BlackBerry backend: Automatic Axis Remapping

Add a backend specific property named "automaticAxisRemapping" to force
the sensor to modify its coordinate system based on the device native
orientation.

So usable from C++ using 'setProperty("automaticAxisRemapping", true)'
or from QML using 'property var automaticAxisRemapping: true'.

Note it requires QPlatformScreen::nativeOrientation() private API to
find out the device native orientation.

Change-Id: If4c5622fd42c74a55fe6d36966d7f589e612c117
Reviewed-by: Adam Parco <aparco@rim.com>
Reviewed-by: Lincoln Ramsay <lincoln.ramsay@nokia.com>

3 files changed, 78 insertions, 3 deletions

diff --git a/src/plugins/sensors/blackberry/bbrotationsensor.cpp b/src/plugins/sensors/blackberry/bbrotationsensor.cpp
index fe34ea4..28dc49c 100644
--- a/src/plugins/sensors/blackberry/bbrotationsensor.cpp
+++ b/src/plugins/sensors/blackberry/bbrotationsensor.cpp
@@ -42,10 +42,16 @@
 
 #include "bbutil.h"
 #include <QtCore/qmath.h>
+#include <QGuiApplication>
+#include <QScreen>
+#include <qpa/qplatformscreen.h>
 
 BbRotationSensor::BbRotationSensor(QSensor *sensor)
-    : BbSensorBackend<QRotationReading>(devicePath(), SENSOR_TYPE_ROTATION_MATRIX, sensor)
+    : BbSensorBackend<QRotationReading>(devicePath(), SENSOR_TYPE_ROTATION_MATRIX, sensor),
+      m_orientation(Qt::PrimaryOrientation),
+      m_nativeOrientation(Qt::PrimaryOrientation)
 {
+    updateOrientation();
     setDescription(QLatin1String("Device rotation in degrees"));
 }
 
@@ -95,16 +101,46 @@ static void matrixToEulerZXY(const float matrix[3*3],
     }
 }
 
+static void remapMatrix(const float inputMatrix[3*3],
+                        const float mappingMatrix[4],
+                        float outputMatrix[3*3])
+{
+    int i,j,k;
+
+    for (i = 0; i < 3; i++) {
+        for (j = 0; j < 2; j++) { //only goto 2 because last column stays unchanged
+
+            outputMatrix[i*3+j] = 0;
+
+            for (k = 0; k < 2; k++) { //only goto 2 because we know rotation matrix is zero in bottom row
+                outputMatrix[i*3+j] += inputMatrix[i*3+k] * mappingMatrix[k*2+j];
+            }
+        }
+
+        outputMatrix[i*3+2] = inputMatrix[i*3+2];
+    }
+}
+
+
 bool BbRotationSensor::updateReadingFromEvent(const sensor_event_t &event, QRotationReading *reading)
 {
     // sensor_event_t has euler angles for a Z-Y'-X'' system, but the QtMobility API
     // uses Z-X'-Y''.
     // So extract the euler angles using the Z-X'-Y'' system from the matrix.
     float xRad, yRad, zRad;
-    matrixToEulerZXY(event.rotation_matrix, xRad, yRad, zRad);
+
+    if (isAutoAxisRemappingEnabled() && m_orientation!=m_nativeOrientation) {
+        float mappedRotationMatrix[3*3];
+        remapMatrix(event.rotation_matrix, m_mappingMatrix, mappedRotationMatrix);
+        matrixToEulerZXY(mappedRotationMatrix, xRad, yRad, zRad);
+    } else {
+        matrixToEulerZXY(event.rotation_matrix, xRad, yRad, zRad);
+    }
+
     reading->setX(radiansToDegrees(xRad));
     reading->setY(radiansToDegrees(yRad));
     reading->setZ(radiansToDegrees(zRad));
+
     return true;
 }
 
@@ -112,3 +148,33 @@ qreal BbRotationSensor::convertValue(float bbValueInRad)
 {
     return radiansToDegrees(bbValueInRad);
 }
+
+bool BbRotationSensor::isAutoAxisRemappingEnabled() const
+{
+    return sensor()->property("automaticAxisRemapping").toBool();
+}
+
+bool BbRotationSensor::eventFilter(QObject *object, QEvent *event)
+{
+    if (object == QCoreApplication::instance() && event->type() == QEvent::OrientationChange)
+        updateOrientation();
+
+    return BbSensorBackend<QRotationReading>::eventFilter(object, event);
+}
+
+void BbRotationSensor::updateOrientation()
+{
+    QScreen *screen = QGuiApplication::primaryScreen();
+    if (screen) {
+        const QPlatformScreen * const platformScreen = screen->handle();
+        m_nativeOrientation = platformScreen->nativeOrientation();
+        m_orientation = screen->orientation();
+
+        const int rotationAngle = screen->angleBetween(m_nativeOrientation, m_orientation);
+
+        m_mappingMatrix[0] = cos(rotationAngle*M_PI/180);
+        m_mappingMatrix[1] = sin(rotationAngle*M_PI/180);
+        m_mappingMatrix[2] = -sin(rotationAngle*M_PI/180);
+        m_mappingMatrix[3] = cos(rotationAngle*M_PI/180);
+    }
+}
diff --git a/src/plugins/sensors/blackberry/bbrotationsensor.h b/src/plugins/sensors/blackberry/bbrotationsensor.h
index 475ad22..d2fd8a0 100644
--- a/src/plugins/sensors/blackberry/bbrotationsensor.h
+++ b/src/plugins/sensors/blackberry/bbrotationsensor.h
@@ -58,7 +58,16 @@ protected:
     bool addDefaultRange();
     qreal convertValue(float bbValue);
     bool updateReadingFromEvent(const sensor_event_t &event, QRotationReading *reading);
+    bool isAutoAxisRemappingEnabled() const;
 
+    bool eventFilter(QObject *object, QEvent *event);
+
+private:
+    void updateOrientation();
+
+    Qt::ScreenOrientation m_orientation;
+    Qt::ScreenOrientation m_nativeOrientation;
+    float m_mappingMatrix[4];
 };
 
 #endif
diff --git a/src/plugins/sensors/blackberry/blackberry.pro b/src/plugins/sensors/blackberry/blackberry.pro
index c2efb36..1f81e06 100644
--- a/src/plugins/sensors/blackberry/blackberry.pro
+++ b/src/plugins/sensors/blackberry/blackberry.pro
@@ -1,7 +1,7 @@
 load(qt_module)
 
 TARGET = qtsensors_blackberry
-QT = sensors core gui
+QT = sensors core gui gui-private
 DEFINES += QT_NO_CAST_FROM_ASCII QT_NO_CAST_TO_ASCII
 
 load(qt_plugin)