Bug 944938 - Create an APZCTM controller for the compositor parent on Mac with APZ enabled. r=smichaud

widget/cocoa/nsChildView.h

@@ -95,6 +95,7 @@ class RectTextureImage;
 namespace mozilla {
 namespace layers {
 class GLManager;
+class APZCTreeManager;
 }
 }
 
@@ -437,6 +438,7 @@ class nsChildView : public nsBaseWidget,
 {
 private:
   typedef nsBaseWidget Inherited;
+  typedef mozilla::layers::APZCTreeManager APZCTreeManager;
 
 public:
                           nsChildView();
@@ -572,6 +574,7 @@ public:
   already_AddRefed<mozilla::a11y::Accessible> GetDocumentAccessible();
 #endif
 
+  virtual CompositorParent* NewCompositorParent(int aSurfaceWidth, int aSurfaceHeight);
   virtual void CreateCompositor();
   virtual gfxASurface* GetThebesSurface();
   virtual void PrepareWindowEffects() MOZ_OVERRIDE;
@@ -627,6 +630,8 @@ public:
   void EndRemoteDrawing() MOZ_OVERRIDE;
   void CleanupRemoteDrawing() MOZ_OVERRIDE;
 
+  APZCTreeManager* APZCTM() { return mAPZCTreeManager; }
+
 protected:
 
   void              ReportMoveEvent();
@@ -727,6 +732,8 @@ protected:
   // surface to the screen using an OpenGL context.
   nsAutoPtr<GLPresenter> mGLPresenter;
 
+  nsRefPtr<APZCTreeManager> mAPZCTreeManager;
+
   static uint32_t sLastInputEventCount;
 
   void ReleaseTitlebarCGContext();

widget/cocoa/nsChildView.mm

@@ -65,11 +65,13 @@
 #include "GLUploadHelpers.h"
 #include "ScopedGLHelpers.h"
 #include "HeapCopyOfStackArray.h"
+#include "mozilla/layers/APZCTreeManager.h"
 #include "mozilla/layers/GLManager.h"
 #include "mozilla/layers/CompositorOGL.h"
 #include "mozilla/layers/CompositorParent.h"
 #include "mozilla/layers/BasicCompositor.h"
 #include "gfxUtils.h"
+#include "gfxPrefs.h"
 #include "mozilla/gfx/2D.h"
 #include "mozilla/gfx/BorrowedContext.h"
 #ifdef ACCESSIBILITY
@@ -137,6 +139,8 @@ bool gUserCancelledDrag = false;
 
 uint32_t nsChildView::sLastInputEventCount = 0;
 
+static uint32_t gNumberOfWidgetsNeedingEventThread = 0;
+
 @interface ChildView(Private)
 
 // sets up our view, attaching it to its owning gecko view
@@ -190,6 +194,8 @@ uint32_t nsChildView::sLastInputEventCount = 0;
 - (id<mozAccessible>)accessible;
 #endif
 
+- (APZCTreeManager*)apzctm;
+
 - (BOOL)inactiveWindowAcceptsMouseEvent:(NSEvent*)aEvent;
 
 @end
@@ -485,6 +491,13 @@ nsChildView::~nsChildView()
 
   DestroyCompositor();
 
+  if (mAPZCTreeManager) {
+    gNumberOfWidgetsNeedingEventThread--;
+    if (gNumberOfWidgetsNeedingEventThread == 0) {
+      [EventThreadRunner stop];
+    }
+  }
+
   // An nsChildView object that was in use can be destroyed without Destroy()
   // ever being called on it.  So we also need to do a quick, safe cleanup
   // here (it's too late to just call Destroy(), which can cause crashes).
@@ -2098,6 +2111,27 @@ nsChildView::CreateCompositor()
   }
 }
 
+CompositorParent*
+nsChildView::NewCompositorParent(int aSurfaceWidth, int aSurfaceHeight)
+{
+  CompositorParent *compositor = nsBaseWidget::NewCompositorParent(aSurfaceWidth, aSurfaceHeight);
+
+  if (gfxPrefs::AsyncPanZoomEnabled()) {
+    uint64_t rootLayerTreeId = compositor->RootLayerTreeId();
+    nsRefPtr<APZCTMController> controller = new APZCTMController();
+    CompositorParent::SetControllerForLayerTree(rootLayerTreeId, controller);
+    mAPZCTreeManager = CompositorParent::GetAPZCTreeManager(rootLayerTreeId);
+    mAPZCTreeManager->SetDPI(GetDPI());
+
+    if (gNumberOfWidgetsNeedingEventThread == 0) {
+      [EventThreadRunner start];
+    }
+    gNumberOfWidgetsNeedingEventThread++;
+  }
+
+  return compositor;
+}
+
 gfxASurface*
 nsChildView::GetThebesSurface()
 {
@@ -5772,6 +5806,11 @@ static int32_t RoundUp(double aDouble)
   return NSDragOperationNone;
 }
 
+- (APZCTreeManager*)apzctm
+{
+  return mGeckoChild ? mGeckoChild->APZCTM() : nullptr;
+}
+
 // This is a utility function used by NSView drag event methods
 // to send events. It contains all of the logic needed for Gecko
 // dragging to work. Returns the appropriate cocoa drag operation code.