diff -r 000000000000 -r 1918ee327afb demos/qtdemo/guidecircle.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/demos/qtdemo/guidecircle.cpp	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,88 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the demonstration applications of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, 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.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "guidecircle.h"
+
+static float PI2 = 2*3.1415f;
+
+GuideCircle::GuideCircle(const QRectF &rect, float startAngle, float span, DIRECTION dir, Guide *follows) : Guide(follows)
+{
+    this->radiusX = rect.width() / 2.0;
+    this->radiusY = rect.height() / 2.0;
+    this->posX = rect.topLeft().x();
+    this->posY = rect.topLeft().y();
+    this->spanRad = span * PI2 / -360.0;
+    if (dir == CCW){
+        this->startAngleRad = startAngle * PI2 / -360.0;
+        this->endAngleRad = startAngleRad + spanRad;
+        this->stepAngleRad = this->spanRad / this->length();
+    }
+    else{
+        this->startAngleRad = spanRad + (startAngle * PI2 / -360.0);
+        this->endAngleRad = startAngle * PI2 / -360.0;
+        this->stepAngleRad = -this->spanRad / this->length();
+    }
+}
+
+float GuideCircle::length()
+{
+    return qAbs(this->radiusX * spanRad);
+}
+
+QPointF GuideCircle::startPos()
+{
+    return QPointF((posX + radiusX + radiusX * cos(startAngleRad)) * scaleX,
+                   (posY + radiusY + radiusY * sin(startAngleRad)) * scaleY);
+}
+
+QPointF GuideCircle::endPos()
+{
+    return QPointF((posX + radiusX + radiusX * cos(endAngleRad)) * scaleX,
+                   (posY + radiusY + radiusY * sin(endAngleRad)) * scaleY);
+}
+
+void GuideCircle::guide(DemoItem *item, float moveSpeed)
+{
+    float frame = item->guideFrame - this->startLength;
+    QPointF end((posX + radiusX + radiusX * cos(startAngleRad + (frame * stepAngleRad))) * scaleX,
+                (posY + radiusY + radiusY * sin(startAngleRad + (frame * stepAngleRad))) * scaleY);
+    this->move(item, end, moveSpeed);
+}