Use surfaceSize as this will always be valid

This fixes an issue when resizing a Scene3D that is inside
a QQuickWidget to ensure that it has something rendered in
each frame.

Fixes: QTBUG-83095
Change-Id: Ic6c8b1b2efd0757f9f88768aafb331c4c1a1f9f2
Reviewed-by: Mike Krus <mike.krus@kdab.com>
(cherry picked from commit 2e3607aa120324f60832ca1cd42aaeaf22cc148d)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/src/plugins/renderers/opengl/graphicshelpers/submissioncontext.cpp b/src/plugins/renderers/opengl/graphicshelpers/submissioncontext.cpp
index 34f31f23f..86f0af505 100644
--- a/src/plugins/renderers/opengl/graphicshelpers/submissioncontext.cpp
+++ b/src/plugins/renderers/opengl/graphicshelpers/submissioncontext.cpp
@@ -604,7 +604,7 @@ QSize SubmissionContext::renderTargetSize(const QSize &surfaceSize) const
                 return renderTargetSize;
         }
     } else {
-        renderTargetSize = m_surface->size();
+        renderTargetSize = surfaceSize;
         if (m_surface->surfaceClass() == QSurface::Window) {
             const float dpr = static_cast<QWindow *>(m_surface)->devicePixelRatio();
             renderTargetSize *= dpr;