Move touch hit testing to PointerEventManager

third_party/WebKit/Source/core/input/PointerEventManager.cpp

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/input/PointerEventManager.h"
 
 #include "core/dom/ElementTraversal.h"
 #include "core/dom/shadow/FlatTreeTraversal.h"
 #include "core/events/MouseEvent.h"
 #include "core/frame/FrameView.h"
 #include "core/html/HTMLCanvasElement.h"
 #include "core/input/EventHandler.h"
+#include "core/input/TouchActionUtil.h"
+#include "core/page/ChromeClient.h"
+#include "core/page/Page.h"
 #include "platform/PlatformTouchEvent.h"
 
 namespace blink {
 
 namespace {
 
 size_t toPointerTypeIndex(WebPointerProperties::PointerType t) { return static_cast<size_t>(t); }
 
 const AtomicString& pointerEventNameForTouchPointState(PlatformTouchPoint::TouchState state)
 {
@@ skipping 367 matching lines @@
     for (const auto &touchPoint : event.touchPoints()) {
         if (touchPoint.state() != PlatformTouchPoint::TouchPressed) {
             newTouchSequence = false;
             break;
         }
     }
     if (newTouchSequence)
         unblockTouchPointers();
     HeapVector<TouchEventManager::TouchInfo> touchInfos;
 
-    // TODO(crbug.com/606822): This will be moved after pointer events so
-    // pointer event operations will get the first shot to fill up this array.
-    if (!m_touchEventManager.generateTouchInfosAfterHittest(event, touchInfos))
-        return WebInputEventResult::NotHandled;
-
     dispatchTouchPointerEvents(event, touchInfos);
 
     return m_touchEventManager.handleTouchEvent(event, touchInfos);
 }
 
 void PointerEventManager::dispatchTouchPointerEvents(
     const PlatformTouchEvent& event,
     HeapVector<TouchEventManager::TouchInfo>& touchInfos)
 {
-    if (!RuntimeEnabledFeatures::pointerEventEnabled())
-        return;
+    // Iterate through the touch points, sending PointerEvents to the targets as required.
+    for (const auto& touchPoint : event.touchPoints()) {
+        TouchEventManager::TouchInfo touchInfo;
+        touchInfo.point = touchPoint;
 
-    if (m_inCanceledStateForPointerTypeTouch)
-        return;
+        int pointerId = m_pointerEventFactory.getPointerEventId(
+            touchPoint.pointerProperties());
+        // Do the hit test either when the touch first starts or when the touch
+        // is not captured. |m_pendingPointerCaptureTarget| indicates the target
+        // that will be capturing this event. |m_pointerCaptureTarget| may not
+        // have this target yet since the processing of that will be done right
+        // before firing the event.
+        if (touchInfo.point.state() == PlatformTouchPoint::TouchPressed
+            || !m_pendingPointerCaptureTarget.contains(pointerId)) {
+            HitTestRequest::HitTestRequestType hitType = HitTestRequest::TouchEvent | HitTestRequest::ReadOnly | HitTestRequest::Active;
+            LayoutPoint pagePoint = roundedLayoutPoint(m_frame->view()->rootFrameToContents(touchInfo.point.pos()));
+            HitTestResult hitTestTesult = m_frame->eventHandler().hitTestResultAtPoint(pagePoint, hitType);
+            Node* node = hitTestTesult.innerNode();
+            if (node) {
+                touchInfo.targetFrame = node->document().frame();
+                if (isHTMLCanvasElement(node)) {
+                    std::pair<Element*, String> regionInfo = toHTMLCanvasElement(node)->getControlAndIdIfHitRegionExists(hitTestTesult.pointInInnerNodeFrame());
+                    if (regionInfo.first)
+                        node = regionInfo.first;
+                    touchInfo.region = regionInfo.second;
+                }
+                // Touch events should not go to text nodes.

[Rick Byers, 2016/05/17 14:20:01]

update comment, probably even file a bug to track updating behavior.  Do mouse
events go to text nodes?  Do pointer events on Edge?

[Navid Zolghadr, 2016/05/17 16:40:44]

I don't know to be honest with you. This is the behavior from the previous code
and I just didn't change it. I added a TODO to double check it later.

