Add movement information to PPB_MouseInputEvent.

ppapi/cpp/input_event.h

 // Copyright (c) 2011 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.
 
 #ifndef PPAPI_CPP_INPUT_EVENT_H_
 #define PPAPI_CPP_INPUT_EVENT_H_
 
 #include <string>
 
 #include "ppapi/c/ppb_input_event.h"
@@ skipping 105 matching lines @@
   /// @param[in] mouse_button The button that changed for mouse down or up
   /// events. This value will be <code>PP_EVENT_MOUSEBUTTON_NONE</code> for
   /// mouse move, enter, and leave events.
   ///
   /// @param[in] mouse_position A <code>Point</code> containing the x and y
   /// position of the mouse when the eent occurred.
   ///
   /// @param[in] click_count
   /// TODO(brettw) figure out exactly what this means.
   ///
+  /// @param[in] mouse_movement The change in position of the mouse.
   MouseInputEvent(Instance* instance,
                   PP_InputEvent_Type type,
                   PP_TimeTicks time_stamp,
                   uint32_t modifiers,
                   PP_InputEvent_MouseButton mouse_button,
                   const Point& mouse_position,
-                  int32_t click_count);
+                  int32_t click_count,
+                  const Point& mouse_movement);
 
   /// GetButton() returns the mouse position for a mouse input event.
   ///
   /// @return The mouse button associated with mouse down and up events. This
   /// value will be PP_EVENT_MOUSEBUTTON_NONE for mouse move, enter, and leave
   /// events, and for all non-mouse events.
   PP_InputEvent_MouseButton GetButton() const;
 
-  /// GetPostion() returns the pixel location of a mouse input event. This
-  /// value is in floating-point units to support high-resolution input events.
+  /// GetPosition() returns the pixel location of a mouse input event. When
+  /// the mouse is locked, it returns the last known mouse position just as
+  /// mouse lock was entered.
   ///
   /// @return The point associated with the mouse event, relative to the upper-
   /// left of the instance receiving the event. These values can be negative for
   /// mouse drags. The return value will be (0, 0) for non-mouse events.
   Point GetPosition() const;
 
   // TODO(brettw) figure out exactly what this means.
   int32_t GetClickCount() const;
+
+  /// Returns the change in position of the mouse. When the mouse is locked,
+  /// although the mouse position doesn't actually change, this function
+  /// still provides movement information, which indicates what the change in
+  /// position would be had the mouse not been locked.
+  ///
+  /// @return The change in position of the mouse, relative to the previous
+  /// position.
+  Point GetMovement() const;
 };
 
 class WheelInputEvent : public InputEvent {
  public:
   /// Constructs an is_null() wheel input event object.
   WheelInputEvent();
 
   /// This constructor constructs a wheel input event object from the
   /// provided generic input event. If the given event is itself
   /// is_null() or is not a wheel input event, the wheel object will be
@@ skipping 121 matching lines @@
   ///
   /// @return A string var representing a single typed character for character
   /// input events. For non-character input events the return value will be an
   /// undefined var.
   Var GetCharacterText() const;
 };
 
 }  // namespace pp
 
 #endif  // PPAPI_CPP_INPUT_EVENT_H_