Adding Gesture Recognition to RenderWidgetHostViewWin (web client)

content/browser/renderer_host/render_widget_host_view_win.cc

Index: content/browser/renderer_host/render_widget_host_view_win.cc
diff --git a/content/browser/renderer_host/render_widget_host_view_win.cc b/content/browser/renderer_host/render_widget_host_view_win.cc
index fcfeac8668a7e1e134a9dd0c43aa1c674a2b7eff..2cf791cb644f4d66a803729f493155798ddffb5c 100644
--- a/content/browser/renderer_host/render_widget_host_view_win.cc
+++ b/content/browser/renderer_host/render_widget_host_view_win.cc
@@ -46,6 +46,7 @@
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebCompositionUnderline.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebInputEvent.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/win/WebInputEventFactory.h"
+#include "ui/base/gestures/gesture_recognizer.h"
 #include "ui/base/ime/composition_text.h"
 #include "ui/base/l10n/l10n_util_win.h"
 #include "ui/base/text/text_elider.h"
@@ -57,6 +58,7 @@
 #include "ui/gfx/gdi_util.h"
 #include "ui/gfx/rect.h"
 #include "ui/gfx/screen.h"
+#include "ui/views/events/event.h"

[rjkroege, 2012/05/04 15:42:46]

afaik: content is not allowed to depend on views.

 #include "webkit/glue/webaccessibility.h"
 #include "webkit/glue/webcursor.h"
 #include "webkit/plugins/npapi/plugin_constants_win.h"
@@ -333,6 +335,8 @@ RenderWidgetHostViewWin::RenderWidgetHostViewWin(RenderWidgetHost* widget)
       focus_on_editable_field_(false),
       received_focus_change_after_pointer_down_(false),
       touch_events_enabled_(false),
+      ALLOW_THIS_IN_INITIALIZER_LIST(

[sky, 2012/05/04 16:23:40]

No scoped_ptr since you're creating all the time (I sent rationale in previous
review).

+          gesture_recognizer_(ui::GestureRecognizer::Create(this))),
       ALLOW_THIS_IN_INITIALIZER_LIST(sys_color_change_listener_(this)) {
   render_widget_host_->SetView(this);
   registrar_.Add(this,
@@ -938,6 +942,10 @@ void RenderWidgetHostViewWin::SetBackground(const SkBitmap& background) {
 
 void RenderWidgetHostViewWin::ProcessTouchAck(
     WebKit::WebInputEvent::Type type, bool processed) {
+  scoped_ptr<ui::GestureRecognizer::Gestures> gestures;
+  gestures.reset(gesture_recognizer_->AdvanceTouchQueue(this, processed));
+  ProcessGestures(gestures.get());
+
   if (type == WebKit::WebInputEvent::TouchStart)
     UpdateDesiredTouchMode(processed);
 }
@@ -993,6 +1001,46 @@ void RenderWidgetHostViewWin::UpdateDesiredTouchMode(bool touch_mode) {
   }
 }
 
+ui::GestureEvent* RenderWidgetHostViewWin::CreateGestureEvent(

[rjkroege, 2012/05/04 15:42:46]

my intuition is that this class is not the right place to put this code.

