Gesture event hit test refactoring and reduction

Source/web/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 48 matching lines @@
 #include "core/inspector/InspectorController.h"
 #include "core/loader/DocumentLoader.h"
 #include "core/loader/FrameLoader.h"
 #include "core/loader/UniqueIdentifier.h"
 #include "core/page/Chrome.h"
 #include "core/page/ContextMenuController.h"
 #include "core/page/DragController.h"
 #include "core/page/DragData.h"
 #include "core/page/DragSession.h"
 #include "core/page/EventHandler.h"
+#include "core/page/EventWithHitTestResults.h"
 #include "core/page/FocusController.h"
 #include "core/page/FrameTree.h"
 #include "core/page/InjectedStyleSheets.h"
 #include "core/page/Page.h"
 #include "core/page/PagePopupClient.h"
 #include "core/page/PointerLockController.h"
 #include "core/page/ScopedPageLoadDeferrer.h"
 #include "core/page/TouchDisambiguation.h"
 #include "core/rendering/FastTextAutosizer.h"
 #include "core/rendering/RenderView.h"
@@ skipping 568 matching lines @@
             eventSwallowed = true;
 
         m_client->didHandleGestureEvent(event, eventCancelled);
         return eventSwallowed;
     default:
         break;
     }
 
     PlatformGestureEventBuilder platformEvent(mainFrameImpl()->frameView(), event);
 
+    // FIXME: Remove redundant hit tests by pushing the call to EventHandler::targetGestureEvent
+    // up to this point and pass GestureEventWithHitTestResults around.
+
     // Handle link highlighting outside the main switch to avoid getting lost in the
     // complicated set of cases handled below.
     switch (event.type) {
     case WebInputEvent::GestureShowPress:
         // Queue a highlight animation, then hand off to regular handler.
         if (settingsImpl()->gestureTapHighlightEnabled())
             enableTapHighlightAtPoint(platformEvent);
         break;
     case WebInputEvent::GestureTapCancel:
     case WebInputEvent::GestureTap:
@@ skipping 497 matching lines @@
     if (!node || !node->renderer())
         return false;
 
     ECursor cursor = node->renderer()->style()->cursor();
     return cursor == CURSOR_POINTER
         || (cursor == CURSOR_AUTO && frame->eventHandler().useHandCursor(node, node->isLink()));
 }
 
 Node* WebViewImpl::bestTapNode(const PlatformGestureEvent& tapEvent)
 {
-    if (!m_page || !m_page->mainFrame() || !m_page->mainFrame()->isLocalFrame())
+    TRACE_EVENT0("input", "WebViewImpl::bestTapNode");
+
+    if (!m_page || !m_page->mainFrame())
         return 0;
 
     Node* bestTouchNode = 0;
 
-    IntPoint touchEventLocation(tapEvent.position());
-    m_page->deprecatedLocalMainFrame()->eventHandler().adjustGesturePosition(tapEvent, touchEventLocation);
-
-    IntPoint hitTestPoint = m_page->deprecatedLocalMainFrame()->view()->windowToContents(touchEventLocation);
-    HitTestResult result = m_page->deprecatedLocalMainFrame()->eventHandler().hitTestResultAtPoint(hitTestPoint, HitTestRequest::TouchEvent);
-    bestTouchNode = result.targetNode();
+    // FIXME: Rely on earlier hit test instead of hit testing again.
+    GestureEventWithHitTestResults targetedEvent = m_page->deprecatedLocalMainFrame()->eventHandler().targetGestureEvent(tapEvent, true);
+    bestTouchNode = targetedEvent.hitTestResult().targetNode();
 
     // We might hit something like an image map that has no renderer on it
     // Walk up the tree until we have a node with an attached renderer
     while (bestTouchNode && !bestTouchNode->renderer())
         bestTouchNode = bestTouchNode->parentNode();
 
     // Check if we're in the subtree of a node with a hand cursor
     // this is the heuristic we use to determine if we show a highlight on tap
     while (bestTouchNode && !invokesHandCursor(bestTouchNode, m_page->deprecatedLocalMainFrame()))
         bestTouchNode = bestTouchNode->parentNode();
@@ skipping 614 matching lines @@
 
 bool WebViewImpl::hasVerticalScrollbar()
 {
     return mainFrameImpl()->frameView()->verticalScrollbar();
 }
 
 const WebInputEvent* WebViewImpl::m_currentInputEvent = 0;
 
