Revert 139473 - Revert 139398 - gesture recognizer: Allow multi-finger pinch/scroll gestures.

Instead of having specific X-finger gestures (e.g. three-finger swipe,
two-finger pinch), add support for gestures with a variable number of fingers
(e.g. two-finger pinch and three-finger pinch etc.)

BUG=121140
TEST=none

Review URL: https://chromiumcodereview.appspot.com/10137010

TBR=sadrul@chromium.org
Review URL: https://chromiumcodereview.appspot.com/10449065

TBR=kinuko@chromium.org
Review URL: https://chromiumcodereview.appspot.com/10454068

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@139486 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 29 insertions, 18 deletions

diff --git a/ui/base/gestures/gesture_sequence.h b/ui/base/gestures/gesture_sequence.h
index e8d7aab..b8a9a02 100644
--- a/ui/base/gestures/gesture_sequence.h
+++ b/ui/base/gestures/gesture_sequence.h
@@ -10,6 +10,7 @@
 #include "ui/base/events.h"
 #include "ui/base/gestures/gesture_point.h"
 #include "ui/base/gestures/gesture_recognizer.h"
+#include "ui/gfx/rect.h"
 
 namespace ui {
 class TouchEvent;
@@ -21,7 +22,6 @@ enum GestureState {
   GS_PENDING_SYNTHETIC_CLICK,
   GS_SCROLL,
   GS_PINCH,
-  GS_THREE_FINGER_SWIPE
 };
 
 enum ScrollType {
@@ -59,6 +59,12 @@ class UI_EXPORT GestureSequence {
  private:
   void Reset();
 
+  // Recreates the axis-aligned bounding box that contains all the touch-points
+  // at their most recent position.
+  void RecreateBoundingBox();
+
+  void ResetVelocities();
+
   GesturePoint& GesturePointForEvent(const TouchEvent& event);
 
   // Do a linear scan through points_ to find the GesturePoint
@@ -69,6 +75,7 @@ class UI_EXPORT GestureSequence {
 
   // Tap gestures.
   void AppendTapDownGestureEvent(const GesturePoint& point, Gestures* gestures);
+  void AppendTapUpGestureEvent(const GesturePoint& point, Gestures* gestures);
   void AppendClickGestureEvent(const GesturePoint& point, Gestures* gestures);
   void AppendDoubleClickGestureEvent(const GesturePoint& point,
                                      Gestures* gestures);
@@ -95,17 +102,13 @@ class UI_EXPORT GestureSequence {
                              const GesturePoint& p2,
                              float scale,
                              Gestures* gestures);
-  void AppendPinchGestureUpdate(const GesturePoint& p1,
-                                const GesturePoint& p2,
+  void AppendPinchGestureUpdate(const GesturePoint& point,
                                 float scale,
                                 Gestures* gestures);
-
-  void AppendThreeFingerSwipeGestureEvent(const GesturePoint& p1,
-                                          const GesturePoint& p2,
-                                          const GesturePoint& p3,
-                                          float x_velocity,
-                                          float y_velocity,
-                                          Gestures* gestures);
+  void AppendSwipeGesture(const GesturePoint& point,
+                          int swipe_x,
+                          int swipe_y,
+                          Gestures* gestures);
 
   void set_state(const GestureState state ) { state_ = state; }
 
@@ -116,11 +119,11 @@ class UI_EXPORT GestureSequence {
              const GesturePoint& point,
              Gestures* gestures);
   bool ScrollStart(const TouchEvent& event,
-                             GesturePoint& point,
-                             Gestures* gestures);
+                   GesturePoint& point,
+                   Gestures* gestures);
   void BreakRailScroll(const TouchEvent& event,
-                               GesturePoint& point,
-                               Gestures* gestures);
+                       GesturePoint& point,
+                       Gestures* gestures);
   bool ScrollUpdate(const TouchEvent& event,
                     const GesturePoint& point,
                     Gestures* gestures);
@@ -142,9 +145,9 @@ class UI_EXPORT GestureSequence {
   bool PinchEnd(const TouchEvent& event,
                 const GesturePoint& point,
                 Gestures* gestures);
-  bool ThreeFingerSwipeUpdate(const TouchEvent& event,
-                              const GesturePoint& point,
-                              Gestures* gestures);
+  bool MaybeSwipe(const TouchEvent& event,
+                  const GesturePoint& point,
+                  Gestures* gestures);
 
   // Current state of gesture recognizer.
   GestureState state_;
@@ -152,6 +155,15 @@ class UI_EXPORT GestureSequence {
   // ui::EventFlags.
   int flags_;
 
+  // We maintain the smallest axis-aligned rectangle that contains all the
+  // current touch-points. The 'distance' represents the diagonal distance.
+  // This box is updated after every touch-event.
+  gfx::Rect bounding_box_;
+  gfx::Point bounding_box_last_center_;
+
+  // For pinch, the 'distance' represents the diagonal distance of
+  // |bounding_box_|.
+
   // The distance between the two points at PINCH_START.
   float pinch_distance_start_;
 
@@ -159,7 +171,6 @@ class UI_EXPORT GestureSequence {
   float pinch_distance_current_;
 
   ScrollType scroll_type_;
-  bool three_finger_swipe_has_fired_;
   scoped_ptr<base::OneShotTimer<GestureSequence> > long_press_timer_;
 
   GesturePoint points_[kMaxGesturePoints];