+    ui::EventType type,
+    const gfx::Point& location,
+    int flags,
+    const base::Time& time,
+    float param_first,
+    float param_second,
+    unsigned int touch_id_bitfield) {
+  return new views::GestureEvent(type, location.x(), location.y(), flags, time,
+      param_first, param_second, touch_id_bitfield);
+}
+
+ui::TouchEvent* RenderWidgetHostViewWin::CreateTouchEvent(
+    ui::EventType type,
+    const gfx::Point& location,
+    int touch_id,
+    const base::TimeDelta& time_stamp) {
+  return new views::TouchEvent(
+      type, location.x(), location.y(), 0, touch_id, 0, 0, 0, 0);
+}
+
+bool RenderWidgetHostViewWin::DispatchLongPressGestureEvent(
+    ui::GestureEvent* event) {
+  return ForwardGestureEventToRenderer( WebKit::WebInputEvent::GestureLongPress,
+      reinterpret_cast< const views::GestureEvent *>(event));
+}
+
+bool RenderWidgetHostViewWin::DispatchCancelTouchEvent(
+    ui::TouchEvent* event) {
+  if (!render_widget_host_)
+    return false;
+
+  WebKit::WebTouchEvent generatedEvent;
+  generatedEvent.changedTouchesLength = 1;
+  generatedEvent.changedTouches[0].id = event->GetTouchId();
+  generatedEvent.type = WebKit::WebInputEvent::TouchCancel;
+  render_widget_host_->ForwardTouchEvent(generatedEvent);
+  return true;
+}
+
 void RenderWidgetHostViewWin::SetHasHorizontalScrollbar(
     bool has_horizontal_scrollbar) {
 }
@@ -1897,18 +1945,117 @@ LRESULT RenderWidgetHostViewWin::OnTouchEvent(UINT message, WPARAM wparam,
                                    points, sizeof(TOUCHINPUT))) {
     return 0;
   }
-
   for (size_t start = 0; start < total;) {
     start += touch_state_.UpdateTouchPoints(points + start, total - start);
     if (touch_state_.is_changed())
       render_widget_host_->ForwardTouchEvent(touch_state_.touch_event());

[rjkroege, 2012/05/04 15:42:46]

are the touch-ids normalized here?

   }
 
+  // Send a copy of the touch events on to the gesture recognizer.
+  for (size_t index = 0; index < total; ++index) {
+    // Create a views::TouchEvent
+    bool hasAreaInfo =
+        (points[index].dwMask & TOUCHINPUTMASKF_CONTACTAREA) != 0;
+
+    DWORD flags = points[index].dwFlags;
+    ui::EventType eventType = ui::ET_TOUCH_STATIONARY;
+
+    if ((flags & TOUCHEVENTF_UP) != 0)
+      eventType = ui::ET_TOUCH_RELEASED;
+    else if ((flags & TOUCHEVENTF_MOVE) != 0) {
+      eventType = ui::ET_TOUCH_MOVED;
+      // Ignore this touch if there is a backlog.

[rjkroege, 2012/05/04 15:42:46]

why? you drop the moves on the floor?

wouldn't the right model be to coalesce the moves like mousemoves before sending
the touches to webkit but sending every event sent to webkit to the GR.

The GR ought to be very fast compared to a trip to WebKit and so should have no
trouble keeping up?

+      if (!gesture_recognizer_->IsQueueEmpty(this))
+        continue;
+    }
+    else if ((flags & TOUCHEVENTF_DOWN) != 0)
+      eventType = ui::ET_TOUCH_PRESSED;
+
+    views::TouchEvent touchEvent( eventType,
+        TOUCH_COORD_TO_PIXEL( points[index].x),
+        TOUCH_COORD_TO_PIXEL( points[index].y),
+        0, // flags are not used.
+        points[index].dwID,
+        hasAreaInfo ? points[index].cxContact : 0.0,
+        hasAreaInfo ? points[index].cyContact : 0.0,
+        0.0, // angle is unknown?
+        0.0); // force is 0?
+    GestureConsumer* consumer = this;
+    gesture_recognizer_->QueueTouchEventForGesture(
+      consumer, touchEvent);
+  }
+
   CloseTouchInputHandle((HTOUCHINPUT)lparam);
 
   return 0;
 }
 
+void RenderWidgetHostViewWin::ProcessGestures(
+    ui::GestureRecognizer::Gestures* gestures) {
+  if ((gestures == 0) || gestures->empty())
+    return;
+
+  for (ui::GestureRecognizer::Gestures::iterator g_it = gestures->begin();

[rjkroege, 2012/05/04 15:42:46]

we have code that knows how to make Web events out of aura events. Maybe it
should make Web events out of ui events instead? then this code wouldn't need to
be here too?

