How to convert Yaw,Roll & Pitch values to (x,y) coordinates?

Question

Hi In my app I need to create an gyroscope.So for this I am using following code.

public class AccessGyroscope extends Activity implements SensorEventListener
{
    private TextView tv;
    private SensorManager sManager;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) 
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        tv = (TextView) findViewById(R.id.tv);
        sManager = (SensorManager) getSystemService(SENSOR_SERVICE);
    }

    @Override
    protected void onResume() 
    {
        super.onResume();
        sManager.registerListener(this, sManager.getDefaultSensor(Sensor.TYPE_ORIENTATION),SensorManager.SENSOR_DELAY_FASTEST);
    }

    @Override
    protected void onStop() 
    {
        sManager.unregisterListener(this);
        super.onStop();
    }

    @Override
    public void onAccuracyChanged(Sensor arg0, int arg1) 
    {
    }

    @Override
    public void onSensorChanged(SensorEvent event) 
    {
        if (event.accuracy == SensorManager.SENSOR_STATUS_UNRELIABLE)
        {
            return;
        }

        tv.setText("Orientation X (Roll) :"+ Float.toString(event.values[2]) +"\n"+
                   "Orientation Y (Pitch) :"+ Float.toString(event.values[1]) +"\n"+
                   "Orientation Z (Yaw) :"+ Float.toString(event.values[0]));
    }
}

I can get the Yaw,Roll & Pitch values but I want to show this in 2d plane. Basically I want view like this .

The red dot should move according to the orientation of device. I can work on canvas to prepare that view.But what I really want is those coordinates related to Yaw,Roll & Pitch values.

Please help

Answer 1

Finally I found the answer.

First instead of using TYPE_ORIENTATION I used TYPE_GRAVITY.

Here is my Complete code.

Code for my custom view is..

public class GyroscopeView extends View
{
    private final static String TAG = "GyroscopeView";

    private float bearing;
    float pitch = 0;
    float roll = 0;

    private Paint paintOuter;
    private Paint paintInner;
    private Paint paintDot;

    float pointX, pointY;
    float dotX, dotY;
    int radius;

    public GyroscopeView(Context context, AttributeSet attrs, int defStyle)
    {
        super(context, attrs, defStyle);
        // TODO Auto-generated constructor stub
        initCompassView();
    }

    public GyroscopeView(Context context, AttributeSet attrs)
    {
        super(context, attrs);
        // TODO Auto-generated constructor stub
        initCompassView();
    }

    public GyroscopeView(Context context)
    {
        super(context);
        // TODO Auto-generated constructor stub
        initCompassView();
    }

    protected void initCompassView()
    {
        setFocusable(true);

        Resources r = this.getResources();

        paintOuter = new Paint(Paint.ANTI_ALIAS_FLAG);
        paintOuter.setColor(Color.WHITE);
        paintOuter.setStrokeWidth(1);
        paintOuter.setStyle(Paint.Style.FILL_AND_STROKE);

        paintInner = new Paint(Paint.ANTI_ALIAS_FLAG);
        paintInner.setColor(Color.BLUE);
        paintInner.setStrokeWidth(1);
        paintInner.setStyle(Paint.Style.STROKE);

        paintDot = new Paint(Paint.ANTI_ALIAS_FLAG);
        paintDot.setColor(Color.RED);
        paintDot.setStrokeWidth(1);
        paintDot.setStyle(Paint.Style.FILL_AND_STROKE);

    }

    @Override
    protected void onDraw(Canvas canvas)
    {
        // TODO Auto-generated method stub
        super.onDraw(canvas);

        int px = getMeasuredWidth() / 2;
        int py = getMeasuredHeight() / 2;
        radius = Math.min(px, py);

        pointX = px;
        pointY = py;

        canvas.drawCircle(pointX, pointY, radius, paintOuter);

        canvas.drawCircle(pointX, pointY, 40, paintInner);
        canvas.drawCircle(dotX, dotY, 5, paintDot);

    }

    void update(float z, float yy, float xx)
    {

        if (yy > 0)
        {
            dotY = pointY - ((1 - yy) * z);
        } else
        {
            dotY = pointY + ((1 - yy) * z);
        }
        if (xx > 0)
        {
            dotX = pointX - ((1 - xx) * z);
        } else
        {
            dotX = pointX + ((1 - xx) * z);
        }
        invalidate();
    }

Here is my Activiy Code.

public class GyroscopeActivity extends Activity
{
    GyroscopeView gyroscopeView;
    SensorManager sensorManager;

    float[] gValues = new float[3];


    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.gyroscope);

         gyroscopeView = (GyroscopeView) findViewById(R.id.gyroscope_view);
        initSensor();
    }

    void initSensor()
    {
        sensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
    }

    @Override
    protected void onResume()
    {
        super.onResume();
        Sensor sensorGyroscope = sensorManager.getDefaultSensor(Sensor.TYPE_GRAVITY);
        sensorManager.registerListener(sensorGyroListener, sensorGyroscope, SensorManager.SENSOR_DELAY_UI);
    }

    @Override
    protected void onStop()
    {
        sensorManager.unregisterListener(sensorGyroListener);
        super.onStop();
    }

    private final SensorEventListener sensorGyroListener = new SensorEventListener()
    {
        public void onSensorChanged(SensorEvent event)
        {
            if (event.sensor.getType() == Sensor.TYPE_GRAVITY)
                gValues = event.values;

            gyroscopeView.update(gValues[0], gValues[1], gValues[2]);
        }

        public void onAccuracyChanged(Sensor sensor, int accuracy)
        {
        }
    };

Hope this will help someone.