Bug 711168 - Implement the compositor protocol for OMTC. r=cjones

widget/xpwidgets/nsBaseWidget.cpp

@@ -38,6 +38,8 @@
 
 #include "mozilla/Util.h"
 
+#include "mozilla/layers/CompositorChild.h"
+#include "mozilla/layers/CompositorParent.h"
 #include "nsBaseWidget.h"
 #include "nsDeviceContext.h"
 #include "nsCOMPtr.h"
@@ -55,6 +57,7 @@
 #include "nsIXULRuntime.h"
 #include "nsIGfxInfo.h"
 #include "npapi.h"
+#include "base/thread.h"
 
 #ifdef DEBUG
 #include "nsIObserver.h"
@@ -70,6 +73,8 @@ static PRInt32 gNumWidgets;
 
 using namespace mozilla::layers;
 using namespace mozilla;
+using base::Thread;
+using mozilla::ipc::AsyncChannel;
 
 nsIContent* nsBaseWidget::mLastRollup = nsnull;
 
@@ -104,6 +109,7 @@ nsBaseWidget::nsBaseWidget()
 , mEventCallback(nsnull)
 , mViewCallback(nsnull)
 , mContext(nsnull)
+, mCompositorThread(nsnull)
 , mCursor(eCursor_standard)
 , mWindowType(eWindowType_child)
 , mBorderStyle(eBorderStyle_none)
@@ -142,6 +148,12 @@ nsBaseWidget::~nsBaseWidget()
 
   if (mLayerManager) {
     mLayerManager->Destroy();
+    mLayerManager = nsnull;
+  }
+
+  if (mCompositorChild) {
+    mCompositorChild->Destroy();
+    delete mCompositorThread;
   }
 
 #ifdef NOISY_WIDGET_LEAKS
@@ -814,6 +826,38 @@ nsBaseWidget::GetShouldAccelerate()
   return mUseAcceleratedRendering;
 }
 
+void nsBaseWidget::CreateCompositor()
+{
+  mCompositorParent = new CompositorParent(this);
+  mCompositorThread = new Thread("CompositorThread");
+  if (mCompositorThread->Start()) {
+    LayerManager* lm = CreateBasicLayerManager();
+    MessageLoop *childMessageLoop = mCompositorThread->message_loop();
+    mCompositorChild = new CompositorChild(lm);
+    AsyncChannel *parentChannel = mCompositorParent->GetIPCChannel();
+    AsyncChannel::Side childSide = mozilla::ipc::AsyncChannel::Child;
+    mCompositorChild->Open(parentChannel, childMessageLoop, childSide);
+    PLayersChild* shadowManager =
+      mCompositorChild->SendPLayersConstructor(LayerManager::LAYERS_OPENGL);
+
+    if (shadowManager) {
+      ShadowLayerForwarder* lf = lm->AsShadowForwarder();
+      if (!lf) {
+        delete lm;
+        mCompositorChild = nsnull;
+      }
+      lf->SetShadowManager(shadowManager);
+      lf->SetParentBackendType(LayerManager::LAYERS_OPENGL);
+
+      mLayerManager = lm;
+    } else {
+      NS_WARNING("fail to construct LayersChild");
+      delete lm;
+      mCompositorChild = nsnull;
+    }
+  }
+}
+
 LayerManager* nsBaseWidget::GetLayerManager(PLayersChild* aShadowManager,
                                             LayersBackend aBackendHint,
                                             LayerManagerPersistence aPersistence,
@@ -824,16 +868,29 @@ LayerManager* nsBaseWidget::GetLayerManager(PLayersChild* aShadowManager,
     mUseAcceleratedRendering = GetShouldAccelerate();
 
     if (mUseAcceleratedRendering) {
-      nsRefPtr<LayerManagerOGL> layerManager = new LayerManagerOGL(this);
-      /**
-       * XXX - On several OSes initialization is expected to fail for now.
-       * If we'd get a none-basic layer manager they'd crash. This is ok though
-       * since on those platforms it will fail. Anyone implementing new
-       * platforms on LayerManagerOGL should ensure their widget is able to
-       * deal with it though!
-       */
-      if (layerManager->Initialize()) {
-        mLayerManager = layerManager;
+
+      // Try to use an async compositor first, if possible
+      bool useCompositor =
+        Preferences::GetBool("layers.offmainthreadcomposition.enabled", false);
+      if (useCompositor) {
+        // e10s uses the parameter to pass in the shadow manager from the TabChild
+        // so we don't expect to see it there since this doesn't support e10s.
+        NS_ASSERTION(aShadowManager == nsnull, "Async Compositor not supported with e10s");
+        CreateCompositor();
+      }
+
+      if (!mLayerManager) {
+        nsRefPtr<LayerManagerOGL> layerManager = new LayerManagerOGL(this);
+        /**
+         * XXX - On several OSes initialization is expected to fail for now.
+         * If we'd get a non-basic layer manager they'd crash. This is ok though
+         * since on those platforms it will fail. Anyone implementing new
+         * platforms on LayerManagerOGL should ensure their widget is able to
+         * deal with it though!
+         */
+        if (layerManager->Initialize()) {
+          mLayerManager = layerManager;
+        }
       }
     }
     if (!mLayerManager) {