Doc: replace deprecated references to QGLWidget

Remove references to the deprecated QGLWidget and replace it with
QOpenGLWidget.

Change-Id: Ia31df42ab61c25e9ce46f4491267d2c64910f55c
Reviewed-by: Paul Wicking <paul.wicking@qt.io>

examples/opengl/doc/src/2dpainting.qdoc

@@ -30,8 +30,8 @@
     \title 2D Painting Example
     \ingroup examples-widgets-opengl
 
-    \brief The 2D Painting example shows how QPainter and QGLWidget can be used
-    together to display accelerated 2D graphics on supported hardware.
+    \brief The 2D Painting example shows how QPainter and QOpenGLWidget can be
+    used together to display accelerated 2D graphics on supported hardware.
 
     \image 2dpainting-example.png
 
@@ -39,23 +39,23 @@
     paint devices provided by QPaintDevice subclasses, such as QWidget
     and QImage.
 
-    Since QGLWidget is a subclass of QWidget, it is possible
+    Since QOpenGLWidget is a subclass of QWidget, it is possible
     to reimplement its \l{QWidget::paintEvent()}{paintEvent()} and use
     QPainter to draw on the device, just as you would with a QWidget.
     The only difference is that the painting operations will be accelerated
     in hardware if it is supported by your system's OpenGL drivers.
 
     In this example, we perform the same painting operations on a
-    QWidget and a QGLWidget. The QWidget is shown with anti-aliasing
-    enabled, and the QGLWidget will also use anti-aliasing if the
+    QWidget and a QOpenGLWidget. The QWidget is shown with anti-aliasing
+    enabled, and the QOpenGLWidget will also use anti-aliasing if the
     required extensions are supported by your system's OpenGL driver.
 
     \section1 Overview
 
-    To be able to compare the results of painting onto a QGLWidget subclass
+    To be able to compare the results of painting onto a QOpenGLWidget subclass
     with native drawing in a QWidget subclass, we want to show both kinds
     of widget side by side. To do this, we derive subclasses of QWidget and
-    QGLWidget, using a separate \c Helper class to perform the same painting
+    QOpenGLWidget, using a separate \c Helper class to perform the same painting
     operations for each, and lay them out in a top-level widget, itself
     provided a the \c Window class.
 
@@ -63,7 +63,7 @@
 
     In this example, the painting operations are performed by a helper class.
     We do this because we want the same painting operations to be performed
-    for both our QWidget subclass and the QGLWidget subclass.
+    for both our QWidget subclass and the QOpenGLWidget subclass.
 
     The \c Helper class is minimal:
 
@@ -81,7 +81,7 @@
 
     The actual painting is performed in the \c paint() function. This takes
     a QPainter that has already been set up to paint onto a paint device
-    (either a QWidget or a QGLWidget), a QPaintEvent that provides information
+    (either a QWidget or a QOpenGLWidget), a QPaintEvent that provides information
     about the region to be painted, and a measure of the elapsed time (in
     milliseconds) since the paint device was last updated.
 
@@ -148,7 +148,7 @@
     \section1 GLWidget Class Definition
 
     The \c GLWidget class definition is basically the same as the \c Widget
-    class except that it is derived from QGLWidget.
+    class except that it is derived from QOpenGLWidget.
 
     \snippet 2dpainting/glwidget.h 0
 

examples/opengl/doc/src/cube.qdoc

@@ -47,7 +47,7 @@
     The example consist of two classes:
 
     \list
-    \li \c MainWidget extends QGLWidget and contains OpenGL ES 2.0
+    \li \c MainWidget extends QOpenGLWidget and contains OpenGL ES 2.0
         initialization and drawing and mouse and timer event handling
     \li \c GeometryEngine handles polygon geometries. Transfers polygon geometry
         to vertex buffer objects and draws geometries from vertex buffer objects.
@@ -92,7 +92,7 @@
 
     \section1 Loading Textures from Qt Resource Files
 
-    \c QGLWidget interface implements methods for loading textures from QImage to GL
+    \c QOpenGLWidget interface implements methods for loading textures from QImage to GL
     texture memory. We still need to use OpenGL provided functions for specifying
     the GL texture unit and configuring texture filtering options.
 

examples/widgets/doc/src/padnavigator.qdoc

@@ -545,7 +545,7 @@
     with OpenGL, but without OpenGL it avoids unnecessary re-scaling of the
     background pixmap.
     \li It sets render hints that increase rendering quality.
-    \li If OpenGL is supported, a QGLWidget viewport is assigned to the view.
+    \li If OpenGL is supported, a QOpenGLWidget viewport is assigned to the view.
     \endlist
 
     Finally, we start the state engine.

src/gui/painting/qpaintengine.cpp

@@ -158,7 +158,7 @@ QFont QTextItem::font() const
   X11 and \macos, it is the backend for painting on QImage and it is
   used as a fallback for paint engines that do not support a certain
   capability. In addition we provide QPaintEngine implementations for
-  OpenGL (accessible through QGLWidget) and printing (which allows using
+  OpenGL (accessible through QOpenGLWidget) and printing (which allows using
   QPainter to draw on a QPrinter object).
 
