pathdeform.cpp

qt类库是非微软类库

    if (preferImage()) {
        m_lens_image = QImage(bounds.size(), QImage::Format_ARGB32_Premultiplied);
        m_lens_image.fill(0);
        painter.begin(&m_lens_image);
    } else {
        m_lens_pixmap = QPixmap(bounds.size());
        m_lens_pixmap.fill(QColor(0, 0, 0, 0));
        painter.begin(&m_lens_pixmap);
    }

    QRadialGradient gr(rad, rad, rad, 3 * rad / 5, 3 * rad / 5);
    gr.setColorAt(0.0, QColor(255, 255, 255, 191));
    gr.setColorAt(0.2, QColor(255, 255, 127, 191));
    gr.setColorAt(0.9, QColor(150, 150, 200, 63));
    gr.setColorAt(0.95, QColor(0, 0, 0, 127));
    gr.setColorAt(1, QColor(0, 0, 0, 0));
    painter.setRenderHint(QPainter::Antialiasing);
    painter.setBrush(gr);
    painter.setPen(Qt::NoPen);
    painter.drawEllipse(0, 0, bounds.width(), bounds.height());
}


void PathDeformRenderer::setAnimated(bool animated)
{
    m_animated = animated;

    if (m_animated) {
//         m_fpsTimer.start(1000, this);
//         m_fpsCounter = 0;
        m_repaintTimer.start(25, this);
        m_repaintTracker.start();
    } else {
//         m_fpsTimer.stop();
        m_repaintTimer.stop();
    }
}

void PathDeformRenderer::timerEvent(QTimerEvent *e)
{

    if (e->timerId() == m_repaintTimer.timerId()) {

        if (QLineF(QPointF(0,0), m_direction).length() > 1)
            m_direction *= 0.995;
        double time = m_repaintTracker.restart();

        QRect rectBefore = circle_bounds(m_pos, m_radius, m_fontSize);

        double dx = m_direction.x();
        double dy = m_direction.y();
        if (time > 0) {
            dx = dx * time * .1;
            dy = dy * time * .1;
        }

        m_pos += QPointF(dx, dy);



        if (m_pos.x() - m_radius < 0) {
            m_direction.setX(-m_direction.x());
            m_pos.setX(m_radius);
        } else if (m_pos.x() + m_radius > width()) {
            m_direction.setX(-m_direction.x());
            m_pos.setX(width() - m_radius);
        }

        if (m_pos.y() - m_radius < 0) {
            m_direction.setY(-m_direction.y());
            m_pos.setY(m_radius);
        } else if (m_pos.y() + m_radius > height()) {
            m_direction.setY(-m_direction.y());
            m_pos.setY(height() - m_radius);
        }

#ifdef QT_OPENGL_SUPPORT
        if (usesOpenGL()) {
            update();
        } else
#endif
        {
            QRect rectAfter = circle_bounds(m_pos, m_radius, m_fontSize);
            update(rectAfter | rectBefore);
            QApplication::syncX();
        }
    }
//     else if (e->timerId() == m_fpsTimer.timerId()) {
//         printf("fps: %d\n", m_fpsCounter);
//         emit frameRate(m_fpsCounter);
//         m_fpsCounter = 0;

//     }
}

void PathDeformRenderer::mousePressEvent(QMouseEvent *e)
{
    setDescriptionEnabled(false);

    m_repaintTimer.stop();
    m_offset = QPointF();
    if (QLineF(m_pos, e->pos()).length() <= m_radius)
        m_offset = m_pos - e->pos();

    mouseMoveEvent(e);
}

void PathDeformRenderer::mouseReleaseEvent(QMouseEvent *e)
{
    if (e->buttons() == Qt::NoButton && m_animated) {
        m_repaintTimer.start(10, this);
        m_repaintTracker.start();
    }
}

void PathDeformRenderer::mouseMoveEvent(QMouseEvent *e)
{
    QRect rectBefore = circle_bounds(m_pos, m_radius, m_fontSize);
    if (e->type() == QEvent::MouseMove) {
        QLineF line(m_pos, e->pos() + m_offset);
        line.setLength(line.length() * .1);
        QPointF dir(line.dx(), line.dy());
        m_direction = (m_direction + dir) / 2;
    }
    m_pos = e->pos() + m_offset;
#ifdef QT_OPENGL_SUPPORT
    if (usesOpenGL()) {
        update();
    } else
#endif
    {
        QRect rectAfter = circle_bounds(m_pos, m_radius, m_fontSize);
        update(rectBefore | rectAfter);
    }
}

QPainterPath PathDeformRenderer::lensDeform(const QPainterPath &source, const QPointF &offset)
{
    QPainterPath path;
    path.addPath(source);

    double flip = m_intensity / 100.0;

    for (int i=0; i<path.elementCount(); ++i) {
        const QPainterPath::Element &e = path.elementAt(i);

        double x = e.x + offset.x();
        double y = e.y + offset.y();

        double dx = x - m_pos.x();
        double dy = y - m_pos.y();
        double len = m_radius - sqrt(dx * dx + dy * dy);

        if (len > 0) {
            path.setElementPositionAt(i,
                                      x + flip * dx * len / m_radius,
                                      y + flip * dy * len / m_radius);
        } else {
            path.setElementPositionAt(i, x, y);
        }

    }

    return path;
}


void PathDeformRenderer::paint(QPainter *painter)
{
    int pad_x = 5;
    int pad_y = 5;

    int skip_x = qRound(m_pathBounds.width() + pad_x + m_fontSize/2);
    int skip_y = qRound(m_pathBounds.height() + pad_y);

    painter->setPen(Qt::NoPen);
    painter->setBrush(Qt::black);

    QRectF clip(painter->clipPath().boundingRect());

    int overlap = pad_x / 2;

    for (int start_y=0; start_y < height(); start_y += skip_y) {

        if (start_y > clip.bottom())
            break;

        int start_x = -overlap;
        for (; start_x < width(); start_x += skip_x) {

            if (start_y + skip_y >= clip.top() &&
                start_x + skip_x >= clip.left() &&
                start_x <= clip.right()) {
                for (int i=0; i<m_paths.size(); ++i) {
                    QPainterPath path = lensDeform(m_paths[i], QPointF(start_x, start_y));
                    painter->drawPath(path);
                }
            }
        }
        overlap = skip_x - (start_x - width());

    }

    if (preferImage()) {
        painter->drawImage(m_pos - QPointF(m_radius + LENS_EXTENT, m_radius + LENS_EXTENT),
                           m_lens_image);
    } else {
        painter->drawPixmap(m_pos - QPointF(m_radius + LENS_EXTENT, m_radius + LENS_EXTENT),
                            m_lens_pixmap);
    }
}



void PathDeformRenderer::setRadius(int radius)
{
    double max = qMax(m_radius, (double)radius);
    m_radius = radius;
    generateLensPixmap();
    if (!m_animated || m_radius < max) {
#ifdef QT_OPENGL_SUPPORT
        if (usesOpenGL()) {
            update();
        } else
#endif
        {
            update(circle_bounds(m_pos, max, m_fontSize));
        }
    }
}

void PathDeformRenderer::setIntensity(int intensity)
{
    m_intensity = intensity;
    if (!m_animated) {
#ifdef QT_OPENGL_SUPPORT
        if (usesOpenGL()) {
            update();
        } else
#endif
        {
            update(circle_bounds(m_pos, m_radius, m_fontSize));
        }
    }
}