Make QOpenGLWidget public

QOpenGLWidget is now public.

In addition Qt::WA_AlwaysStackOnTop is introduced to support the
special case of semi-transparent QOpenGLWidget or QQuickWidget on
top of regular widgets.

hellogl_es2 becomes the qopenglwidget example. This example performs
painting both via QPainter and native GL commands and has the OpenGL
widget combined with other, normal widgets.

The widget stack receives some changes when it comes to renderToTexture
widgets like QQuickWidget and QOpenGLWidget. Calling update() will now
result in a paint event, which is essential for QOpenGLWidget since we
want it to behave like a regular widget. The dirty region handling is
extended specially for such widgets due to performance reasons.
(an OpenGL content update must not result in any backingstore painting,
and is thus handled as a different kind of dirtiness)

[ChangeLog] Added QOpenGLWidget. This widget serves as a replacement for QGLWidget.

Task-number: QTBUG-36899
Task-number: QTBUG-40086
Change-Id: Ibf7f82fea99b39edfffd2fc088e7e0eadbca25cf
Reviewed-by: Paul Olav Tvete <paul.tvete@digia.com>

1 files changed, 6 insertions, 1 deletions

diff --git a/src/opengl/qgl.cpp b/src/opengl/qgl.cpp
index d1417cfde5..30e55592c5 100644
--- a/src/opengl/qgl.cpp
+++ b/src/opengl/qgl.cpp
@@ -3612,6 +3612,11 @@ void QGLContext::doneCurrent()
     except that you have the choice between using QPainter and
     standard OpenGL rendering commands.
 
+    \note This class is part of the legacy \l {Qt OpenGL} module and,
+    like the other \c QGL classes, should be avoided in the new
+    applications. Instead, starting from Qt 5.4, prefer using
+    QOpenGLWidget and the \c QOpenGL classes.
+
     QGLWidget provides three convenient virtual functions that you can
     reimplement in your subclass to perform the typical OpenGL tasks:
 
@@ -3807,7 +3812,7 @@ void QGLContext::doneCurrent()
     \e{OpenGL is a trademark of Silicon Graphics, Inc. in the United States and other
     countries.}
 
-    \sa QGLPixelBuffer, {Hello GL Example}, {2D Painting Example}, {Overpainting Example},
+    \sa QOpenGLWidget, QGLPixelBuffer, {Hello GL Example}, {2D Painting Example}, {Overpainting Example},
         {Grabber Example}
 */