Implement elevation gain via barometer.

src/main/java/de/dennisguse/opentracks/services/TrackRecordingService.java

@@ -49,6 +49,7 @@ import de.dennisguse.opentracks.content.sensor.SensorDataSet;
 import de.dennisguse.opentracks.services.handlers.GpsStatusValue;
 import de.dennisguse.opentracks.services.handlers.HandlerServer;
 import de.dennisguse.opentracks.services.sensors.BluetoothRemoteSensorManager;
+import de.dennisguse.opentracks.services.sensors.ElevationSumManager;
 import de.dennisguse.opentracks.services.tasks.AnnouncementPeriodicTaskFactory;
 import de.dennisguse.opentracks.services.tasks.PeriodicTaskExecutor;
 import de.dennisguse.opentracks.stats.TrackStatistics;
@@ -115,6 +116,7 @@ public class TrackRecordingService extends Service implements HandlerServer.Hand
     // The following variables are set when recording:
     private WakeLock wakeLock;
     private BluetoothRemoteSensorManager remoteSensorManager;
+    private ElevationSumManager elevationSumManager;
 
     private TrackStatisticsUpdater trackStatisticsUpdater;
     private TrackPoint lastTrackPoint;
@@ -174,6 +176,11 @@ public class TrackRecordingService extends Service implements HandlerServer.Hand
             remoteSensorManager = null;
         }
 
+        if (elevationSumManager != null) {
+            elevationSumManager.stop(this);
+            elevationSumManager = null;
+        }
+
         // Reverse order from onCreate
         showNotification(false); //TODO Why?
 
@@ -371,6 +378,10 @@ public class TrackRecordingService extends Service implements HandlerServer.Hand
         // Update instance variables
         remoteSensorManager = new BluetoothRemoteSensorManager(this);
         remoteSensorManager.start();
+
+        elevationSumManager = new ElevationSumManager();
+        elevationSumManager.start(this);
+
         lastTrackPoint = null;
         isIdle = false;
 
@@ -456,6 +467,11 @@ public class TrackRecordingService extends Service implements HandlerServer.Hand
             remoteSensorManager.stop();
             remoteSensorManager = null;
         }
+        if (elevationSumManager != null) {
+            elevationSumManager.stop(this);
+            elevationSumManager = null;
+        }
+
         lastTrackPoint = null;
 
         handlerServer.stop(this);
@@ -533,6 +549,10 @@ public class TrackRecordingService extends Service implements HandlerServer.Hand
         //TODO Figure out how to avoid loading the lastValidTrackPoint from the database
         TrackPoint lastValidTrackPoint = getLastValidTrackPointInCurrentSegment(track.getId());
 
+        if (elevationSumManager != null) {
+            trackPoint.setElevationGain(elevationSumManager.getElevationGain_m());
+        }
+
         //Storing trackPoint
 
         // Always insert the first segment location
@@ -556,15 +576,19 @@ public class TrackRecordingService extends Service implements HandlerServer.Hand
             insertTrackPoint(track, TrackPoint.createPause());
 
             insertTrackPoint(track, trackPoint);
-            isIdle = false;
+            elevationSumManager.reset();
 
+            isIdle = false;
             lastTrackPoint = trackPoint;
             return;
         }
 
         if (trackPoint.hasSensorData() || distanceToLastTrackLocation >= recordingDistanceInterval) {
             insertTrackPointIfNewer(track, lastTrackPoint);
+
             insertTrackPoint(track, trackPoint);
+            elevationSumManager.reset();
+
             isIdle = false;
 
             lastTrackPoint = trackPoint;
@@ -573,7 +597,10 @@ public class TrackRecordingService extends Service implements HandlerServer.Hand
 
         if (!isIdle && !TrackPointUtils.isMoving(trackPoint)) {
             insertTrackPointIfNewer(track, lastTrackPoint);
+
             insertTrackPoint(track, trackPoint);
+            elevationSumManager.reset();
+
             isIdle = true;
 
             lastTrackPoint = trackPoint;
@@ -582,7 +609,10 @@ public class TrackRecordingService extends Service implements HandlerServer.Hand
 
         if (isIdle && TrackPointUtils.isMoving(trackPoint)) {
             insertTrackPointIfNewer(track, lastTrackPoint);
+
             insertTrackPoint(track, trackPoint);
+            elevationSumManager.reset();
+
             isIdle = false;
 
             lastTrackPoint = trackPoint;
@@ -672,6 +702,17 @@ public class TrackRecordingService extends Service implements HandlerServer.Hand
         }
     }
 
+    /**
+     * Returns the relative elevation gain (since last trackpoint).
+     */
+    Float getElevationGain_m() {
+        if (elevationSumManager == null || !elevationSumManager.isConnected()) {
+            return null;
+        }
+
+        return elevationSumManager.getElevationGain_m();
+    }
+
     private void showNotification(boolean isGpsStarted) {
         if (isRecording()) {
             Intent intent = IntentUtils.newIntent(this, TrackRecordingActivity.class)

src/main/java/de/dennisguse/opentracks/services/TrackRecordingServiceBinder.java

@@ -99,6 +99,11 @@ class TrackRecordingServiceBinder extends android.os.Binder implements TrackReco
         return trackRecordingService.getSensorDataSet();
     }
 
