Fix the qt demo on Windows when building with Qt6. (#1971)

* Fix the qt demo on Windows when building with Qt6. * Fix the wrong display size.
Tencent · Dec 7, 2023 · 120fd5c · 120fd5c
1 parent 525ec2d
commit 120fd5c
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Showing 2 changed files with 45 additions and 43 deletions.
diff --git a/qt/src/PAGView.cpp b/qt/src/PAGView.cpp
@@ -68,72 +68,75 @@ PAGView::~PAGView() {
   QMetaObject::invokeMethod(renderThread, "shutDown", Qt::QueuedConnection);
   renderThread->wait();
   delete renderThread;
+  delete shareContext;
   delete pagPlayer;
 }
 
-void PAGView::onCreateDrawable(QOpenGLContext* context) {
-  if (drawable == nullptr) {
-    drawable = GPUDrawable::MakeFrom(this, context);
-    drawable->moveToThread(renderThread);
-  }
-}
-
-#if (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
-
-void PAGView::geometryChange(const QRectF& newGeometry, const QRectF& oldGeometry) {
-  if (newGeometry == oldGeometry) {
-    return;
-  }
-  QQuickItem::geometryChange(newGeometry, oldGeometry);
-  onSizeChanged();
-}
-
 void PAGView::handleWindowChanged(QQuickWindow* window) {
   if (drawable != nullptr || window == nullptr) {
     return;
   }
+#if (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
   auto openglContext = reinterpret_cast<QOpenGLContext*>(window->rendererInterface()->getResource(
       window, QSGRendererInterface::OpenGLContextResource));
+#else
+  auto openglContext = window->openglContext();
+#endif
   if (openglContext != nullptr) {
-    onCreateDrawable(openglContext);
+    QMetaObject::invokeMethod(this, "createDrawable");
   } else {
-    connect(window, SIGNAL(sceneGraphInitialized()), this, SLOT(handleOpenglContextCreated()));
+    connect(window, SIGNAL(sceneGraphInitialized()), this, SLOT(handleOpenglContextCreated()),
+            Qt::DirectConnection);
   }
 }
 
 void PAGView::handleOpenglContextCreated() {
   disconnect(window(), SIGNAL(sceneGraphInitialized()), this, SLOT(handleOpenglContextCreated()));
-  auto openglContext = reinterpret_cast<QOpenGLContext*>(window()->rendererInterface()->getResource(
+#if (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
+  auto context = reinterpret_cast<QOpenGLContext*>(window()->rendererInterface()->getResource(
       window(), QSGRendererInterface::OpenGLContextResource));
-  onCreateDrawable(openglContext);
+#else
+  auto context = window()->openglContext();
+#endif
+  if (shareContext == nullptr) {
+    // Creating a context that shares with a context that is current on another thread is not safe,
+    // some drivers on windows can reject this.
+    // We work this around by introducing an additional context that lives on the same thread as the
+    // SceneGraph's context, shares with it, but is never current. The main thread's context will
+    // then share with this extra context.
+    shareContext = new QOpenGLContext();
+    shareContext->setFormat(context->format());
+    shareContext->setShareContext(context);
+    shareContext->create();
+  }
+  QMetaObject::invokeMethod(this, "createDrawable");
 }
 
-#else
+void PAGView::createDrawable() {
+  if (drawable == nullptr) {
+    drawable = GPUDrawable::MakeFrom(this, shareContext);
+    drawable->moveToThread(renderThread);
+  }
+}
 
-void PAGView::geometryChanged(const QRectF& newGeometry, const QRectF& oldGeometry) {
+#if (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
+
+void PAGView::geometryChange(const QRectF& newGeometry, const QRectF& oldGeometry) {
   if (newGeometry == oldGeometry) {
     return;
   }
-  QQuickItem::geometryChanged(newGeometry, oldGeometry);
+  QQuickItem::geometryChange(newGeometry, oldGeometry);
   onSizeChanged();
 }
 
-void PAGView::handleWindowChanged(QQuickWindow* window) {
-  if (drawable != nullptr || window == nullptr) {
+#else
+
+void PAGView::geometryChanged(const QRectF& newGeometry, const QRectF& oldGeometry) {
+  if (newGeometry == oldGeometry) {
     return;
   }
-  if (window->openglContext() != nullptr) {
-    onCreateDrawable(window->openglContext());
-  } else {
-    connect(window, SIGNAL(openglContextCreated(QOpenGLContext*)), this,
-            SLOT(handleOpenglContextCreated(QOpenGLContext*)));
-  }
-}
-
-void PAGView::handleOpenglContextCreated(QOpenGLContext* context) {
-  disconnect(window(), SIGNAL(openglContextCreated(QOpenGLContext*)), this,
-             SLOT(handleOpenglContextCreated(QOpenGLContext*)));
-  onCreateDrawable(context);
+  QQuickItem::geometryChanged(newGeometry, oldGeometry);
+  onSizeChanged();
 }
 
 #endif
@@ -151,6 +154,7 @@ QSGNode* PAGView::updatePaintNode(QSGNode* oldNode, UpdatePaintNodeData*) {
     auto pagSurface = PAGSurface::MakeFrom(drawable);
     pagPlayer->setSurface(pagSurface);
     lastDevicePixelRatio = window()->devicePixelRatio();
+    onSizeChanged();
     renderThread->start();
   }
 

diff --git a/qt/src/PAGView.h b/qt/src/PAGView.h
@@ -51,21 +51,19 @@ class PAGView : public QQuickItem {
   QString filePath = "";
   PAGPlayer* pagPlayer = new PAGPlayer();
   RenderThread* renderThread = nullptr;
+  QOpenGLContext* shareContext = nullptr;
   std::shared_ptr<GPUDrawable> drawable = nullptr;
 
   void onSizeChanged();
-  void onCreateDrawable(QOpenGLContext* context);
 
   Q_SLOT
   void handleWindowChanged(QQuickWindow* window);
 
-#if (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
   Q_SLOT
   void handleOpenglContextCreated();
-#else
+
   Q_SLOT
-  void handleOpenglContextCreated(QOpenGLContext* context);
-#endif
+  void createDrawable();
 
   friend class RenderThread;
 };