node-l8smartlight

Class: AccelerationStream

AccelerationStream

new AccelerationStream(l8, samplingRate)

AccelerationStream.js, line 51

Time based stream of acceleration data from the L8.

The stream is an object mode stream. It therefore does not return a buffer if read, but one Acceleration data struct at a time. The data structure is identical with the one you would get from the L8#getAcceleration method.

The L8 only provides the Acceleration information if they are polled. This stream takes care of polling the data at a given sampling rate and providing it to you in an easily accessible way.

The stream automatically takes care of starting and stopping the data polling once a listener is connected or disconnected. Therefore you do not need to take care of this nasty business yourself.

The Stream needs an instance of the L8 class to attach to, as well as an optional samplingRate_. The sampling rate tells the system which timeframe (in msec) should be waited between two data polls. If none is given 100 msec is assumed by default.

In order to utilize the Stream simply wrap it around an L8 instance and attach to the corresponding Stream event handlers:

Name Type Description
l8 L8

Instance of the L8 to attach to.
samplingRate int optional
Examples
 var l8 = //...

 var acceleration = new AccelerationStream(l8, 200);
 acceleration.on("data", function(data) {
     // Do something with each part of the acceleration data here.
 });

Alternatively the convenience function L8#createAccelerationStream can be used to get an already connected stream directly from an L8 instance

 var l8 = //...
 var acceleration = l8.createAccelerationStream(200);
 acceleration.on("data", function(data) {
     // Do something with each part of the acceleration data here.
 });

Members

privatecooldown_boolean

Status flag indicating whether the stream is in cooldown mode, aka. if it is currently waiting for the next sampling interval to occur.

privatel8_L8

Instance of the L8 to access for acceleration data

privaterequested_boolean

Status flag indicating whether a request to read a new acceleration data package was issued during the current cooldown mode

privatesamplingRate_Number

Sampling rate which defines in which interval the data is polled from the L8

Methods

private_read()

AccelerationStream.js, line 147

Triggered by the stream API in case the read buffer needs to be filled with information.

privateonResponse_(error, data)

AccelerationStream.js, line 123

Callback invoked each time acceleration data has been read from the L8

The information is retrieved directly from the getAcceleration method.

Name Type Description
error String nullable
data Object

privatepoll_()

AccelerationStream.js, line 110

Poll the acceleration information from the L8.

After the polling is complete the AccelerationStream#onResponse_ method will be invoked as callback.