Say hello to Qt Android Sensors based on NDK API

Until Qt 5.9, we had to use JNI way because the NDK sensors API was
introduced in API-16. Starting with Qt 5.9 we can safely use the NDK API
as API_16 is the minimum API supported by Qt.
Using the NDK API instead of JNI boost the performance a lot! The CPU
usage dropped 2 to 4 times, from over 60% using the JNI to less than
20%.

[ChangeLog][Android] Rewrite Qt Android Sensors using NDK
API.

Change-Id: If3e3f1e56973e2a189662912b2a6ebfbd71dee14
Reviewed-by: Lorn Potter <lorn.potter@gmail.com>

1 files changed, 167 insertions, 0 deletions

diff --git a/src/plugins/sensors/android/main.cpp b/src/plugins/sensors/android/main.cpp
new file mode 100644
index 00000000..85853cd2
--- /dev/null
+++ b/src/plugins/sensors/android/main.cpp
@@ -0,0 +1,167 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 BogDan Vatra <bogdan@kde.org>
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtSensors module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <qplugin.h>
+#include <qsensorplugin.h>
+#include <qsensorbackend.h>
+#include <qsensormanager.h>
+#include <qaccelerometer.h>
+#include <qcompass.h>
+#include "androidaccelerometer.h"
+#include "androidcompass.h"
+#include "androidgyroscope.h"
+#include "androidlight.h"
+#include "androidmagnetometer.h"
+#include "androidpressure.h"
+#include "androidproximity.h"
+#include "androidrotation.h"
+#include "androidtemperature.h"
+
+#include "sensormanager.h"
+#include <android/sensor.h>
+
+namespace {
+    const char AndroidCompassId[] = "android.synthetic.compass";
+}
+
+class AndroidSensorPlugin : public QObject, public QSensorPluginInterface, public QSensorBackendFactory
+{
+    Q_OBJECT
+    Q_PLUGIN_METADATA(IID "org.qt-project.Qt.QSensorPluginInterface/1.0" FILE "plugin.json")
+    Q_INTERFACES(QSensorPluginInterface)
+public:
+    void registerSensors() override
+    {
+        bool accelerometer = false;
+        bool magnetometer = false;
+        ASensorList availableSensors;
+        int count = ASensorManager_getSensorList(SensorManager::instance()->manager(), &availableSensors);
+        for (int i = 0; i < count; i++) {
+            int sensor = ASensor_getType(availableSensors[i]);
+            switch (sensor) {
+            case ASENSOR_TYPE_ACCELEROMETER:
+                m_accelerationModes |= AndroidAccelerometer::Accelerometer;
+                QSensorManager::registerBackend(QAccelerometer::type, QByteArray::number(sensor), this);
+                accelerometer = true;
+                break;
+            case ASENSOR_TYPE_GRAVITY:
+                m_accelerationModes |= AndroidAccelerometer::Gravity;
+                break;
+            case ASENSOR_TYPE_LINEAR_ACCELERATION:
+                m_accelerationModes |= AndroidAccelerometer::LinearAcceleration;
+                break;
+            case ASENSOR_TYPE_AMBIENT_TEMPERATURE:
+                QSensorManager::registerBackend(QAmbientTemperatureSensor::type, QByteArray::number(sensor), this);
+                break;
+            case ASENSOR_TYPE_GYROSCOPE:
+                QSensorManager::registerBackend(QGyroscope::type, QByteArray::number(sensor), this);
+                break;
+            case ASENSOR_TYPE_LIGHT:
+                QSensorManager::registerBackend(QLightSensor::type, QByteArray::number(sensor), this);
+                break;
+            case ASENSOR_TYPE_MAGNETIC_FIELD:
+                QSensorManager::registerBackend(QMagnetometer::type, QByteArray::number(sensor), this);
+                magnetometer = true;
+                break;
+            case ASENSOR_TYPE_PRESSURE:
+                QSensorManager::registerBackend(QPressureSensor::type, QByteArray::number(sensor), this);
+                break;
+            case ASENSOR_TYPE_PROXIMITY:
+                QSensorManager::registerBackend(QProximitySensor::type, QByteArray::number(sensor), this);
+                break;
+            case ASENSOR_TYPE_ROTATION_VECTOR:
+                QSensorManager::registerBackend(QRotationSensor::type, QByteArray::number(sensor), this);
+                break;
+
+            case ASENSOR_TYPE_RELATIVE_HUMIDITY:
+            case ASENSOR_TYPE_MAGNETIC_FIELD_UNCALIBRATED:
+            case ASENSOR_TYPE_GAME_ROTATION_VECTOR:
+            case ASENSOR_TYPE_GYROSCOPE_UNCALIBRATED:
+            case ASENSOR_TYPE_SIGNIFICANT_MOTION:
+            case ASENSOR_TYPE_STEP_DETECTOR:
+            case ASENSOR_TYPE_STEP_COUNTER:
+            case ASENSOR_TYPE_GEOMAGNETIC_ROTATION_VECTOR:
+            case ASENSOR_TYPE_HEART_RATE:
+            case ASENSOR_TYPE_POSE_6DOF:
+            case ASENSOR_TYPE_STATIONARY_DETECT:
+            case ASENSOR_TYPE_MOTION_DETECT:
+            case ASENSOR_TYPE_HEART_BEAT:
+            case ASENSOR_TYPE_LOW_LATENCY_OFFBODY_DETECT:
+            case ASENSOR_TYPE_ACCELEROMETER_UNCALIBRATED:
+                break; // ### TODO add backends for missing Android sensors
+            }
+        }
+        if (accelerometer && magnetometer)
+            QSensorManager::registerBackend(QCompass::type, AndroidCompassId, this);
+    }
+
+    QSensorBackend *createBackend(QSensor *sensor) override
+    {
+        if (sensor->identifier() == AndroidCompassId)
+            return new AndroidCompass(sensor);
+
+        int type = sensor->identifier().toInt();
+        switch (type) {
+        case ASENSOR_TYPE_ACCELEROMETER:
+            return new AndroidAccelerometer(m_accelerationModes, sensor);
+        case ASENSOR_TYPE_AMBIENT_TEMPERATURE:
+            return new AndroidTemperature(type, sensor);
+        case ASENSOR_TYPE_GYROSCOPE:
+            return new AndroidGyroscope(type, sensor);
+        case ASENSOR_TYPE_LIGHT:
+            return new AndroidLight(type, sensor);
+        case ASENSOR_TYPE_MAGNETIC_FIELD:
+            return new AndroidMagnetometer(type, sensor);
+        case ASENSOR_TYPE_PRESSURE:
+            return new AndroidPressure(type, sensor);
+        case ASENSOR_TYPE_PROXIMITY:
+            return new AndroidProximity(type, sensor);
+        case ASENSOR_TYPE_ROTATION_VECTOR:
+            return new AndroidRotation(type, sensor);
+        }
+        return nullptr;
+    }
+private:
+    int m_accelerationModes = 0;
+};
+
+Q_IMPORT_PLUGIN (AndroidSensorPlugin) // automatically register the plugin
+
+#include "main.moc"
+