Fix OpenGL mode in examples like composition

To avoid an incorrect offset for the native window, call create()
after createWindowContainer().

The mysterious -1 for the width and height are removed as well because
otherwise the GL window's size is clearly off by one.

Fixes: QTBUG-82195
Change-Id: I1a9cec62746fc110bfc4cd2e4fa111f621124638
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>
(cherry picked from commit d4548751b7b4183ab433df0927d59e3a6650625a)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

1 files changed, 5 insertions, 3 deletions

diff --git a/examples/widgets/painting/shared/arthurwidgets.cpp b/examples/widgets/painting/shared/arthurwidgets.cpp
index 40d712c9e3..7ad0fbac91 100644
--- a/examples/widgets/painting/shared/arthurwidgets.cpp
+++ b/examples/widgets/painting/shared/arthurwidgets.cpp
@@ -127,9 +127,11 @@ void ArthurFrame::createGlWindow()
     f.setStencilBufferSize(8);
     m_glWindow->setFormat(f);
     m_glWindow->setFlags(Qt::WindowTransparentForInput);
-    m_glWindow->resize(width() - 1, height() - 1);
-    m_glWindow->create();
+    m_glWindow->resize(width(), height());
     m_glWidget = QWidget::createWindowContainer(m_glWindow, this);
+    // create() must be called after createWindowContainer() otherwise
+    // an incorrect offsetting of the position will occur.
+    m_glWindow->create();
 }
 #endif
 
@@ -233,7 +235,7 @@ void ArthurFrame::resizeEvent(QResizeEvent *e)
 {
 #if QT_CONFIG(opengl)
     if (m_glWidget)
-        m_glWidget->setGeometry(0, 0, e->size().width()-1, e->size().height()-1);
+        m_glWidget->setGeometry(0, 0, e->size().width(), e->size().height());
 #endif
     QWidget::resizeEvent(e);
 }