Insert pinch zoom virtual viewport layers to graphics layer tree.

Source/WebKit/chromium/src/WebViewImpl.cpp

 /*
  * Copyright (C) 2011, 2012 Google Inc. 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.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 39 matching lines @@
 #include "AutofillPopupMenuClient.h"
 #include "CSSValueKeywords.h"
 #include "CompositionUnderlineVectorBuilder.h"
 #include "ContextFeaturesClientImpl.h"
 #include "DeviceOrientationClientProxy.h"
 #include "GeolocationClientProxy.h"
 #include "GraphicsLayerFactoryChromium.h"
 #include "HTMLNames.h"
 #include "LinkHighlight.h"
 #include "PageWidgetDelegate.h"
+#include "PinchViewports.h"
 #include "PopupContainer.h"
 #include "PrerendererClientImpl.h"
 #include "SpeechInputClientImpl.h"
 #include "SpeechRecognitionClientProxy.h"
 #include "TextFieldDecoratorImpl.h"
 #include "ValidationMessageClientImpl.h"
 #include "ViewportAnchor.h"
 #include "WebAccessibilityObject.h"
 #include "WebActiveWheelFlingParameters.h"
 #include "WebAutofillClient.h"
@@ skipping 71 matching lines @@
 #include "core/platform/graphics/Extensions3D.h"
 #include "core/platform/graphics/FontCache.h"
 #include "core/platform/graphics/FontDescription.h"
 #include "core/platform/graphics/GraphicsContext.h"
 #include "core/platform/graphics/GraphicsContext3D.h"
 #include "core/platform/graphics/Image.h"
 #include "core/platform/graphics/ImageBuffer.h"
 #include "core/platform/graphics/chromium/LayerPainterChromium.h"
 #include "core/platform/graphics/gpu/SharedGraphicsContext3D.h"
 #include "core/platform/network/ResourceHandle.h"
-#include "core/rendering/RenderLayerCompositor.h"
 #include "core/rendering/RenderView.h"
 #include "core/rendering/RenderWidget.h"
 #include "core/rendering/TextAutosizer.h"
 #include "modules/geolocation/GeolocationController.h"
 #include "weborigin/SchemeRegistry.h"
 #include "weborigin/SecurityOrigin.h"
 #include "weborigin/SecurityPolicy.h"
 #include "painting/ContinuousPainter.h"
 
 #if ENABLE(DEFAULT_RENDER_THEME)
@@ skipping 1442 matching lines @@
     }
 
     // Set the fixed layout size from the viewport constraints before resizing.
     updatePageDefinedPageScaleConstraints(mainFrameImpl()->frame()->document()->viewportArguments());
 
     WebDevToolsAgentPrivate* agentPrivate = devToolsAgentPrivate();
     if (agentPrivate)
         agentPrivate->webViewResized(newSize);
     if (!agentPrivate || !agentPrivate->metricsOverridden()) {
         WebFrameImpl* webFrame = mainFrameImpl();
-        if (webFrame->frameView())
+        if (webFrame->frameView()) {
             webFrame->frameView()->resize(m_size);
+            if (m_pinchViewports)
+                m_pinchViewports->setViewportSize(FloatSize(m_size.width, m_size.height));
+        }
     }
 
     if (settings()->viewportEnabled()) {
         // Relayout immediately to recalculate the minimum scale limit.
         if (view->needsLayout())
             view->layout();
 
         if (shouldAnchorAndRescaleViewport) {
             float viewportWidthRatio = static_cast<float>(newSize.width) / oldSize.width;
             float contentsWidthRatio = static_cast<float>(contentsSize().width()) / oldContentsWidth;
@@ skipping 2173 matching lines @@
 
 bool WebViewImpl::allowsAcceleratedCompositing()
 {
     return !m_compositorCreationFailed;
 }
 
 void WebViewImpl::setRootGraphicsLayer(GraphicsLayer* layer)
 {
     suppressInvalidations(true);
 
-    m_rootGraphicsLayer = layer;
-    m_rootLayer = layer ? layer->platformLayer() : 0;
+    if (page()->settings()->pinchVirtualViewportEnabled() && !m_pinchViewports)
+        m_pinchViewports = PinchViewports::create(this);

[jamesr, 2013/06/14 20:55:46]

do you need to tear the pinch viewports down when leaving compositing mode?

[wjmaclean, 2013/06/17 17:45:27]

I don't *think* so, though I could be convinced otherwise. Here's my reasoning:

1) I assume "leaving compositing mode" corresponds to (layer == 0) in
WebViewImpl::setRootGraphicsLayer(). In this case, any existing viewport layers
are disconnected from the tree, and so do nothing.

2) When the root graphics layer changes (and typically the RenderLayerCompositor
behind it), we disconnect and then re-connect the viewport layers. Since they
don't rely on anything outside PinchViewports (e.g. they don't rely on RLC to be
a client), this re-use should be OK.

In practice building the viewport layer structure once and re-using it seems to
have worked fine, and I am unaware if any reason why it shouldn't be ok. But,
I'm also OK with tearing it down and rebuilding each time if that seems safer.

+
+    if (m_pinchViewports) {
+        m_pinchViewports->setOverflowControlsHostLayer(layer);
+        if (layer) {
+            m_rootGraphicsLayer = m_pinchViewports->rootGraphicsLayer();
+            m_rootLayer = m_pinchViewports->rootGraphicsLayer()->platformLayer();
+        } else {
+            m_rootGraphicsLayer = 0;
+            m_rootLayer = 0;
+        }
+    } else {
+        m_rootGraphicsLayer = layer;
+        m_rootLayer = layer ? layer->platformLayer() : 0;
+    }
+
 
     setIsAcceleratedCompositingActive(layer);
 
+    // FIXME: We also need to tell the layer tree about the pinchViewport layers
+    // in a follow-on CL.
     if (m_layerTreeView) {
         if (m_rootLayer)
             m_layerTreeView->setRootLayer(*m_rootLayer);
         else
             m_layerTreeView->clearRootLayer();
     }
 
     suppressInvalidations(false);
 }
 
@@ skipping 14 matching lines @@
         updateLayerTreeViewport();
     } else if (m_client)
         m_client->didInvalidateRect(rect);
 }
 
 WebCore::GraphicsLayerFactory* WebViewImpl::graphicsLayerFactory() const
 {
     return m_graphicsLayerFactory.get();
 }
 
+WebCore::RenderLayerCompositor* WebViewImpl::compositor() const
+{
+    if (!page()
+        || !page()->mainFrame()
+        || !page()->mainFrame()->document()
+        || !page()->mainFrame()->document()->renderView())
+        return 0;
+    return page()->mainFrame()->document()->renderView()->compositor();
+}
+
 void WebViewImpl::registerForAnimations(WebLayer* layer)
 {
     if (m_layerTreeView)
         m_layerTreeView->registerForAnimations(layer);
 }
 
 WebCore::GraphicsLayer* WebViewImpl::rootGraphicsLayer()
 {
     return m_rootGraphicsLayer;
 }
@@ skipping 229 matching lines @@
 }
 
 bool WebViewImpl::shouldDisableDesktopWorkarounds()
 {
     ViewportArguments arguments = mainFrameImpl()->frame()->document()->viewportArguments();
     return arguments.width == ViewportArguments::ValueDeviceWidth || !arguments.userZoom
         || (arguments.minZoom == arguments.maxZoom && arguments.minZoom != ViewportArguments::ValueAuto);
 }
 
 } // namespace WebKit