   If one wants to use QPainter to draw to a different backend,

src/widgets/doc/snippets/graphicsview.cpp

@@ -123,5 +123,9 @@ void CustomItem::mousePressEvent(QGraphicsSceneMouseEvent *event)
 
 //! [6]
 QGraphicsView view(&scene);
-view.setViewport(new QGLWidget(QGLFormat(QGL::SampleBuffers)));
+QOpenGLWidget *gl = new QOpenGLWidget();
+QSurfaceFormat format;
+format.setSamples(4);
+gl->setFormat(format);
+view.setViewport(gl);
 //! [6]

src/widgets/doc/src/graphicsview.qdoc

@@ -117,7 +117,7 @@
         of a scene. You can attach several views to the same scene, to provide
         several viewports into the same data set. The view widget is a scroll
         area, and provides scroll bars for navigating through large scenes. To
-        enable OpenGL support, you can set a QGLWidget as the viewport by
+        enable OpenGL support, you can set a QOpenGLWidget as the viewport by
         calling QGraphicsView::setViewport().
 
         \snippet graphicsview.cpp 1
@@ -436,10 +436,10 @@
 
       \section2 OpenGL Rendering
 
-        To enable OpenGL rendering, you simply set a new QGLWidget as the
+        To enable OpenGL rendering, you simply set a new QOpenGLWidget as the
         viewport of QGraphicsView by calling QGraphicsView::setViewport(). If
-        you want OpenGL with antialiasing, you need OpenGL sample buffer
-        support (see QGLFormat::sampleBuffers()).
+        you want OpenGL with antialiasing, you need to set a QSurfaceFormat
+        with the needed sample count (see QSurfaceFormat::setSamples()).
 
         Example:
 

src/widgets/graphicsview/qgraphicsproxywidget.cpp

@@ -581,7 +581,7 @@ QGraphicsProxyWidget::~QGraphicsProxyWidget()
 
     Note that widgets with the Qt::WA_PaintOnScreen widget attribute
     set and widgets that wrap an external application or controller
-    cannot be embedded. Examples are QGLWidget and QAxWidget.
+    cannot be embedded. Examples are QOpenGLWidget and QAxWidget.
 
     \sa widget()
 */

src/widgets/graphicsview/qgraphicsscene.cpp

@@ -2904,7 +2904,7 @@ QGraphicsSimpleTextItem *QGraphicsScene::addSimpleText(const QString &text, cons
 
     Note that widgets with the Qt::WA_PaintOnScreen widget attribute
     set and widgets that wrap an external application or controller
-    are not supported. Examples are QGLWidget and QAxWidget.
+    are not supported. Examples are QOpenGLWidget and QAxWidget.
 
     \sa addEllipse(), addLine(), addPixmap(), addPixmap(), addRect(),
     addText(), addSimpleText(), addItem()

src/widgets/graphicsview/qgraphicsview.cpp

@@ -89,8 +89,8 @@ static const int QGRAPHICSVIEW_PREALLOC_STYLE_OPTIONS = 503; // largest prime <
     By default, QGraphicsView provides a regular QWidget for the viewport
     widget. You can access this widget by calling viewport(), or you can
     replace it by calling setViewport(). To render using OpenGL, simply call
-    setViewport(new QGLWidget). QGraphicsView takes ownership of the viewport
-    widget.
+    setViewport(new QOpenGLWidget). QGraphicsView takes ownership of the
+    viewport widget.
 
     QGraphicsView supports affine transformations, using QTransform. You can
     either pass a matrix to setTransform(), or you can call one of the
@@ -159,8 +159,8 @@ static const int QGRAPHICSVIEW_PREALLOC_STYLE_OPTIONS = 503; // largest prime <
     fastest when QGraphicsView spends more time figuring out what to draw than
     it would spend drawing (e.g., when very many small items are repeatedly
     updated). This is the preferred update mode for viewports that do not
-    support partial updates, such as QGLWidget, and for viewports that need to
-    disable scroll optimization.
+    support partial updates, such as QOpenGLWidget, and for viewports that
+    need to disable scroll optimization.
 
     \value MinimalViewportUpdate QGraphicsView will determine the minimal
     viewport region that requires a redraw, minimizing the time spent drawing