目标
![]()
关键代码
CRulerDrawer::CRulerDrawer(QPainter& painter, QRect rect, int scalePercent) : m_painter(painter), m_rect(rect), m_scalePercent(scalePercent) { m_palette = qApp->palette(); m_scaleUnitSize = PixelRuler::Instance()->GetScaleUnitSize(); } void CRulerDrawer::Draw(ScaleDirection direction, bool drawText) { switch (direction) { case CRulerDrawer::Top: DrawHorizontalScale(true, drawText); break; case CRulerDrawer::Bottom: DrawHorizontalScale(false, drawText); break; case CRulerDrawer::Left: DrawVerticalScale(true, drawText); break; case CRulerDrawer::Right: DrawVerticalScale(false, drawText); break; } } void CRulerDrawer::DrawHorizontalScale(int top, bool drawText) { m_painter.save(); //绘制水平标尺 int x_pos{ 0 }; //水平刻度 m_painter.setPen(QPen(m_palette.color(QPalette::Text))); //绘制刻度 int y_pos_start; if (top) y_pos_start = 0; else y_pos_start = m_rect.height(); while (DPI(x_pos) <= m_rect.width() - 2 * SCALE_MARGIN) { int line_length; //刻度的长度 if (x_pos % (m_scaleUnitSize * m_scaleUnitSize) == 0) //刻度值为100的倍数时绘制刻度的长度为10像素 line_length = DPI(10); else if (x_pos % (m_scaleUnitSize * m_scaleUnitSize / 2) == 0) //刻度值为50的倍数时绘制刻度的长度为8像素 line_length = DPI(8); else line_length = DPI(5); int y_pos_end; if (top) y_pos_end = y_pos_start + line_length; else y_pos_end = y_pos_start - line_length; m_painter.drawLine(QPoint(DPI(x_pos) + SCALE_MARGIN - 1, y_pos_start), QPoint(DPI(x_pos) + SCALE_MARGIN - 1, y_pos_end)); //画刻度上的文本 if (drawText && x_pos % (m_scaleUnitSize * m_scaleUnitSize) == 0) //当刻度值为100的倍数时显示刻度值 { QString str = QString::number(x_pos); QSize str_size = m_painter.fontMetrics().size(Qt::TextSingleLine, str); int y_pos_text; if (top) y_pos_text = DPI(12); else y_pos_text = y_pos_start - DPI(12) - str_size.height(); QRect rect{ QPoint{ DPI(x_pos) + SCALE_MARGIN - str_size.width() / 2, y_pos_text }, str_size }; m_painter.drawText(rect, str); } x_pos += m_scaleUnitSize; } m_painter.restore(); } void CRulerDrawer::DrawVerticalScale(int left, bool drawText) { m_painter.save(); //绘制垂直标尺 int y_pos{ 0 }; //垂直刻度 m_painter.setPen(QPen(m_palette.color(QPalette::Text))); //绘制刻度 int x_pos_start; if (left) x_pos_start = 0; else x_pos_start = m_rect.width(); while (DPI(y_pos) <= m_rect.height() - 2 * SCALE_MARGIN) { int line_length; //刻度的长度 if (y_pos % (m_scaleUnitSize * m_scaleUnitSize) == 0) //刻度值为100的倍数时绘制刻度的长度为10像素 line_length = DPI(10); else if (y_pos % (m_scaleUnitSize * m_scaleUnitSize / 2) == 0) //刻度值为50的倍数时绘制刻度的长度为8像素 line_length = DPI(8); else line_length = DPI(5); int x_pos_end; if (left) x_pos_end = x_pos_start + line_length; else x_pos_end = x_pos_start - line_length; m_painter.drawLine(QPoint(x_pos_start, DPI(y_pos) + SCALE_MARGIN - 1), QPoint(x_pos_end, DPI(y_pos) + SCALE_MARGIN - 1)); //画刻度上的文本 if (drawText && y_pos % (m_scaleUnitSize * m_scaleUnitSize) == 0) //当刻度值为100的倍数时显示刻度值 { QString str = QString::number(y_pos); QSize str_size = m_painter.fontMetrics().size(Qt::TextSingleLine, str); int x_pos_text; if (left) x_pos_text = DPI(12); else x_pos_text = x_pos_start - DPI(12) - str_size.width(); QRect rect{ QPoint{ x_pos_text, DPI(y_pos) + SCALE_MARGIN - str_size.height() / 2 }, str_size }; m_painter.drawText(rect, str); } y_pos += m_scaleUnitSize; } m_painter.restore(); } int CRulerDrawer::DPI(int pixel) { return pixel * m_scalePercent / 100; }
效果
![]()
创作不易，小小的支持一下吧！
![]()
![]()
