Blackberry: Use the rotation matrix as the compass source

This fixes the direction flipping over when holding the device
upside-down.

Change-Id: I57bac63208d475d4091b47593b9768613eea30b0
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>
Reviewed-by: Adam Parco <aparco@rim.com>
Reviewed-by: Lorn Potter <lorn.potter@nokia.com>

1 files changed, 82 insertions, 0 deletions

diff --git a/src/plugins/sensors/blackberry/bbutil.cpp b/src/plugins/sensors/blackberry/bbutil.cpp
new file mode 100644
index 00000000..c01c6303
--- /dev/null
+++ b/src/plugins/sensors/blackberry/bbutil.cpp
@@ -0,0 +1,82 @@
+/****************************************************************************
+**
+** Copyright (C) 2012 Research In Motion
+** Contact: http://www.qt-project.org/
+**
+** This file is part of the QtSensors module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** GNU Lesser General Public License Usage
+** This file may be used under the terms of the GNU Lesser General Public
+** License version 2.1 as published by the Free Software Foundation and
+** appearing in the file LICENSE.LGPL included in the packaging of this
+** file. Please review the following information to ensure the GNU Lesser
+** General Public License version 2.1 requirements will be met:
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights. These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU General
+** Public License version 3.0 as published by the Free Software Foundation
+** and appearing in the file LICENSE.GPL included in the packaging of this
+** file. Please review the following information to ensure the GNU General
+** Public License version 3.0 requirements will be met:
+** http://www.gnu.org/copyleft/gpl.html.
+**
+** Other Usage
+** Alternatively, this file may be used in accordance with the terms and
+** conditions contained in a signed written agreement between you and Nokia.
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+#include "bbutil.h"
+
+#include <QtCore/qmath.h>
+
+namespace BbUtil {
+
+static float getMatrixElement(const float matrix[3*3], int index0, int index1)
+{
+    return matrix[index0 * 3 + index1];
+}
+
+void matrixToEulerZXY(const float matrix[3*3],
+                      float &thetaX, float &thetaY, float& thetaZ)
+{
+    thetaX = asin( getMatrixElement(matrix, 2, 1));
+    if ( thetaX < M_PI_2 ) {
+        if ( thetaX > -M_PI_2 ) {
+            thetaZ = atan2( -getMatrixElement(matrix, 0, 1),
+                             getMatrixElement(matrix, 1, 1) );
+            thetaY = atan2( -getMatrixElement(matrix, 2, 0),
+                             getMatrixElement(matrix, 2, 2) );
+        } else {
+            // Not a unique solution
+            thetaZ = -atan2( getMatrixElement(matrix, 0, 2),
+                             getMatrixElement(matrix, 0, 0) );
+            thetaY = 0.0;
+        }
+    } else {
+        // Not a unique solution
+        thetaZ = atan2( getMatrixElement(matrix, 0, 2),
+                        getMatrixElement(matrix, 0, 0) );
+        thetaY = 0.0;
+    }
+}
+
+qreal radiansToDegrees(qreal radians)
+{
+    static const qreal radToDeg = 180.0f / M_PI;
+    return radians * radToDeg;
+}
+
+}