+      g_it != gestures->end();
+      ++g_it) {
+    views::GestureEvent *gesture =
+        reinterpret_cast<views::GestureEvent *>( *g_it);
+    switch (gesture->type()) {
+    case ui::ET_GESTURE_SCROLL_BEGIN:
+      ForwardGestureEventToRenderer(WebKit::WebInputEvent::GestureScrollBegin,
+          gesture);
+      break;
+    case ui::ET_GESTURE_SCROLL_END:
+      ForwardGestureEventToRenderer(WebKit::WebInputEvent::GestureScrollEnd,
+          gesture);
+      break;
+    case ui::ET_GESTURE_SCROLL_UPDATE:
+      ForwardGestureEventToRenderer(WebKit::WebInputEvent::GestureScrollUpdate,
+          gesture);
+      break;
+    case ui::ET_GESTURE_PINCH_BEGIN:
+      ForwardGestureEventToRenderer(WebKit::WebInputEvent::GesturePinchBegin,
+          gesture);
+      break;
+    case ui::ET_GESTURE_PINCH_END:
+      ForwardGestureEventToRenderer(WebKit::WebInputEvent::GesturePinchEnd,
+          gesture);
+      break;
+    case ui::ET_GESTURE_PINCH_UPDATE:
+      ForwardGestureEventToRenderer(WebKit::WebInputEvent::GesturePinchUpdate,
+          gesture);
+      break;
+    case ui::ET_GESTURE_LONG_PRESS:
+      ForwardGestureEventToRenderer(WebKit::WebInputEvent::GestureLongPress,
+          gesture);
+      break;
+    case ui::ET_GESTURE_THREE_FINGER_SWIPE:
+      // TODO: Add this code when three finger swipes are added.
+      //ForwardGestureEventToRenderer(
+      //    WebKit::WebInputEvent::GestureThreeFingerSwipe, gesture);
+      break;
+    case ui::ET_GESTURE_TAP:
+      if (!ForwardGestureEventToRenderer(WebKit::WebInputEvent::GestureTap,
+          gesture))
+        ForwardMouseEventToRenderer(WM_LBUTTONUP, 0,
+            MAKELONG(gesture->x(),gesture->y()));
+      break;
+    case ui::ET_GESTURE_TAP_DOWN:

[rjkroege, 2012/05/04 15:42:46]

Something looks wrong here. Taps from the GR are handled in WebKit. I would
expect this to do the wrong thing.

+      if (!ForwardGestureEventToRenderer(WebKit::WebInputEvent::GestureTapDown,
+            gesture))
+        ForwardMouseEventToRenderer(WM_LBUTTONDOWN, 0,
+            MAKELONG(gesture->x(),gesture->y()));
+      break;
+    case ui::ET_GESTURE_DOUBLE_TAP:
+      if (!ForwardGestureEventToRenderer(
+            WebKit::WebInputEvent::GestureDoubleTap, gesture))
+        ForwardMouseEventToRenderer(WM_LBUTTONDBLCLK, 0,

[rjkroege, 2012/05/04 15:42:46]

Same comment

+            MAKELONG(gesture->x(),gesture->y()));
+      break;
+    }
+  }
+}
+
 LRESULT RenderWidgetHostViewWin::OnMouseActivate(UINT message,
                                                  WPARAM wparam,
                                                  LPARAM lparam,
@@ -2452,6 +2599,24 @@ void RenderWidgetHostViewWin::ResetTooltip() {
   tooltip_hwnd_ = NULL;
 }
 
+bool RenderWidgetHostViewWin::ForwardGestureEventToRenderer(
+    WebKit::WebInputEvent::Type eventType,
+    const views::GestureEvent* gesture) {
+  if (!render_widget_host_)
+    return false;
+
+  WebKit::WebGestureEvent generatedEvent;
+  generatedEvent.x = gesture->x();
+  generatedEvent.y = gesture->y();
+  generatedEvent.deltaX = gesture->delta_x();
+  generatedEvent.deltaY = gesture->delta_y();
+  generatedEvent.timeStampSeconds =
+      gesture->time_stamp().UnixEpoch().ToDoubleT();
+  generatedEvent.type = eventType;
+  render_widget_host_->ForwardGestureEvent(generatedEvent);
+  return true;
+}
+
 void RenderWidgetHostViewWin::ForwardMouseEventToRenderer(UINT message,
                                                           WPARAM wparam,
                                                           LPARAM lparam) {