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     3 ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).

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    40 ****************************************************************************/

    41 

    42 #include "lighting.h"

    43 

    44 #include <QtGui>

    45 

    46 #ifndef M_PI

    47 #define M_PI 3.14159265358979323846

    48 #endif

    49 

    50 Lighting::Lighting(QWidget *parent): QGraphicsView(parent), angle(0.0)

    51 {

    52     setScene(&m_scene);

    53 

    54     setupScene();

    55 

    56     QTimer *timer = new QTimer(this);

    57     connect(timer, SIGNAL(timeout()), SLOT(animate()));

    58     timer->setInterval(30);

    59     timer->start();

    60 

    61     setRenderHint(QPainter::Antialiasing, true);

    62     setFrameStyle(QFrame::NoFrame);

    63 }

    64 

    65 void Lighting::setupScene()

    66 {

    67     m_scene.setSceneRect(-300, -200, 600, 460);

    68 

    69     QLinearGradient linearGrad(QPointF(-100, -100), QPointF(100, 100));

    70     linearGrad.setColorAt(0, QColor(255, 255, 255));

    71     linearGrad.setColorAt(1, QColor(192, 192, 255));

    72     setBackgroundBrush(linearGrad);

    73 

    74     QRadialGradient radialGrad(30, 30, 30);

    75     radialGrad.setColorAt(0, Qt::yellow);

    76     radialGrad.setColorAt(0.2, Qt::yellow);

    77     radialGrad.setColorAt(1, Qt::transparent);

    78     QPixmap pixmap(60, 60);

    79     pixmap.fill(Qt::transparent);

    80     QPainter painter(&pixmap);

    81     painter.setPen(Qt::NoPen);

    82     painter.setBrush(radialGrad);

    83     painter.drawEllipse(0, 0, 60, 60);

    84     painter.end();

    85 

    86     m_lightSource = m_scene.addPixmap(pixmap);

    87     m_lightSource->setZValue(2);

    88 

    89     for (int i = -2; i < 3; ++i)

    90         for (int j = -2; j < 3; ++j) {

    91             QAbstractGraphicsShapeItem *item;

    92             if ((i + j) & 1)

    93                 item = new QGraphicsEllipseItem(0, 0, 50, 50);

    94             else

    95                 item = new QGraphicsRectItem(0, 0, 50, 50);

    96 

    97             item->setPen(QPen(Qt::black));

    98             item->setBrush(QBrush(Qt::white));

    99             QGraphicsDropShadowEffect *effect = new QGraphicsDropShadowEffect;

   100             effect->setBlurRadius(8);

   101             item->setGraphicsEffect(effect);

   102             item->setZValue(1);

   103             item->setPos(i * 80, j * 80);

   104             m_scene.addItem(item);

   105             m_items << item;

   106         }

   107 

   108 

   109 }

   110 

   111 void Lighting::animate()

   112 {

   113     angle += (M_PI / 30);

   114     qreal xs = 200 * sin(angle) - 40 + 25;

   115     qreal ys = 200 * cos(angle) - 40 + 25;

   116     m_lightSource->setPos(xs, ys);

   117 

   118     for (int i = 0; i < m_items.size(); ++i) {

   119         QGraphicsItem *item = m_items.at(i);

   120         Q_ASSERT(item);

   121         QGraphicsDropShadowEffect *effect = static_cast<QGraphicsDropShadowEffect *>(item->graphicsEffect());

   122         Q_ASSERT(effect);

   123 

   124         QPointF delta(item->x() - xs, item->y() - ys);

   125         effect->setOffset(delta.toPoint() / 30);

   126 

   127         qreal dx = delta.x();

   128         qreal dy = delta.y();

   129         qreal dd = sqrt(dx * dx + dy * dy);

   130         QColor color = effect->color();

   131         color.setAlphaF(qBound(0.4, 1 - dd / 200.0, 0.7));

   132         effect->setColor(color);

   133     }

   134 

   135     m_scene.update();

   136 }

   137