C++ (Cpp) QGraphicsItem::graphicsEffect Examples

Example #1

File: lighting.cpp Project: wpbest/copperspice

void Lighting::animate()
{
    angle += (M_PI / 30);
    qreal xs = 200 * sin(angle) - 40 + 25;
    qreal ys = 200 * cos(angle) - 40 + 25;
    m_lightSource->setPos(xs, ys);

    for (int i = 0; i < m_items.size(); ++i) {
        QGraphicsItem *item = m_items.at(i);
        Q_ASSERT(item);

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

        QPointF delta(item->x() - xs, item->y() - ys);
        effect->setOffset(delta.toPoint() / 30);

        qreal dx = delta.x();
        qreal dy = delta.y();
        qreal dd = sqrt(dx * dx + dy * dy);
        QColor color = effect->color();
        color.setAlphaF(qBound(0.4, 1 - dd / 200.0, 0.7));
        effect->setColor(color);
    }

    m_scene.update();
}

Example #2

File: blurpicker.cpp Project: ismaell/android-qt5-qtbase

void BlurPicker::setIndex(qreal index)
{
    m_index = index;

    qreal baseline = 0;
    for (int i = 0; i < m_icons.count(); ++i) {
        QGraphicsItem *icon = m_icons[i];
        qreal a = ((i + m_index) * 2 * M_PI) / m_icons.count();
        qreal xs = 170 * sin(a);
        qreal ys = 100 * cos(a);
        QPointF pos(xs, ys);
        pos = QTransform().rotate(-20).map(pos);
        pos -= QPointF(40, 40);
        icon->setPos(pos);
        baseline = qMax(baseline, ys);
        static_cast<BlurEffect *>(icon->graphicsEffect())->setBaseLine(baseline);
    }

    scene()->update();
}