 // FIXME: autogenerate this kind of code, and use it throughout Blink rather than
 // the one-offs for subsets of these values.
-static const AtomicString* inputTypeToName(WebInputEvent::Type type)
+static String inputTypeToName(WebInputEvent::Type type)
 {
     switch (type) {
     case WebInputEvent::MouseDown:
-        return &EventTypeNames::mousedown;
+        return EventTypeNames::mousedown;
     case WebInputEvent::MouseUp:
-        return &EventTypeNames::mouseup;
+        return EventTypeNames::mouseup;
     case WebInputEvent::MouseMove:
-        return &EventTypeNames::mousemove;
+        return EventTypeNames::mousemove;
     case WebInputEvent::MouseEnter:
-        return &EventTypeNames::mouseenter;
+        return EventTypeNames::mouseenter;
     case WebInputEvent::MouseLeave:
-        return &EventTypeNames::mouseleave;
+        return EventTypeNames::mouseleave;
     case WebInputEvent::ContextMenu:
-        return &EventTypeNames::contextmenu;
+        return EventTypeNames::contextmenu;
     case WebInputEvent::MouseWheel:
-        return &EventTypeNames::mousewheel;
+        return EventTypeNames::mousewheel;
     case WebInputEvent::KeyDown:
-        return &EventTypeNames::keydown;
+        return EventTypeNames::keydown;
     case WebInputEvent::KeyUp:
-        return &EventTypeNames::keyup;
+        return EventTypeNames::keyup;
     case WebInputEvent::GestureScrollBegin:
-        return &EventTypeNames::gesturescrollstart;
+        return EventTypeNames::gesturescrollstart;
     case WebInputEvent::GestureScrollEnd:
-        return &EventTypeNames::gesturescrollend;
+        return EventTypeNames::gesturescrollend;
     case WebInputEvent::GestureScrollUpdate:
-        return &EventTypeNames::gesturescrollupdate;
+        return EventTypeNames::gesturescrollupdate;
+    case WebInputEvent::GestureTapDown:
+        return EventTypeNames::gesturetapdown;
+    case WebInputEvent::GestureShowPress:
+        return EventTypeNames::gestureshowpress;
+    case WebInputEvent::GestureTap:
+        return EventTypeNames::gesturetap;
+    case WebInputEvent::GestureTapUnconfirmed:
+        return EventTypeNames::gesturetapunconfirmed;
     case WebInputEvent::TouchStart:
-        return &EventTypeNames::touchstart;
+        return EventTypeNames::touchstart;
     case WebInputEvent::TouchMove:
-        return &EventTypeNames::touchmove;
+        return EventTypeNames::touchmove;
     case WebInputEvent::TouchEnd:
-        return &EventTypeNames::touchend;
+        return EventTypeNames::touchend;
     case WebInputEvent::TouchCancel:
-        return &EventTypeNames::touchcancel;
+        return EventTypeNames::touchcancel;
     default:
-        return 0;
+        return String("unknown");
     }
 }
 
 bool WebViewImpl::handleInputEvent(const WebInputEvent& inputEvent)
 {
     UserGestureNotifier notifier(m_autofillClient, &m_userGestureObserved);
     // On the first input event since page load, |notifier| instructs the
     // autofill client to unblock values of password input fields of any forms
     // on the page. There is a single input event, GestureTap, which can both
     // be the first event after page load, and cause a form submission. In that
     // case, the form submission happens before the autofill client is told
     // to unblock the password values, and so the password values are not
     // submitted. To avoid that, GestureTap is handled explicitly:
     if (inputEvent.type == WebInputEvent::GestureTap && m_autofillClient) {
         m_userGestureObserved = true;
         m_autofillClient->firstUserGestureObserved();
     }
 
-    const AtomicString* inputEventName = inputTypeToName(inputEvent.type);
-    TRACE_EVENT1("input", "WebViewImpl::handleInputEvent", "type", inputEventName ? inputEventName->ascii() : "unknown");
+    TRACE_EVENT1("input", "WebViewImpl::handleInputEvent", "type", inputTypeToName(inputEvent.type).ascii());
     // If we've started a drag and drop operation, ignore input events until
     // we're done.
     if (m_doingDragAndDrop)
         return true;
 
     if (m_devToolsAgent && m_devToolsAgent->handleInputEvent(m_page.get(), inputEvent))
         return true;
 
     // Report the event to be NOT processed by WebKit, so that the browser can handle it appropriately.
     if (m_ignoreInputEvents)
@@ skipping 2268 matching lines @@
     const PageScaleConstraints& constraints = m_pageScaleConstraintsSet.pageDefinedConstraints();
 
     if (!mainFrameImpl() || !mainFrameImpl()->frameView())
         return false;
 
     return mainFrameImpl()->frameView()->layoutSize().width() == m_size.width
         || (constraints.minimumScale == constraints.maximumScale && constraints.minimumScale != -1);
 }
 
 } // namespace blink