1 files changed, 45 insertions, 36 deletions

diff --git a/src/quickwidgets/qquickwidget.cpp b/src/quickwidgets/qquickwidget.cpp
index 8d93bf389b..ef6c174b88 100644
--- a/src/quickwidgets/qquickwidget.cpp
+++ b/src/quickwidgets/qquickwidget.cpp
@@ -200,6 +200,26 @@ void QQuickWidgetPrivate::itemGeometryChanged(QQuickItem *resizeItem, const QRec
     QQuickItemChangeListener::itemGeometryChanged(resizeItem, newGeometry, oldGeometry);
 }
 
+void QQuickWidgetPrivate::render(bool needsSync)
+{
+    context->makeCurrent(offscreenSurface);
+
+    if (needsSync) {
+        renderControl->polishItems();
+        renderControl->sync();
+    }
+
+    renderControl->render();
+    context->functions()->glFlush();
+
+    if (resolvedFbo) {
+        QRect rect(QPoint(0, 0), fbo->size());
+        QOpenGLFramebufferObject::blitFramebuffer(resolvedFbo, rect, fbo, rect);
+    }
+
+    context->doneCurrent();
+}
+
 void QQuickWidgetPrivate::renderSceneGraph()
 {
     Q_Q(QQuickWidget);
@@ -215,19 +235,8 @@ void QQuickWidgetPrivate::renderSceneGraph()
     }
 
     Q_ASSERT(offscreenSurface);
-    context->makeCurrent(offscreenSurface);
-    renderControl->polishItems();
-    renderControl->sync();
-    renderControl->render();
-    context->functions()->glFlush();
-
-    if (resolvedFbo) {
-        QRect rect(QPoint(0, 0), fbo->size());
-        QOpenGLFramebufferObject::blitFramebuffer(resolvedFbo, rect, fbo, rect);
-    }
-
-    context->doneCurrent();
-    q->update();
+    render(true);
+    q->update(); // schedule composition
 }
 
 QImage QQuickWidgetPrivate::grabFramebuffer()
@@ -294,6 +303,11 @@ QImage QQuickWidgetPrivate::grabFramebuffer()
     some of the benefits of threaded rendering, for example \l Animator classes and vsync driven
     animations, will not be available.
 
+    \note Avoid calling winId() on a QQuickWidget. This function triggers the creation of
+    a native window, resulting in reduced performance and possibly rendering glitches. The
+    entire purpose of QQuickWidget is to render Quick scenes without a separate native
+    window, hence making it a native widget should always be avoided.
+
     \section1 Limitations
 
     Putting other widgets underneath and making the QQuickWidget transparent will not lead
@@ -937,29 +951,14 @@ void QQuickWidget::resizeEvent(QResizeEvent *e)
         return;
     }
 
-    context->makeCurrent(d->offscreenSurface);
-
-    if (needsSync) {
-        d->renderControl->polishItems();
-        d->renderControl->sync();
-    }
-
-    d->renderControl->render();
-    context->functions()->glFlush();
-
-    if (d->resolvedFbo) {
-        QRect rect(QPoint(0, 0), d->fbo->size());
-        QOpenGLFramebufferObject::blitFramebuffer(d->resolvedFbo, rect, d->fbo, rect);
-    }
-
-    context->doneCurrent();
+    d->render(needsSync);
 }
 
 /*! \reimp */
 void QQuickWidget::keyPressEvent(QKeyEvent *e)
 {
     Q_D(QQuickWidget);
-    Q_QUICK_PROFILE(addEvent<QQuickProfiler::Key>());
+    Q_QUICK_INPUT_PROFILE(addEvent<QQuickProfiler::Key>());
 
