1 files changed, 14 insertions, 13 deletions

diff --git a/src/quick/scenegraph/qsgrenderloop.cpp b/src/quick/scenegraph/qsgrenderloop.cpp
index ac4c315ccb..443afb00ac 100644
--- a/src/quick/scenegraph/qsgrenderloop.cpp
+++ b/src/quick/scenegraph/qsgrenderloop.cpp
@@ -371,7 +371,7 @@ void QSGGuiThreadRenderLoop::windowDestroyed(QQuickWindow *window)
     d->cleanupNodesOnShutdown();
 
 #if QT_CONFIG(quick_shadereffect)
-    QSGRhiShaderEffectNode::cleanupMaterialTypeCache();
+    QSGRhiShaderEffectNode::cleanupMaterialTypeCache(window);
 #endif
 
     if (m_windows.size() == 0) {
@@ -442,7 +442,7 @@ bool QSGGuiThreadRenderLoop::ensureRhi(QQuickWindow *window, WindowData &data)
 {
     QQuickWindowPrivate *cd = QQuickWindowPrivate::get(window);
     QSGRhiSupport *rhiSupport = QSGRhiSupport::instance();
-    bool current = false;
+    bool ok = rhi != nullptr;
 
     if (!rhi) {
         // This block below handles both the initial QRhi initialization and
@@ -463,7 +463,9 @@ bool QSGGuiThreadRenderLoop::ensureRhi(QQuickWindow *window, WindowData &data)
 
             data.rhiDeviceLost = false;
 
-            current = true;
+            ok = true;
+            // We need to guarantee that sceneGraphInitialized is
+            // emitted with a context current, if running with OpenGL.
             rhi->makeThreadLocalNativeContextCurrent();
 
             // The sample count cannot vary between windows as we use the same
@@ -483,16 +485,8 @@ bool QSGGuiThreadRenderLoop::ensureRhi(QQuickWindow *window, WindowData &data)
                 data.rhiDoomed = true;
                 handleContextCreationFailure(window);
             }
-            // otherwise no error, will retry on a subsequent rendering attempt
+            // otherwise no error, just return false so that we will retry on a subsequent rendering attempt
         }
-    } else {
-        current = true;
-        // With the rhi making the (OpenGL) context current serves only one
-        // purpose: to enable external OpenGL rendering connected to one of
-        // the QQuickWindow signals (beforeSynchronizing, beforeRendering,
-        // etc.) to function like it did on the direct OpenGL path. For our
-        // own rendering this call would not be necessary.
-        rhi->makeThreadLocalNativeContextCurrent();
     }
 
     if (rhi && !cd->swapchain) {
@@ -541,7 +535,7 @@ bool QSGGuiThreadRenderLoop::ensureRhi(QQuickWindow *window, WindowData &data)
         window->installEventFilter(this);
     }
 
-    return current;
+    return ok;
 }
 
 void QSGGuiThreadRenderLoop::renderWindow(QQuickWindow *window)
@@ -655,6 +649,12 @@ void QSGGuiThreadRenderLoop::renderWindow(QQuickWindow *window)
         }
     }
 
+    // Enable external OpenGL rendering connected to one of the
+    // QQuickWindow signals (beforeSynchronizing, beforeRendering,
+    // etc.) to function like it did on the direct OpenGL path,
+    // i.e. ensure there is a context current, just in case.
+    rhi->makeThreadLocalNativeContextCurrent();
+
     cd->syncSceneGraph();
     if (lastDirtyWindow)
         rc->endSync();
@@ -765,6 +765,7 @@ QImage QSGGuiThreadRenderLoop::grab(QQuickWindow *window)
     // renderWindow() so one cannot get to grab() without having done at least
     // one on-screen frame.
     cd->rhi->beginFrame(cd->swapchain);
+    rhi->makeThreadLocalNativeContextCurrent(); // for custom GL rendering before/during/after sync
     cd->syncSceneGraph();
     cd->renderSceneGraph(window->size());
     QImage image = QSGRhiSupport::instance()->grabAndBlockInCurrentFrame(rhi, cd->swapchain->currentFrameCommandBuffer());