macOS: Only enable layer-backed views on 10.14 if built against 10.14…

… SDK Instead of explicitly enabling layer-backing for Qt 5.12 on all macOS version, we follow the macOS default to enable it for 10.14 if the application binary was built against the 10.14 SDK. Aligning ourselves with Apple's switch to forced layer-backing means we have an easier story when it comes to supporting different runtime configurations. Fixes: QTBUG-71499 Change-Id: I34ee49b3daeb6ed8df444a3759d3573ebc9ea30f Reviewed-by: Tor Arne Vestbø <[email protected]>
zhangzhuo520 · Nov 9, 2018 · 2697148 · 2697148
1 parent d0e66df
commit 2697148
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Showing 2 changed files with 53 additions and 23 deletions.
diff --git a/src/plugins/platforms/cocoa/qnsview.mm b/src/plugins/platforms/cocoa/qnsview.mm
@@ -71,7 +71,7 @@ - (BOOL)isTransparentForUserInput;
 @end
 
 @interface QT_MANGLE_NAMESPACE(QNSView) (Drawing) <CALayerDelegate>
-- (BOOL)wantsLayerHelper;
+- (void)initDrawing;
 @end
 
 @interface QT_MANGLE_NAMESPACE(QNSViewMouseMoveHelper) : NSObject
@@ -152,19 +152,8 @@ - (instancetype)initWithCocoaWindow:(QCocoaWindow *)platformWindow
 
         self.focusRingType = NSFocusRingTypeNone;
         self.cursor = nil;
-        self.wantsLayer = [self wantsLayerHelper];
-
-        // Enable high-DPI OpenGL for retina displays. Enabling has the side
-        // effect that Cocoa will start calling glViewport(0, 0, width, height),
-        // overriding any glViewport calls in application code. This is usually not a
-        // problem, except if the application wants to have a "custom" viewport.
-        // (like the hellogl example)
-        if (m_platformWindow->window()->supportsOpenGL()) {
-            self.wantsBestResolutionOpenGLSurface = qt_mac_resolveOption(YES, m_platformWindow->window(),
-                "_q_mac_wantsBestResolutionOpenGLSurface", "QT_MAC_WANTS_BEST_RESOLUTION_OPENGL_SURFACE");
-            // See also QCocoaGLContext::makeCurrent for software renderer workarounds.
-        }
 
+        [self initDrawing];
         [self registerDragTypes];
 
         [[NSNotificationCenter defaultCenter] addObserver:self

diff --git a/src/plugins/platforms/cocoa/qnsview_drawing.mm b/src/plugins/platforms/cocoa/qnsview_drawing.mm
@@ -41,6 +41,24 @@
 
 @implementation QT_MANGLE_NAMESPACE(QNSView) (Drawing)
 
+- (void)initDrawing
+{
+    self.wantsLayer = [self layerExplicitlyRequested]
+        || [self shouldUseMetalLayer]
+        || [self layerEnabledByMacOS];
+
+    // Enable high-DPI OpenGL for retina displays. Enabling has the side
+    // effect that Cocoa will start calling glViewport(0, 0, width, height),
+    // overriding any glViewport calls in application code. This is usually not a
+    // problem, except if the application wants to have a "custom" viewport.
+    // (like the hellogl example)
+    if (m_platformWindow->window()->supportsOpenGL()) {
+        self.wantsBestResolutionOpenGLSurface = qt_mac_resolveOption(YES, m_platformWindow->window(),
+            "_q_mac_wantsBestResolutionOpenGLSurface", "QT_MAC_WANTS_BEST_RESOLUTION_OPENGL_SURFACE");
+        // See also QCocoaGLContext::makeCurrent for software renderer workarounds.
+    }
+}
+
 - (BOOL)isOpaque
 {
     if (!m_platformWindow)
@@ -71,23 +89,38 @@ - (void)drawRect:(NSRect)dirtyRect
     m_platformWindow->handleExposeEvent(exposedRegion);
 }
 
-- (BOOL)shouldUseMetalLayer
+- (BOOL)layerEnabledByMacOS
 {
-    // MetalSurface needs a layer, and so does VulkanSurface (via MoltenVK)
-    QSurface::SurfaceType surfaceType = m_platformWindow->window()->surfaceType();
-    return surfaceType == QWindow::MetalSurface || surfaceType == QWindow::VulkanSurface;
+    // AppKit has its own logic for this, but if we rely on that, our layers are created
+    // by AppKit at a point where we've already set up other parts of the platform plugin
+    // based on the presence of layers or not. Once we've rewritten these parts to support
+    // dynamically picking up layer enablement we can let AppKit do its thing.
+    return QMacVersion::buildSDK() >= QOperatingSystemVersion::MacOSMojave
+        && QMacVersion::currentRuntime() >= QOperatingSystemVersion::MacOSMojave;
 }
 
-- (BOOL)wantsLayerHelper
+- (BOOL)layerExplicitlyRequested
 {
-    Q_ASSERT(m_platformWindow);
+    static bool wantsLayer = [&]() {
+        int wantsLayer = qt_mac_resolveOption(-1, m_platformWindow->window(),
+            "_q_mac_wantsLayer", "QT_MAC_WANTS_LAYER");
 
-    bool wantsLayer = qt_mac_resolveOption(true, m_platformWindow->window(),
-        "_q_mac_wantsLayer", "QT_MAC_WANTS_LAYER");
+        if (wantsLayer != -1 && [self layerEnabledByMacOS]) {
+            qCWarning(lcQpaDrawing) << "Layer-backing can not be explicitly controlled on 10.14 when built against the 10.14 SDK";
+            return true;
+        }
 
-    bool layerForSurfaceType = [self shouldUseMetalLayer];
+        return wantsLayer == 1;
+    }();
 
-    return wantsLayer || layerForSurfaceType;
+    return wantsLayer;
+}
+
+- (BOOL)shouldUseMetalLayer
+{
+    // MetalSurface needs a layer, and so does VulkanSurface (via MoltenVK)
+    QSurface::SurfaceType surfaceType = m_platformWindow->window()->surfaceType();
+    return surfaceType == QWindow::MetalSurface || surfaceType == QWindow::VulkanSurface;
 }
 
 - (CALayer *)makeBackingLayer
@@ -115,6 +148,14 @@ - (CALayer *)makeBackingLayer
     return [super makeBackingLayer];
 }
 
+- (void)setLayer:(CALayer *)layer
+{
+    qCDebug(lcQpaDrawing) << "Making" << self << "layer-backed with" << layer
+        << "due to being" << ([self layerExplicitlyRequested] ? "explicitly requested"
+            : [self shouldUseMetalLayer] ? "needed by surface type" : "enabled by macOS");
+    [super setLayer:layer];
+}
+
 - (NSViewLayerContentsRedrawPolicy)layerContentsRedrawPolicy
 {
     // We need to set this explicitly since the super implementation