Implemented smooth scrolling using xinput2 in X11.

ui/events/x/events_x.cc

 // Copyright (c) 2012 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 "ui/events/event_constants.h"
 
 #include <cmath>
 #include <string.h>
 #include <X11/extensions/XInput.h>
 #include <X11/extensions/XInput2.h>
@@ skipping 426 matching lines @@
         }
         case XI_Motion: {
           bool is_cancel;
           DeviceDataManagerX11* devices = DeviceDataManagerX11::GetInstance();
           if (GetFlingData(native_event, NULL, NULL, NULL, NULL, &is_cancel))
             return is_cancel ? ET_SCROLL_FLING_CANCEL : ET_SCROLL_FLING_START;
           if (devices->IsScrollEvent(native_event)) {
             return devices->IsTouchpadXInputEvent(native_event) ? ET_SCROLL
                                                                 : ET_MOUSEWHEEL;
           }
+          if (devices->IsScrollClassEvent(native_event)) {
+            return ET_MOUSEWHEEL;
+          }

[sadrul, 2014/12/22 17:11:12]

no {}

           if (devices->IsCMTMetricsEvent(native_event))
             return ET_UMA_DATA;
           if (GetButtonMaskForX2Event(xievent))
             return ET_MOUSE_DRAGGED;
           return ET_MOUSE_MOVED;
         }
         case XI_KeyPress:
           return ET_KEY_PRESSED;
         case XI_KeyRelease:
           return ET_KEY_RELEASED;
@@ skipping 252 matching lines @@
 }
 
 gfx::Vector2d GetMouseWheelOffset(const base::NativeEvent& native_event) {
   float x_offset, y_offset;
   if (GetScrollOffsets(
       native_event, &x_offset, &y_offset, NULL, NULL, NULL)) {
     return gfx::Vector2d(static_cast<int>(x_offset),
                          static_cast<int>(y_offset));
   }
 
+  double x_scroll_offset, y_scroll_offset;
+  if (DeviceDataManagerX11::GetInstance()->IsScrollClassEvent(native_event)) {
+    DeviceDataManagerX11::GetInstance()->GetScrollClassOffsets(
+        native_event,
+        &x_scroll_offset, &y_scroll_offset);
+    return gfx::Vector2d(
+        static_cast<int>(x_scroll_offset * kWheelScrollAmount),
+        static_cast<int>(y_scroll_offset * kWheelScrollAmount));
+  }
+

[sadrul, 2014/12/22 17:11:12]

Can this block move into GetScrollOffsets() instead?

   int button = native_event->type == GenericEvent ?
       EventButtonFromNative(native_event) : native_event->xbutton.button;
 
+  bool verticalScrollClass =
+    DeviceDataManagerX11::GetInstance()
+    ->IsScrollClassVerticalDevice(native_event);
+  bool horizontalScrollClass =

[sadrul, 2014/12/22 17:11:12]

Should be vertical_scroll_class etc.

+    DeviceDataManagerX11::GetInstance()
+    ->IsScrollClassHorizontalDevice(native_event);
+
   switch (button) {
     case 4:
-      return gfx::Vector2d(0, kWheelScrollAmount);
+      return gfx::Vector2d(0, verticalScrollClass ? 0 : kWheelScrollAmount);
     case 5:
-      return gfx::Vector2d(0, -kWheelScrollAmount);
+      return gfx::Vector2d(0, verticalScrollClass ? 0 : -kWheelScrollAmount);
     case 6:
-      return gfx::Vector2d(kWheelScrollAmount, 0);
+      return gfx::Vector2d(horizontalScrollClass ? 0 : kWheelScrollAmount, 0);
     case 7:
-      return gfx::Vector2d(-kWheelScrollAmount, 0);
+      return gfx::Vector2d(horizontalScrollClass ? 0 : -kWheelScrollAmount, 0);
     default:
       return gfx::Vector2d();
   }
 }
 
 base::NativeEvent CopyNativeEvent(const base::NativeEvent& event) {
   if (!event || event->type == GenericEvent)
     return NULL;
   XEvent* copy = new XEvent;
   *copy = *event;
@@ skipping 179 matching lines @@
       xievent->detail =
           UpdateX11EventButton(event->changed_button_flags(), xievent->detail);
       break;
     }
     default:
       break;
   }
 }
 
 }  // namespace ui