chromeos/accelerometer/accelerometer_types.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 CHROMEOS_ACCELEROMETER_ACCELEROMETER_TYPES_H_
   6 #define CHROMEOS_ACCELEROMETER_ACCELEROMETER_TYPES_H_
   7
   8 #include "base/macros.h"
   9 #include "chromeos/chromeos_export.h"
  10
  11 namespace chromeos {
  12
  13 enum AccelerometerSource {
  14   // Accelerometer is located in the device's screen. In the screen's natural
  15   // orientation, positive X points to the right, consistent with the pixel
  16   // position. Positive Y points up the screen. Positive Z is perpendicular to
  17   // the screen, pointing outwards towards the user. The orientation is
  18   // described at:
  19   // http://www.html5rocks.com/en/tutorials/device/orientation/.
  20   ACCELEROMETER_SOURCE_SCREEN = 0,
  21
  22   // Accelerometer is located in a keyboard attached to the device's screen.
  23   // If the device is open 180 degrees the orientation is consistent with the
  24   // screen. I.e. Positive X points to the right, positive Y points up on the
  25   // keyboard and positive Z is perpendicular to the keyboard pointing out
  26   // towards the user.
  27   ACCELEROMETER_SOURCE_ATTACHED_KEYBOARD,
  28
  29   ACCELEROMETER_SOURCE_COUNT
  30 };
  31
  32 struct CHROMEOS_EXPORT AccelerometerReading {
  33   AccelerometerReading();
  34   ~AccelerometerReading();
  35
  36   // If true, this accelerometer is being updated.
  37   bool present;
  38
  39   // The readings from this accelerometer measured in m/s^2.
  40   float x;
  41   float y;
  42   float z;
  43 };
  44
  45 // An accelerometer update contains the last known value for each of the
  46 // accelerometers present on the device.
  47 class CHROMEOS_EXPORT AccelerometerUpdate {
  48  public:
  49   AccelerometerUpdate();
  50   ~AccelerometerUpdate();
  51
  52   // Returns true if |source| has a valid value in this update.
  53   bool has(AccelerometerSource source) const { return data_[source].present; }
  54
  55   // Returns the last known value for |source|.
  56   const AccelerometerReading& get(AccelerometerSource source) const {
  57     return data_[source];
  58   }
  59
  60   void Set(AccelerometerSource source, float x, float y, float z) {
  61     data_[source].present = true;
  62     data_[source].x = x;
  63     data_[source].y = y;
  64     data_[source].z = z;
  65   }
  66
  67  protected:
  68   AccelerometerReading data_[ACCELEROMETER_SOURCE_COUNT];
  69
  70  private:
  71   DISALLOW_COPY_AND_ASSIGN(AccelerometerUpdate);
  72 };
  73
  74 }  // namespace chromeos
  75
  76 #endif  // CHROMEOS_ACCELEROMETER_ACCELEROMETER_TYPES_H_