Simplify computation of the invalidation rect for a frame.

third_party/WebKit/Source/web/WebPluginContainerImpl.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2014 Opera Software ASA. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 37 matching lines @@
 #include "core/frame/EventHandlerRegistry.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/LocalFrame.h"
 #include "core/frame/csp/ContentSecurityPolicy.h"
 #include "core/html/HTMLFormElement.h"
 #include "core/html/HTMLPlugInElement.h"
 #include "core/input/EventHandler.h"
 #include "core/layout/HitTestResult.h"
 #include "core/layout/LayoutBox.h"
 #include "core/layout/LayoutPart.h"
+#include "core/layout/LayoutView.h"
 #include "core/loader/FrameLoadRequest.h"
 #include "core/page/FocusController.h"
 #include "core/page/Page.h"
 #include "core/page/scrolling/ScrollingCoordinator.h"
 #include "core/paint/LayoutObjectDrawingRecorder.h"
 #include "core/paint/PaintLayer.h"
 #include "modules/plugins/PluginOcclusionSupport.h"
 #include "platform/HostWindow.h"
 #include "platform/KeyboardCodes.h"
 #include "platform/PlatformGestureEvent.h"
@@ skipping 869 matching lines @@
         return;
 
     LayoutBox* layoutObject = toLayoutBox(m_element->layoutObject());
     if (!layoutObject)
         return;
 
     layoutObject->invalidatePaintRectangle(LayoutRect(m_pendingInvalidationRect));
     m_pendingInvalidationRect = IntRect();
 }
 
+void WebPluginContainerImpl::computeClipRectsForPlugin(const HTMLFrameOwnerElement* ownerElement, IntRect& clippedAbsoluteRect, IntRect* unclippedIntAbsoluteRect) const
+{
+    ASSERT(ownerElement);
+
+    if (!ownerElement->layoutObject() || !ownerElement->layoutObject()->enclosingLayer()) {
+        clippedAbsoluteRect = IntRect();

[chrishtr, 2015/11/03 19:22:55]

I changed the code to just return an empty rect in scenarios where the plugin is
not attached to the layout tree properly. I think this will be fine.

[tommycli, 2015/11/03 20:10:22]

Acknowledged.

+        if (unclippedIntAbsoluteRect)
+            *unclippedIntAbsoluteRect = IntRect();
+
+        return;
+    }
+
+    LayoutView* rootView = m_element->document().view()->layoutView();
+    while (rootView->frame()->ownerLayoutObject())
+        rootView = rootView->frame()->ownerLayoutObject()->view();
+
+    const PaintLayer* enclosingLayer = ownerElement->layoutObject()->enclosingLayer();
+    LayoutRect unclippedAbsoluteRect = enclosingLayer->physicalBoundingBox(LayoutPoint());
+    enclosingLayer->layoutObject()->mapRectToPaintInvalidationBacking(rootView, unclippedAbsoluteRect, nullptr);

[chrishtr, 2015/11/03 19:22:55]

What this does: maps the box rect for the plugin container to the space of the
root view of the webpage, taking into account all transforms and clips along the
way. IOW it's the bounding box of the actual pixels the plugin can affect.

+
+    clippedAbsoluteRect = enclosingIntRect(unclippedAbsoluteRect);
+    clippedAbsoluteRect.intersect(rootView->frameView()->visibleContentRect());
+
+    if (unclippedIntAbsoluteRect)

[tommycli, 2015/11/03 20:10:22]

nit: Seems like you're doing the enclosingIntRect op twice. Can you just make a
copy from clippedAbsoluteRect to unclipped before you do the intersection?

[chrishtr, 2015/11/03 21:24:56]

Done.

+        *unclippedIntAbsoluteRect = enclosingIntRect(unclippedAbsoluteRect);
+}
+
 void WebPluginContainerImpl::calculateGeometry(IntRect& windowRect, IntRect& clipRect, IntRect& unobscuredRect, Vector<IntRect>& cutOutRects)
 {
     windowRect = toFrameView(parent())->contentsToRootFrame(frameRect());
 
     // Calculate a clip-rect so that we don't overlap the scrollbars, etc.
     clipRect = convertToContainingWindow(IntRect(0, 0, width(), height()));
     unobscuredRect = clipRect;
 
     // document().layoutView() can be 0 when we receive messages from the
     // plugins while we are destroying a frame.
     // FIXME: Can we just check m_element->document().isActive() ?
     if (m_element->layoutObject()->document().layoutView()) {
         // Take our element and get the clip rect from the enclosing layer and
         // frame view.
-        IntRect elementUnobscuredRect;
-        IntRect elementWindowClipRect = m_element->document().view()->clipRectsForFrameOwner(m_element, &elementUnobscuredRect);
-        clipRect.intersect(elementWindowClipRect);
-        unobscuredRect.intersect(elementUnobscuredRect);
+        IntRect unclippedAbsoluteRect;
+        IntRect clippedAbsoluteRect;
+        computeClipRectsForPlugin(m_element, clippedAbsoluteRect, &unclippedAbsoluteRect);
+        clipRect.intersect(clippedAbsoluteRect);
+        unobscuredRect.intersect(unclippedAbsoluteRect);
     }
 
     clipRect.move(-windowRect.x(), -windowRect.y());
     unobscuredRect.move(-windowRect.x(), -windowRect.y());
 
     getPluginOcclusions(m_element, this->parent(), frameRect(), cutOutRects);
     // Convert to the plugin position.
     for (size_t i = 0; i < cutOutRects.size(); i++)
         cutOutRects[i].move(-frameRect().x(), -frameRect().y());
 }
 
 } // namespace blink