MICROSOFT_PRESS_EBOOK_PROGRAMMING_WINDOWS_8_APPS_WITH_HTML_CSS_AND_JAVASCRIPT_PDF

Orientation sensor provides a simple interpretation of how the device is oriented in relation to its
default position, rounding everything off, as it were, to the nearest 90-degree quadrant. The full
Orientation sensor, on the other hand, combines gyrometer, accelerometer, and compass data to
provide an exact 3D orientation matrix that is much more precise but much more oriented (if I might
make the pun!) to advanced scenarios than simply needing to know whether the device is upside-down
or rightside-up.
Because all of these sensors are very similar in how they work (which is intentional, with the
exception of the Simple Orientation sensor, which is intentionally dissimilar!), I want to show the general
pattern of the sensor APIs rather than explicit examples for each. Such examples are readily available in
these SDK samples: Accelerometer, Compass, Gyrometer, Inclinometer, Light Sensor, and
OrientationSensor.
The usage pattern is as follows, with the particulars summarized in the table that follows:
• Obtain a sensor object via Windows.Devices.Sensors..getDefault().
• Call that object’s getCurrentReading to obtain a one-time reading.
• For ongoing readings, configure the object’s minimumReportInterval and reportInterval
properties (both in milliseconds) and listen to the object’s readingchanged event. Your handler
will receive a reading object of an appropriate type in response. As with geolocation, setting
these values wisely will help optimize battery life by avoiding excess electrons flying through the
sensors!
Sensor Name
(Windows.Devices.Sensors.)
Accelerometer
Added Members
Event: shaken (event
args contains only a
timestamp property)
Reading Type
(Windows.Devices.Sensors)
AccelerometerReading
Reading Properties (timestamp
is a Date; all others are Numbers
unless noted)
accelerationX (G’s), accelerationY,
accelerationZ, timestamp
Compass n/a CompassReading headingMagneticNorth (degrees),
headingTrueNorth, timestamp
Gyrometer n/a GyrometerReading angularVelocityX (degrees/sec),
angularVelocityY,
angularVelocityZ, timestamp
Inclinometer n/a InclinometerReading pitchDegrees (degrees),
rollDegrees (degrees), yawDegrees
(degrees), timestamp
LightSensor n/a LightSensorReading illuminenceInLux (lux), timestamp
OrientationSensor n/a OrientationSensorReading quaternion, (SensorQuaternion
containing w, x, y, and z properties)
rotationMatrix
(Sensor-RotationMatrix containing
m11, m12, m13, m21, m22, m23,
m31, m32, m33 properties),
timestamp
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