Qt繪制垂直文本drawText

        painter.drawText(800-ui->lineEdit_right->text().toInt(),
                         ui->lineEdit_top->text().toInt()+70, 12, 50,
                         Qt::AlignTop | Qt::TextSingleLine | Qt::TextWordWrap,
                         "白存根");

        painter.drawText(800-ui->lineEdit_right->text().toInt(),
                         ui->lineEdit_top->text().toInt()+125, 12, 50,
                         Qt::AlignTop | Qt::TextSingleLine | Qt::TextWordWrap,
                         "藍倉庫");

        painter.drawText(800-ui->lineEdit_right->text().toInt(),
                         ui->lineEdit_top->text().toInt()+180, 12, 50,
                         Qt::AlignTop | Qt::TextSingleLine | Qt::TextWordWrap,
                         "紅財務");
        painter.drawText(800-ui->lineEdit_right->text().toInt(),
                         ui->lineEdit_top->text().toInt()+235, 12, 50,
                         Qt::AlignTop | Qt::TextSingleLine | Qt::TextWordWrap,
                         "黃客戶");

還有一種是整行文字旋轉90度。

    painter.rotate(90);
    painter.drawText(y-30, -x, "電流值");
 
    painter.rotate(180);
    painter.drawText(-y-6, 20, "電壓值");