Support OpenGL GTK3 New API #25822Fixes#20001
GSoC2024 Project
### Pull Request Readiness Checklist
See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request
- [x] I agree to contribute to the project under Apache 2 License.
- [x] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
- [x] The PR is proposed to the proper branch
- [x] There is a reference to the original bug report and related work
- [ ] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
Patch to opencv_extra has the same branch name.
- [ ] The feature is well documented and sample code can be built with the project CMake
Highgui backend on top of Framebuffer #25661
### Pull Request Readiness Checklist
See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request
- [ x] I agree to contribute to the project under Apache 2 License.
- [ x] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
- [ x] The PR is proposed to the proper branch
- [ ] There is a reference to the original bug report and related work
- [ x] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
Patch to opencv_extra has the same branch name.
- [ x] The feature is well documented and sample code can be built with the project CMake
Environment variables used:
OPENCV_UI_BACKEND - you need to add the value “FB”
OPENCV_UI_PRIORITY_FB - requires priority indication
OPENCV_HIGHGUI_FB_MODE={FB|XVFB|EMU} - mode of using Framebuffer (default "FB")
- FB - Linux Framebuffer
- XVFB - virtual Framebuffer
- EMU - emulation (images are not displayed)
OPENCV_HIGHGUI_FB_DEVICE (FRAMEBUFFER) - path to the Framebuffer file (default "/dev/fb0").
Examples of using:
sudo OPENCV_UI_BACKEND=FB ./opencv_test_highgui
sudo OPENCV_UI_PRIORITY_FB=1111 ./opencv_test_highgui
OPENCV_UI_BACKEND=FB OPENCV_HIGHGUI_FB_MODE=EMU ./opencv_test_highgui
sudo OPENCV_UI_BACKEND=FB OPENCV_HIGHGUI_FB_MODE=FB ./opencv_test_highgui
export DISPLAY=:99
Xvfb $DISPLAY -screen 0 1024x768x24 -fbdir /tmp/ -f /tmp/user.xvfb.auth&
sudo -u sipeed XAUTHORITY=/tmp/user.xvfb.auth x11vnc -display $DISPLAY -listen localhost&
DISPLAY=:0 gvncviewer localhost&
FRAMEBUFFER=/tmp/Xvfb_screen0 OPENCV_UI_BACKEND=FB OPENCV_HIGHGUI_FB_MODE=XVFB ./opencv_test_highgui
-enable using -DWITH_WAYLAND=ON
-adapted from https://github.com/pfpacket/opencv-wayland
-using xdg_shell stable protocol
-overrides HAVE_QT if HAVE_WAYLAND and WITH_WAYLAND are set
Signed-off-by: Joel Winarske <joel.winarske@gmail.com>
Co-authored-by: Ryo Munakata <afpacket@gmail.com>
The Qt backend directly calls some OpenGL functions (glClear, glHint,
glViewport), but since OCV 4.5.5 the GL libraries are no longer part
of the global extra dependencies. When linking with "-Wl,--no-undefined"
this causes linker errors:
`opencv-4.5.5/modules/highgui/src/window_QT.cpp:3307: undefined reference to `glClear'`
Fixes: #21346
Related issues: #21299
- QGLWidget changed to QOpenGLWidget in window_QT.h for Qt6 using
typedef OpenCVQtWidgetBase for handling Qt version
- Implement Qt6/OpenGL functionality in window_QT.cpp
- Swap QGLWidget:: function calls for OpenCVQtWidgetBase:: function calls
- QGLWidget::updateGL deprecated, swap to QOpenGLWidget::update for Qt6
- Add preprocessor definition to detect Qt6 -- HAVE_QT6
- Add OpenGLWidgets to qdeps list in highgui CMakeLists.txt
- find_package CMake command added for locating Qt module OpenGLWidgets
- Added check that Qt6::OpenGLWidgets component is found. Shut off Qt-openGL functionality if not found.
The objective is to:
*Reduce greatly the number of lines of code in the Java codes;
*Make it easy for Java users to add a trackbar and show the results;
*Get the code more similar between C++, Java and Python, making the tutorials more uniform.