     QCoreApplication::sendEvent(d->offscreenWindow, e);
 }
@@ -968,7 +967,7 @@ void QQuickWidget::keyPressEvent(QKeyEvent *e)
 void QQuickWidget::keyReleaseEvent(QKeyEvent *e)
 {
     Q_D(QQuickWidget);
-    Q_QUICK_PROFILE(addEvent<QQuickProfiler::Key>());
+    Q_QUICK_INPUT_PROFILE(addEvent<QQuickProfiler::Key>());
 
     QCoreApplication::sendEvent(d->offscreenWindow, e);
 }
@@ -977,7 +976,7 @@ void QQuickWidget::keyReleaseEvent(QKeyEvent *e)
 void QQuickWidget::mouseMoveEvent(QMouseEvent *e)
 {
     Q_D(QQuickWidget);
-    Q_QUICK_PROFILE(addEvent<QQuickProfiler::Mouse>());
+    Q_QUICK_INPUT_PROFILE(addEvent<QQuickProfiler::Mouse>());
 
     // Use the constructor taking localPos and screenPos. That puts localPos into the
     // event's localPos and windowPos, and screenPos into the event's screenPos. This way
@@ -992,7 +991,7 @@ void QQuickWidget::mouseMoveEvent(QMouseEvent *e)
 void QQuickWidget::mouseDoubleClickEvent(QMouseEvent *e)
 {
     Q_D(QQuickWidget);
-    Q_QUICK_PROFILE(addEvent<QQuickProfiler::Mouse>());
+    Q_QUICK_INPUT_PROFILE(addEvent<QQuickProfiler::Mouse>());
 
     // As the second mouse press is suppressed in widget windows we emulate it here for QML.
     // See QTBUG-25831
@@ -1025,7 +1024,7 @@ void QQuickWidget::hideEvent(QHideEvent *)
 void QQuickWidget::mousePressEvent(QMouseEvent *e)
 {
     Q_D(QQuickWidget);
-    Q_QUICK_PROFILE(addEvent<QQuickProfiler::Mouse>());
+    Q_QUICK_INPUT_PROFILE(addEvent<QQuickProfiler::Mouse>());
 
     QMouseEvent mappedEvent(e->type(), e->localPos(), e->screenPos(), e->button(), e->buttons(), e->modifiers());
     QCoreApplication::sendEvent(d->offscreenWindow, &mappedEvent);
@@ -1036,7 +1035,7 @@ void QQuickWidget::mousePressEvent(QMouseEvent *e)
 void QQuickWidget::mouseReleaseEvent(QMouseEvent *e)
 {
     Q_D(QQuickWidget);
-    Q_QUICK_PROFILE(addEvent<QQuickProfiler::Mouse>());
+    Q_QUICK_INPUT_PROFILE(addEvent<QQuickProfiler::Mouse>());
 
     QMouseEvent mappedEvent(e->type(), e->localPos(), e->screenPos(), e->button(), e->buttons(), e->modifiers());
     QCoreApplication::sendEvent(d->offscreenWindow, &mappedEvent);
@@ -1048,7 +1047,7 @@ void QQuickWidget::mouseReleaseEvent(QMouseEvent *e)
 void QQuickWidget::wheelEvent(QWheelEvent *e)
 {
     Q_D(QQuickWidget);
-    Q_QUICK_PROFILE(addEvent<QQuickProfiler::Mouse>());
+    Q_QUICK_INPUT_PROFILE(addEvent<QQuickProfiler::Mouse>());
 
     // Wheel events only have local and global positions, no need to map.
     QCoreApplication::sendEvent(d->offscreenWindow, e);
@@ -1099,6 +1098,16 @@ bool QQuickWidget::event(QEvent *e)
     case QEvent::WindowChangeInternal:
         d->handleWindowChange();
         break;
+
+    case QEvent::ScreenChangeInternal:
+        if (d->fbo) {
+            // This will check the size taking the devicePixelRatio into account
+            // and recreate if needed.
+            createFramebufferObject();
+            d->render(true);
+        }
+        break;
+
     default:
         break;
     }