QOpenGLWidget sample - fix detaching OCCT viewer inside QDockWidget into top-level window

Author: gkv311

occt-qt-tools/OcctQtTools.cpp

@@ -135,6 +135,10 @@ void OcctQtTools::qtGlPlatformSetup()
   }
 #endif
 
+  // request Qt to share resources between OpenGL contexts like QOpenGLWidget and QQuickWidget;
+  // allows detaching OCCT 3D Viewer widget inside QDockWidget into new top-level window
+  QCoreApplication::setAttribute(Qt::AA_ShareOpenGLContexts);
+
 /*#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
   // workaround for some bugs in Qt5
   OSD_Environment aQGlyph("QT_ENABLE_GLYPH_CACHE_WORKAROUND");

occt-qwidget/main.cpp

@@ -179,10 +179,6 @@ int main(int theNbArgs, char** theArgVec)
   QCoreApplication::setOrganizationName("OpenCASCADE");
   QCoreApplication::setApplicationVersion(OCC_VERSION_STRING_EXT);
 
-  // request OpenGL-compatible surface from Qt
-  const QSurfaceFormat aGlFormat = OcctQtTools::qtGlSurfaceFormat();
-  QSurfaceFormat::setDefaultFormat(aGlFormat);
-
   MyMainWindow aMainWindow;
   aMainWindow.resize(aMainWindow.sizeHint());
   aMainWindow.show();