Android Tutorial Orientation and accelerometer

Jim Brown said:

Hello Erel

The orientation sensor seems to have an impact on the overall timing of an app. It seems to steal quite a bit of operation time
Could you look at adding options to set the polling rate?

Have a look at this example to see what I mean
Here, a ball is set to roll when the phone is tilted (NOTE: operate in landcape mode). On my Samsung Galaxy S there are notable delays as the ball travels
I have set the timer to 10ms interval in order to allow some leeway for the orientation sensor but there is still a significant impact when polling the sensor

B4X:

'AccelBall
Sub Process_Globals
    Dim Orientation As PhoneOrientation
   Dim time As Timer
End Sub

Sub Globals
   Dim can As Canvas
   Dim ballx,bally,ballsize As Float
   Dim targety As Float
End Sub

Sub Activity_Create(FirstTime As Boolean)
   ballx=80 : bally=Activity.Height-Activity.Height/2
   ballsize=42 : targety=bally
   can.Initialize(Activity)
   time.Initialize("Timer1",10)
End Sub

Sub Activity_Resume
    Orientation.StartListening("Orientation") 
   time.Enabled=True
End Sub

Sub Activity_Pause (UserClosed As Boolean)
    Orientation.StopListening
   time.Enabled=False
End Sub

Sub Timer1_Tick
   can.DrawColor(Colors.Black)
   bally=bally+(targety-bally)/2.0
   can.DrawLine(ballx,0,ballx,Activity.Height,Colors.Red,1.0)
   can.DrawCircle(ballx+ballsize,bally,ballsize,Colors.White,True,0.0)
   Activity.Invalidate
End Sub

Sub Orientation_OrientationChanged (Azimuth As Float, Pitch As Float, Roll As Float)
   targety=targety-Pitch
   If targety<ballsize Then targety=ballsize
   If targety>(Activity.Height-ballsize) Then targety=(Activity.Height-ballsize)
End Sub

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Erel said:

You should try to only refresh the parts required.

Refreshing the whole screen each time can be done. In your code you also drew the whole screen each tick.

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Is there a way to get a better light sensor reading from the phone?

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Is it coming from bad sensors?

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what are the units for the accelerometer? m/s²

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Erel said:

The attached program displays the values of the different sensors:

It creates a PhoneSensors object for each type of sensor.
As you can see in the attached code, two Maps are used to hold the phone sensors and the other required data. This way there is no need to write any duplicate code.

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