end up looking something like this: MyApp ├── build │ ├── appbuild │ │ ├── Debug │ │ └── Release │ └── libbuild │ ├── Debug │ └── Release ├── 3rd_party <== SCM 'REPO_THIRD' │ ├── Lib_1 │ │ └── src │ └── Lib_2 │ └── src └── App <== SCM 'REPO_APP'(etc.)That way, the "build" subfolder can be created in the traditional (?) CMake fashion either in Creator or by doing cmake -B build from the project directory.But what is the trick for getting the strings "appbuild" and "libbuild" into the "Default Build Directory" setting? I don't want to have to manually edit the shadow build directory for each configuration. Ideally, one should be able to write %{Project:Template} to achieve this, but i couldn't find anything.
- 20kTopics78kPosts
Mobile and Embedded
The forum for developing everything embedded: Linux, WinCE, Symbian, MeeGo... you name it.14kTopics63kPostsWithplayer.source = "gstreamer-pipeline:v4l2src device=/dev/video4 ! capsfilter caps=video/x-raw,width=720,height=480,framerate=30/1"Segfault1 format_cmp_func gstv4l2object.c 1328 0xffffcf22524c2 g_slist_insert_sorted_real gslist.c 862 0xfffff61430703 g_slist_insert_sorted gslist.c 913 0xfffff6143a5c4 gst_v4l2_object_fill_format_list gstv4l2object.c 1376 0xffffcf2243a45 gst_v4l2_object_get_format_list gstv4l2object.c 1425 0xffffcf2248746 gst_v4l2_object_probe_caps gstv4l2object.c 5446 0xffffcf2304147 gst_v4l2_object_get_caps gstv4l2object.c 5635 0xffffcf230a748 gst_base_src_default_query gstbasesrc.c 1373 0xffffe16fae8c9 gst_pad_query gstpad.c 4252 0xffffe15c0d2810 gst_pad_query_caps gstutils.c 3117 0xffffe160af8c11 gst_v4l2src_negotiate gstv4l2src.c 788 0xffffcf23b58412 gst_base_src_negotiate_unlocked gstbasesrc.c 3502 0xffffe16f543c13 gst_base_src_loop gstbasesrc.c 2920 0xffffe16f778014 gst_task_func gsttask.c 399 0xffffe15fb35415 g_thread_pool_thread_proxy gthreadpool.c 336 0xfffff615325c16 g_thread_proxy gthread.c 890 0xfffff6152b4017 start_thread pthread_create.c 448 0xfffff656085c18 thread_start clone3.S 76 0xfffff65c40ccQt Multimedia
This is a discussion space for
- for audio / video playback and recording
- media formats and codecs
- camera and screen sharing functionality
51Topics222PostsQt Creator and other tools
Have a question about Qt Creator, our cross-platform IDE, or any of the other tools? Ask here!8kTopics36kPostsInstallation and Deployment
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.10kTopics51kPostsHowever 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?Game Development
What can we say - we like games. And you can use Qt to write some. Questions? Ask here.875Topics4kPostsIt 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 GapThe 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 MachineThe 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 BackendsFeatureOpenGL (Legacy)DirectX 11Vulkan / MetalStabilityLower on WindowsHigh (Windows native)High (Modern)Shader FormatGLSLHLSLSPIR-VCompatibilityHit-or-miss driversBest for WindowsBest for Cross-platformHow to Fix ThisYou 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.- 1kTopics4kPosts
- 2Topics16Posts
- 869Topics3kPosts
- 3kTopics15kPosts
- 465Topics2kPosts
Qt for MCUs
Discussions and questions about Qt Quick Ultralite and using Qt on microcontrollers in general
156Topics475PostsI 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.- 1kTopics6kPosts
- 16Topics39Posts
- 11Topics20Posts
About accessing the bug report system
WatchingIgnoringScheduledPinnedLockedMoved Unsolved5Votes1Posts42ViewsNo one has repliedForum general guide
WatchingIgnoringScheduledPinnedLockedMovedguidanceforumgeneral13Votes24Posts32kViews
