ui/events/gesture_detection/motion_event.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef UI_EVENTS_GESTURE_DETECTION_MOTION_EVENT_H_
   6 #define UI_EVENTS_GESTURE_DETECTION_MOTION_EVENT_H_
   7
   8 #include "base/memory/scoped_ptr.h"
   9 #include "base/time/time.h"
  10 #include "ui/events/gesture_detection/gesture_detection_export.h"
  11
  12 namespace ui {
  13
  14 // Abstract class for a generic motion-related event, patterned after that
  15 // subset of Android's MotionEvent API used in gesture detection.
  16 class GESTURE_DETECTION_EXPORT MotionEvent {
  17  public:
  18   enum Action {
  19     ACTION_DOWN,
  20     ACTION_UP,
  21     ACTION_MOVE,
  22     ACTION_CANCEL,
  23     ACTION_POINTER_DOWN,
  24     ACTION_POINTER_UP,
  25   };
  26
  27   enum ToolType {
  28     TOOL_TYPE_UNKNOWN,
  29     TOOL_TYPE_FINGER,
  30     TOOL_TYPE_STYLUS,
  31     TOOL_TYPE_MOUSE,
  32     TOOL_TYPE_ERASER
  33   };
  34
  35   enum ButtonType {
  36     BUTTON_PRIMARY = 1 << 0,
  37     BUTTON_SECONDARY = 1 << 1,
  38     BUTTON_TERTIARY = 1 << 2,
  39     BUTTON_BACK = 1 << 3,
  40     BUTTON_FORWARD = 1 << 4,
  41   };
  42
  43   // The implementer promises that |GetPointerId()| will never exceed
  44   // MAX_POINTER_ID.
  45   enum { MAX_POINTER_ID = 31, MAX_TOUCH_POINT_COUNT = 12 };
  46
  47   virtual ~MotionEvent() {}
  48
  49   virtual int GetId() const = 0;
  50   virtual Action GetAction() const = 0;
  51   // Only valid if |GetAction()| returns ACTION_POINTER_UP or
  52   // ACTION_POINTER_DOWN.
  53   virtual int GetActionIndex() const = 0;
  54   virtual size_t GetPointerCount() const = 0;
  55   virtual int GetPointerId(size_t pointer_index) const = 0;
  56   virtual float GetX(size_t pointer_index) const = 0;
  57   virtual float GetY(size_t pointer_index) const = 0;
  58   virtual float GetRawX(size_t pointer_index) const = 0;
  59   virtual float GetRawY(size_t pointer_index) const = 0;
  60   virtual float GetTouchMajor(size_t pointer_index) const = 0;
  61   virtual float GetPressure(size_t pointer_index) const = 0;
  62   virtual ToolType GetToolType(size_t pointer_index) const = 0;
  63   virtual int GetButtonState() const = 0;
  64   virtual base::TimeTicks GetEventTime() const = 0;
  65
  66   // Optional historical data, default implementation provides an empty history.
  67   virtual size_t GetHistorySize() const;
  68   virtual base::TimeTicks GetHistoricalEventTime(size_t historical_index) const;
  69   virtual float GetHistoricalTouchMajor(size_t pointer_index,
  70                                         size_t historical_index) const;
  71   virtual float GetHistoricalX(size_t pointer_index,
  72                                size_t historical_index) const;
  73   virtual float GetHistoricalY(size_t pointer_index,
  74                                size_t historical_index) const;
  75
  76   virtual scoped_ptr<MotionEvent> Clone() const = 0;
  77   virtual scoped_ptr<MotionEvent> Cancel() const = 0;
  78
  79   // Utility accessor methods for convenience.
  80   float GetX() const { return GetX(0); }
  81   float GetY() const { return GetY(0); }
  82   float GetRawX() const { return GetRawX(0); }
  83   float GetRawY() const { return GetRawY(0); }
  84   float GetRawOffsetX() const { return GetRawX() - GetX(); }
  85   float GetRawOffsetY() const { return GetRawY() - GetY(); }
  86   float GetTouchMajor() const { return GetTouchMajor(0); }
  87   float GetPressure() const { return GetPressure(0); }
  88   ToolType GetToolType() const { return GetToolType(0); }
  89
  90   // O(N) search of pointers (use sparingly!). Returns -1 if |id| nonexistent.
  91   int FindPointerIndexOfId(int id) const;
  92 };
  93
  94 GESTURE_DETECTION_EXPORT bool operator==(const MotionEvent& lhs,
  95                                          const MotionEvent& rhs);
  96 GESTURE_DETECTION_EXPORT bool operator!=(const MotionEvent& lhs,
  97                                          const MotionEvent& rhs);
  98
  99 }  // namespace ui
 100
 101 #endif  // UI_EVENTS_GESTURE_DETECTION_MOTION_EVENT_H_