49 lines
2 KiB
Protocol Buffer
49 lines
2 KiB
Protocol Buffer
|
// @file sns_game_rv.proto
|
||
|
|
//
|
||
|
|
// Defines the API for Game Rotation Vector sensors
|
||
|
|
//
|
||
|
|
// Copyright (c) 2017-2018 Qualcomm Technologies, Inc.
|
||
|
|
// All Rights Reserved.
|
||
|
|
// Confidential and Proprietary - Qualcomm Technologies, Inc.
|
||
|
|
|
||
|
|
syntax = "proto2";
|
||
|
|
import "sns_std_sensor.proto";
|
||
|
|
|
||
|
|
// A GameRV sensor reports the orientation of the device relative to an
|
||
|
|
// unspecified coordinates frame. It is obtained by integration of
|
||
|
|
// accelerometer and gyroscope readings. Therefore the Y axis doesn't point
|
||
|
|
// north but instead to an arbitrary reference.
|
||
|
|
//
|
||
|
|
// ## GameRV sensor attributes:
|
||
|
|
// 1. SNS_STD_SENSOR_ATTRID_TYPE is "game_rv"
|
||
|
|
//
|
||
|
|
// ## Request Message: sns_std_sensor_config
|
||
|
|
// sns_std_sensor_config::sample_rate is used to specify the sampling rate (Hz)
|
||
|
|
// of the GameRV sensor. Sensor will generate data events at this rate.
|
||
|
|
//
|
||
|
|
// ## Event Message: sns_std_sensor_event
|
||
|
|
// Output of the GameRV sensor will be populated in sns_std_sensor_event
|
||
|
|
//
|
||
|
|
// The orientation is represented by the rotation necessary to align
|
||
|
|
// the coordinate frame with the device's coordinates. That is,
|
||
|
|
// applying the rotation to the world frame (X,Y,Z) would align them with
|
||
|
|
// the device coordinates (x,y,z).
|
||
|
|
//
|
||
|
|
// The rotation can be seen as rotating the device by an angle theta around an
|
||
|
|
// axis rot_axis to go from the reference device orientation to the current
|
||
|
|
// device orientation. The rotation is encoded as the four unitless x, y, z, w
|
||
|
|
// components of a unit quaternion:
|
||
|
|
// sns_std_sensor_event::data[0] = rot_axis.x*sin(theta/2)
|
||
|
|
// sns_std_sensor_event::data[1] = rot_axis.y*sin(theta/2)
|
||
|
|
// sns_std_sensor_event::data[2] = rot_axis.z*sin(theta/2)
|
||
|
|
// sns_std_sensor_event::data[3] = cos(theta/2)
|
||
|
|
//
|
||
|
|
// Where:
|
||
|
|
// - the x, y and z fields of rot_axis are the East-North-Up coordinates
|
||
|
|
// of a unit length vector representing the rotation axis
|
||
|
|
// - theta is the rotation angle
|
||
|
|
//
|
||
|
|
// sns_std_sensor_event::status specifies the reliability of the sample value
|
||
|
|
// value is of type sns_std_sensor_sample_status. see sns_std_sensor.proto for
|
||
|
|
// details.
|