diff options
author | BogDan Vatra <bogdan@kde.org> | 2019-04-02 14:00:37 +0300 |
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committer | BogDan Vatra <bogdan@kdab.com> | 2019-04-11 06:52:45 +0000 |
commit | 2c9fc2c1a197b84ba9ef3dc4e586a77a18c3dcc5 (patch) | |
tree | 38ac45eb44b585e47542c7b6df20088388836283 /src/plugins/sensors/android/androidmagnetometer.cpp | |
parent | f528104474dd74e34ea6a01da096e7c31730c01a (diff) |
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>
Diffstat (limited to 'src/plugins/sensors/android/androidmagnetometer.cpp')
-rw-r--r-- | src/plugins/sensors/android/androidmagnetometer.cpp | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/src/plugins/sensors/android/androidmagnetometer.cpp b/src/plugins/sensors/android/androidmagnetometer.cpp new file mode 100644 index 00000000..ec663c0b --- /dev/null +++ b/src/plugins/sensors/android/androidmagnetometer.cpp @@ -0,0 +1,67 @@ +/**************************************************************************** +** +** Copyright (C) 2019 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 "androidmagnetometer.h" + +AndroidMagnetometer::AndroidMagnetometer(int type, QSensor *sensor, QObject *parent) + : SensorEventQueue<QMagnetometerReading>(type, sensor, parent) +{} + +void AndroidMagnetometer::dataReceived(const ASensorEvent &event) +{ + const auto &mag = event.magnetic; + qreal accuracy = mag.status == ASENSOR_STATUS_NO_CONTACT ? 0 : mag.status / 3.0; + // check https://developer.android.com/reference/android/hardware/SensorEvent.html#sensor.type_magnetic_field: + // Android uses micro-Tesla, Qt uses Tesla + qreal x = qreal(mag.x) / 1e6; + qreal y = qreal(mag.y) / 1e6; + qreal z = qreal(mag.z) / 1e6; + if (sensor()->skipDuplicates() && qFuzzyCompare(accuracy, m_reader.calibrationLevel()) && + qFuzzyCompare(x, m_reader.x()) && + qFuzzyCompare(y, m_reader.y()) && + qFuzzyCompare(z, m_reader.z())) { + return; + } + m_reader.setCalibrationLevel(accuracy); + m_reader.setTimestamp(uint64_t(event.timestamp / 1000)); + m_reader.setX(x); + m_reader.setY(y); + m_reader.setZ(z); + newReadingAvailable(); +} |