+    @Override
+    public Float getElevationGain_m() {
+        return trackRecordingService.getElevationGain_m();
+    }
+
     @VisibleForTesting
     @Override
     public void setRemoteSensorManager(BluetoothRemoteSensorManager remoteSensorManager) {

src/main/java/de/dennisguse/opentracks/services/TrackRecordingServiceInterface.java

@@ -65,12 +65,19 @@ public interface TrackRecordingServiceInterface {
     Marker.Id insertMarker(String name, String category, String description, String photoUrl);
 
     /**
-     * Gets the current sensor data. Returns null if there is no data.
+     * Gets the current sensor data.
      *
-     * @return SensorDataSet object.
+     * @return SensorDataSet object or null.
      */
     SensorDataSet getSensorData();
 
+    /**
+     * Gets the current elevation gain.
+     *
+     * @return elevation gain in m or null.
+     */
+    Float getElevationGain_m();
+
     @VisibleForTesting
     void setRemoteSensorManager(BluetoothRemoteSensorManager remoteSensorManager);
 

src/main/java/de/dennisguse/opentracks/services/sensors/ElevationSumManager.java

@@ -0,0 +1,102 @@
+package de.dennisguse.opentracks.services.sensors;
+
+import android.content.Context;
+import android.hardware.Sensor;
+import android.hardware.SensorEvent;
+import android.hardware.SensorEventListener;
+import android.hardware.SensorManager;
+import android.util.Log;
+
+import androidx.annotation.VisibleForTesting;
+
+import de.dennisguse.opentracks.util.PressureSensorUtils;
+import de.dennisguse.opentracks.util.UnitConversions;
+
+/**
+ * Estimates the elevation gain and elevation loss using the device's pressure sensor (i.e., barometer).
+ */
+public class ElevationSumManager implements SensorEventListener {
+
+    private static final String TAG = ElevationSumManager.class.getSimpleName();
+
+    private static final int SAMPLING_RATE = 3 * (int) UnitConversions.ONE_SECOND_US;
+
+    private boolean isConnected = false;
+
+    private float lastUsedPressureValue_hPa;
+
+    private float elevationGain_m;
+    private float elevationLoss_m;
+
+    public void start(Context context) {
+        SensorManager sensorManager = (SensorManager) context.getSystemService(Context.SENSOR_SERVICE);
+
+        Sensor pressureSensor = sensorManager.getDefaultSensor(Sensor.TYPE_PRESSURE);
+        if (pressureSensor == null) {
+            Log.w(TAG, "No pressure sensor available.");
+            isConnected = false;
+        }
+
+        isConnected = sensorManager.registerListener(this, pressureSensor, SAMPLING_RATE);
+        lastUsedPressureValue_hPa = Float.NaN;
+        reset();
+    }
+
+    public void stop(Context context) {
+        Log.d(TAG, "Stop");
+
+        SensorManager sensorManager = (SensorManager) context.getSystemService(Context.SENSOR_SERVICE);
+        sensorManager.unregisterListener(this);
+
+        isConnected = false;
+        reset();
+    }
+
+    public boolean isConnected() {
+        return isConnected;
+    }
+
+    public float getElevationGain_m() {
+        return elevationGain_m;
+    }
+
+    public float getElevationLoss_m() {
+        return elevationLoss_m;
+    }
+
+    public void reset() {
+        Log.d(TAG, "Reset");
+        elevationGain_m = 0;
+        elevationLoss_m = 0;
+    }
+
+    @Override
+    public void onAccuracyChanged(Sensor sensor, int accuracy) {
+        Log.w(TAG, "Sensor accuracy changes are (currently) ignored.");
+    }
+
+    @Override
+    public void onSensorChanged(SensorEvent event) {
+        onSensorValueChanged(event.values[0]);
+    }
+
+    @VisibleForTesting
+    void onSensorValueChanged(float value_hPa) {
+        if (Float.isNaN(lastUsedPressureValue_hPa)) {
+            lastUsedPressureValue_hPa = value_hPa;
+            return;
+        }
+
+        PressureSensorUtils.ElevationChange elevationChange = PressureSensorUtils.computeChanges_m(lastUsedPressureValue_hPa, value_hPa);
+        if (elevationChange != null) {
+            if (elevationChange.getElevationChange_m() > 0) {
+                elevationGain_m += elevationChange.getElevationChange_m();
+            } else {
+                elevationLoss_m += elevationChange.getElevationChange_m();
+            }
+            lastUsedPressureValue_hPa = elevationChange.getCurrentSensorValue_hPa();
+        }
+
+        Log.v(TAG, "elevation gain: " + elevationGain_m);
+    }
+}