macOS: Treat default swapInterval (-1) as vsync-enabled display-link

Change-Id: I6d3d241d3813bfac36155ad219d4a338cb1ef6f7 Reviewed-by: Tor Arne Vestbø <[email protected]>
pkubaj · Feb 11, 2019 · 17e5158 · 17e5158
1 parent 21e25ff
commit 17e5158
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Showing 3 changed files with 12 additions and 6 deletions.
diff --git a/src/plugins/platforms/cocoa/qcocoascreen.mm b/src/plugins/platforms/cocoa/qcocoascreen.mm
@@ -330,7 +330,7 @@ void flushOutput() {
         auto windows = QGuiApplication::allWindows();
         for (int i = 0; i < windows.size(); ++i) {
             QWindow *window = windows.at(i);
-            QPlatformWindow *platformWindow = window->handle();
+            auto *platformWindow = static_cast<QCocoaWindow*>(window->handle());
             if (!platformWindow)
                 continue;
 
@@ -341,7 +341,7 @@ void flushOutput() {
                 continue;
 
             // Skip windows that are not doing update requests via display link
-            if (!(window->format().swapInterval() > 0))
+            if (!platformWindow->updatesWithDisplayLink())
                 continue;
 
             platformWindow->deliverUpdateRequest();

diff --git a/src/plugins/platforms/cocoa/qcocoawindow.h b/src/plugins/platforms/cocoa/qcocoawindow.h
@@ -129,6 +129,7 @@ class QCocoaWindow : public QObject, public QPlatformWindow
     bool isForeignWindow() const override;
 
     void requestUpdate() override;
+    bool updatesWithDisplayLink() const;
     void deliverUpdateRequest() override;
 
     void requestActivateWindow() override;

diff --git a/src/plugins/platforms/cocoa/qcocoawindow.mm b/src/plugins/platforms/cocoa/qcocoawindow.mm
@@ -1473,18 +1473,23 @@ Posted whenever an NSView object that has attached surfaces (that is,
 
 void QCocoaWindow::requestUpdate()
 {
-    const int swapInterval = format().swapInterval();
-    qCDebug(lcQpaDrawing) << "QCocoaWindow::requestUpdate" << window() << "swapInterval" << swapInterval;
+    qCDebug(lcQpaDrawing) << "QCocoaWindow::requestUpdate" << window()
+        << "using" << (updatesWithDisplayLink() ? "display-link" : "timer");
 
-    if (swapInterval > 0) {
-        // Vsync is enabled, deliver via CVDisplayLink
+    if (updatesWithDisplayLink()) {
         static_cast<QCocoaScreen *>(screen())->requestUpdate();
     } else {
         // Fall back to the un-throttled timer-based callback
         QPlatformWindow::requestUpdate();
     }
 }
 
+bool QCocoaWindow::updatesWithDisplayLink() const
+{
+    // Update via CVDisplayLink if Vsync is enabled
+    return format().swapInterval() != 0;
+}
+
 void QCocoaWindow::deliverUpdateRequest()
 {
     // Don't send update requests for views that need display, as the update