QPolygon pa(3);
const int cursor = margin + m_position * m_scale;
pa.setPoints(3, cursor - cursorWidth, 16, cursor + cursorWidth, 16, cursor, 10);
QPolygon pa(3);
const int cursor = margin + m_position * m_scale;
pa.setPoints(3, cursor - cursorWidth, 16, cursor + cursorWidth, 16, cursor, 10);