+                if (node->isTextNode())
+                    node = FlatTreeTraversal::parent(*node);
+                touchInfo.touchNode = node;
 
-    // Iterate through the touch points, sending PointerEvents to the targets as required.
-    for (auto& touchInfo: touchInfos) {
-        const PlatformTouchPoint &touchPoint = touchInfo.point;
+            }
+        } else {
+            // Set the target of pointer event to the captured node as this
+            // pointer is captured otherwise it would have gone to the if block
+            // and perform a hit-test.
+            touchInfo.touchNode = m_pendingPointerCaptureTarget
+                .get(pointerId)->toNode();
+            touchInfo.targetFrame = touchInfo.touchNode->document().frame();
+        }
+
         WebInputEventResult result = WebInputEventResult::NotHandled;
-        // Do not send pointer events for stationary touches.
-        if (touchPoint.state() != PlatformTouchPoint::TouchStationary) {
+
+        // Do not send pointer events for stationary touches or null targetFrame
+        if (touchInfo.touchNode
+            && touchPoint.state() != PlatformTouchPoint::TouchStationary
+            && !m_inCanceledStateForPointerTypeTouch) {
+            FloatPoint pagePoint = touchInfo.targetFrame->view()
+                ->rootFrameToContents(touchInfo.point.pos());
             float scaleFactor = 1.0f / touchInfo.targetFrame->pageZoomFactor();
             FloatPoint scrollPosition = touchInfo.targetFrame->view()->scrollPosition();
-            FloatPoint framePoint = touchInfo.contentPoint;
+            FloatPoint framePoint = pagePoint.scaledBy(scaleFactor);
             framePoint.moveBy(scrollPosition.scaledBy(-scaleFactor));
             PointerEvent* pointerEvent = m_pointerEventFactory.create(
                 pointerEventNameForTouchPointState(touchPoint.state()),
                 touchPoint, event.getModifiers(),
-                touchInfo.adjustedRadius,
+                touchPoint.radius().scaledBy(scaleFactor),
                 framePoint);
 
             // Consume the touch point if its pointer event is anything but NotHandled
             // (e.g. preventDefault is called in the listener for the pointer event).
             result = sendTouchPointerEvent(touchInfo.touchNode, pointerEvent);
-            touchInfo.consumed = result != WebInputEventResult::NotHandled;
+        }
+        if (result == WebInputEventResult::NotHandled) {
+            touchInfos.append(touchInfo);

[Rick Byers, 2016/05/17 14:20:01]

So the touchinfos are now just the data needed for generating touch events? 
Update the function description to make that clear (it still refers to the
consumed bit).

Is this preserving the existing behavior though?  Eg. what happens if code
consumes the pointerdown but not the pointermove/pointerup?  For mouse, we don't
generate any compat mouse events in that case.  For touch we'd send a
touchmove/touchend but not a touchstart?  That's probably wrong.  But if you're
not making this any worse in this CL, feel free to just file a bug and add a
TODO here referencing it.

[mustaq, 2016/05/17 14:40:14]

We already have a p1 bug for this: crbug.com/607588. We will follow the Edge
behavior here (see #1 in that bug), which makes the most sense. We have a nearly
complete patch for GestureTap, using uniqueTouchIds.

So in summary, we expect this to change soon, and we don't need to file a bug.

[Navid Zolghadr, 2016/05/17 16:40:44]

Yup. I haven't changed the behavior here and just kept what it was. Mustaq is
looking into changing the behavior to follow Edge. I added the TODO as you
suggested.

         }
     }
 }
 
 WebInputEventResult PointerEventManager::sendTouchPointerEvent(
     EventTarget* target, PointerEvent* pointerEvent)
 {
     if (m_inCanceledStateForPointerTypeTouch)
         return WebInputEventResult::NotHandled;
 
@@ skipping 282 matching lines @@
 {
     visitor->trace(m_frame);
     visitor->trace(m_nodeUnderPointer);
     visitor->trace(m_pointerCaptureTarget);
     visitor->trace(m_pendingPointerCaptureTarget);
     visitor->trace(m_touchEventManager);
 }
 
 
 } // namespace blink