Quick: Check fbo msaa related extensions via QtGui

GL_EXT_xxxx is not sufficient here. QOpenGLFunctions already has support
for the ANGLE and some other variants of the framebuffer multisample and
blit extensions, so use that instead of the manual checks.

Change-Id: I2d8e0850d3b0b9a9cfd9e55aa38adad07a0ba45d
Reviewed-by: Andy Nichols <andy.nichols@qt.io>

1 files changed, 4 insertions, 3 deletions

diff --git a/src/quick/scenegraph/qsgdefaultlayer.cpp b/src/quick/scenegraph/qsgdefaultlayer.cpp
index ad5b57ff83..78037a2fde 100644
--- a/src/quick/scenegraph/qsgdefaultlayer.cpp
+++ b/src/quick/scenegraph/qsgdefaultlayer.cpp
@@ -44,6 +44,7 @@
 
 #include <QtGui/QOpenGLFramebufferObject>
 #include <QtGui/QOpenGLFunctions>
+#include <QtGui/private/qopenglextensions_p.h>
 
 #include <QtQuick/private/qsgdepthstencilbuffer_p.h>
 
@@ -320,9 +321,9 @@ void QSGDefaultLayer::grab()
             if (m_context->openglContext()->format().samples() <= 1) {
                 m_multisampling = false;
             } else {
-                const QSet<QByteArray> extensions = m_context->openglContext()->extensions();
-                m_multisampling = extensions.contains(QByteArrayLiteral("GL_EXT_framebuffer_multisample"))
-                    && extensions.contains(QByteArrayLiteral("GL_EXT_framebuffer_blit"));
+                QOpenGLExtensions *e = static_cast<QOpenGLExtensions *>(funcs);
+                m_multisampling = e->hasOpenGLExtension(QOpenGLExtensions::FramebufferMultisample)
+                    && e->hasOpenGLExtension(QOpenGLExtensions::FramebufferBlit);
             }
             m_multisamplingChecked = true;
         }