ppapi/cpp/touch_point.h

   1 // Copyright (c) 2012 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 PPAPI_CPP_TOUCH_POINT_H_
   6 #define PPAPI_CPP_TOUCH_POINT_H_
   7
   8 #include "ppapi/c/ppb_input_event.h"
   9 #include "ppapi/cpp/input_event.h"
  10 #include "ppapi/cpp/point.h"
  11
  12 namespace pp {
  13
  14 /// Wrapper class for PP_TouchPoint.
  15 class TouchPoint {
  16  public:
  17   TouchPoint() : touch_point_(PP_MakeTouchPoint()) {}
  18
  19   TouchPoint(const PP_TouchPoint& point) : touch_point_(point) {}
  20
  21   /// @return The identifier for this TouchPoint. This corresponds to the order
  22   /// in which the points were pressed. For example, the first point to be
  23   /// pressed has an id of 0, the second has an id of 1, and so on. An id can be
  24   /// reused when a touch point is released.  For example, if two fingers are
  25   /// down, with id 0 and 1, and finger 0 releases, the next finger to be
  26   /// pressed can be assigned to id 0.
  27   uint32_t id() const { return touch_point_.id; }
  28
  29   /// @return The x-y coordinates of this TouchPoint, in DOM coordinate space.
  30   FloatPoint position() const {
  31     return pp::FloatPoint(touch_point_.position);
  32   }
  33
  34   /// @return The elliptical radii, in screen pixels, in the x and y direction
  35   /// of this TouchPoint.
  36   FloatPoint radii() const { return pp::FloatPoint(touch_point_.radius); }
  37
  38   /// @return The angle of rotation of the elliptical model of this TouchPoint
  39   /// from the y-axis.
  40   float rotation_angle() const { return touch_point_.rotation_angle; }
  41
  42   /// @return The pressure applied to this TouchPoint.  This is typically a
  43   /// value between 0 and 1, with 0 indicating no pressure and 1 indicating
  44   /// some maximum pressure, but scaling differs depending on the hardware and
  45   /// the value is not guaranteed to stay within that range.
  46   float pressure() const { return touch_point_.pressure; }
  47
  48  private:
  49   PP_TouchPoint touch_point_;
  50 };
  51
  52 }  // namespace pp
  53
  54 #endif  /* PPAPI_CPP_TOUCH_POINT_H_ */