Notify the main GUI thread upon receiving a close event instead of when
the windows is destroyed. Additionally there was a logic error in in
GuiReceiver::isLastWindow() that is corrected.
Fixes#6479 and #20822
displayOverlay doesn't disappear after timeout #27082Fixes#26555
### Expected Behaviour
An overlay should be displayed atop an image and then disappear after `delayms` has timed out, but it doesn't. Also, `displayStatusBar` doesn't appear to set any text on the window.
### Actual Behaviour
The overlay appears but doesn't disappear unless a mouse move event happens on the image.
### Changes
- Fixed the issue with `displayOverlay` not disappearing after the timeout.
### Checklist
- [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 the opencv_extra repository, if applicable.
- [ ] The feature is well documented, and sample code can be built with the project CMake.
- 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.
Fix compilation errors on GLES platforms
* Do not include glx.h when using GLES
GL/glx.h is included on all LINUX plattforms, which is wrong
for a number of reasons:
- GL_PERSPECTIVE_CORRECTION_HINT is defined in GL/gl.h, so we
want gl.h not glx.h, the latter just includes the former
- GL/gl.h is a Desktop GL header, and should not be included
on GLES plattforms
- GL/gl.h is already included via QtOpenGL ->
QtGui/qopengl.h on desktop plattforms
This fixes a problem when Qt is compiled with GLES, which
is often done on ARM platforms where desktop GL is not or
only poorly supported (e.g. slow due to emulation).
Fixes part of #9171.
* Only set GL_PERSPECTIVE_CORRECTION_HINT when GL version defines it
GL_PERSPECTIVE_CORRECTION_HINT does not exist in GLES 2.0/3.x,
and has been deprecated in OpenGL 3.0 core profiles.
Fixes part of #9171.
* removed C API in the following modules: photo, video, imgcodecs, videoio
* trying to fix various compile errors and warnings on Windows and Linux
* continue to fix compile errors and warnings
* continue to fix compile errors, warnings, as well as the test failures
* trying to resolve compile warnings on Android
* Update cap_dc1394_v2.cpp
fix warning from the new GCC
This offsets text brightness of pixel brightness values
by offsetting it by 127 to the curent pixel value.
The text is now readable even if pixels are black.
checks whether the window exists and is visible. On QT closing a window
merley hides it, so the common hack for checking whether a window exists
exists = cv2.getWindowProperty(.., 0) >= 0
does not work.
