Qt绘制文本二 弯曲排列和旋转效果 弧形路径 正弦函数路径

void WgtText::paintEvent(QPaintEvent *event)

{

    QPainter painter(this);

    QString m_string("abcdefghijklmnopqrstuvwxy");

    int font_size = 15;

    float x0 = font_size * m_string.count() * 0.5;

    int YSize = font_size * m_string.count() * 0.5;

    for(int i=0; i<m_string.count(); i++)

    {

        // 按圆弧函数绘制

        painter.save();

        float tAlpha = i*3.14/m_string.count();

        float tx = YSize*cos(tAlpha) + YSize;

        float ty = YSize*sin(tAlpha);

        painter.translate(tx, ty);    // 文字的位置

        painter.rotate(180*i/(float)(m_string.count())); // 将文字本身旋转

        painter.drawText(QPointF(-10.0, 10.0), QString("%1").arg(m_string[i]));

        painter.restore();

    }

}

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void WgtText::paintEvent(QPaintEvent *event)

{

    QPainter painter(this);

    int font_size = 10;

    // 设置字符间距

    int text_space = 2;

    int wh = height();

    QFont font;

    font.setFamily("Microsoft YaHei");

    // 大小

    font.setPointSize(font_size);

    // 使用字体

    painter.setFont(font);

    static QString m_string("abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz");

    for(int i=0; i<m_string.count(); i++)

    {

        // 按正弦函数绘制

        float tx = (font_size + text_space) * i;

        float ty = sin(tx);

        //压缩y坐标

        ty = wh/2 + ty*(wh/2*0.2);

        painter.drawText(QPointF(tx, ty), QString("%1").arg(m_string[i]));

    }

    return QWidget::paintEvent(event);

}