C++ qwtMax函数代码示例

void PreviewPlot2D::onZoomRec(const QMouseEvent& e)
{
    // some shortcuts
    int axl= QwtPlot::yLeft, axb= QwtPlot::xBottom;
 
	// Don't invert any scales which aren't inverted
	int x1 = qwtMin(memPoint.x(), e.pos().x());
    int x2 = qwtMax(memPoint.x(), e.pos().x());
    int y1 = qwtMin(memPoint.y(), e.pos().y());
    int y2 = qwtMax(memPoint.y(), e.pos().y());
        
	// limit selected area to a minimum of 11x11 points
	int lim = 5 - (y2 - y1) / 2;
	if (lim > 0)
	{
		y1 -= lim;
		y2 += lim;
	}
	lim = 5 - (x2 - x1 + 1) / 2;
	if (lim > 0)
	{
		x1 -= lim;
		x2 += lim;
	}
        
	// Set fixed scales
	if(!autoscaleY)
		pPlot->setAxisScale(axl, pPlot->invTransform(axl,y1), pPlot->invTransform(axl,y2));
	if(!autoscaleX)
		pPlot->setAxisScale(axb, pPlot->invTransform(axb,x1), pPlot->invTransform(axb,x2));
	pPlot->replot();
}

/*!
  \return a minimum size hint
*/
QSize QwtScaleWidget::minimumSizeHint() const
{
    const Qt::Orientation o = d_data->scaleDraw->orientation();

    // Border Distance cannot be less than the scale borderDistHint
    // Note, the borderDistHint is already included in minHeight/minWidth
    int length = 0;
    int mbd1, mbd2;
    getBorderDistHint(mbd1, mbd2);
    length += qwtMax( 0, d_data->borderDist[0] - mbd1 );
    length += qwtMax( 0, d_data->borderDist[1] - mbd2 );
    length += d_data->scaleDraw->minLength(
        QPen(Qt::black, d_data->penWidth), font());

    int dim = dimForLength(length, font());
    if ( length < dim )
    {
        // compensate for long titles
        length = dim;
        dim = dimForLength(length, font());
    }

    QSize size(length + 2, dim);
    if ( o == Qt::Vertical )
        size.transpose();

    return size;
}

/*!
  Adjust contents widget and item layout to the size of the viewport().
*/
void QwtLegend::layoutContents()
{
    const QSize visibleSize = d_data->view->viewport()->size();

    const QLayout *l = d_data->view->contentsWidget->layout();
    if ( l && l->inherits("QwtDynGridLayout") )
    {
        const QwtDynGridLayout *tl = (const QwtDynGridLayout *)l;

        const int minW = int(tl->maxItemWidth()) + 2 * tl->margin();

        int w = qwtMax(visibleSize.width(), minW);
        int h = qwtMax(tl->heightForWidth(w), visibleSize.height());

        const int vpWidth = d_data->view->viewportSize(w, h).width();
        if ( w > vpWidth )
        {
            w = qwtMax(vpWidth, minW);
            h = qwtMax(tl->heightForWidth(w), visibleSize.height());
        }

        d_data->view->contentsWidget->resize(w, h);
#if QT_VERSION < 0x040000
        d_data->view->resizeContents(w, h);
#endif
    }
}

/*!
   Calculate the minimum length that is needed to draw the scale

   \param pen Pen that is used for painting backbone and ticks
   \param font Font used for painting the labels

   \sa extent()
*/
int QwtScaleDraw::minLength(const QPen &pen, const QFont &font) const
{
    int startDist, endDist;
    getBorderDistHint(font, startDist, endDist);

    const QwtScaleDiv &sd = scaleDiv();

    const uint minorCount =
        sd.ticks(QwtScaleDiv::MinorTick).count() +
        sd.ticks(QwtScaleDiv::MediumTick).count();
    const uint majorCount =
        sd.ticks(QwtScaleDiv::MajorTick).count();

    int lengthForLabels = 0;
    if ( hasComponent(QwtAbstractScaleDraw::Labels) )
    {
        if ( majorCount >= 2 )
            lengthForLabels = minLabelDist(font) * (majorCount - 1);
    }

    int lengthForTicks = 0;
    if ( hasComponent(QwtAbstractScaleDraw::Ticks) )
    {
        const int pw = qwtMax( 1, pen.width() );  // penwidth can be zero
        lengthForTicks = 2 * (majorCount + minorCount) * pw;
    }

    return startDist + endDist + qwtMax(lengthForLabels, lengthForTicks);
}

int TimelineWidget::transform(double value) const
{
   const double min = qwtMin(mpD->map.s1(), mpD->map.s2());
   const double max = qwtMax(mpD->map.s1(), mpD->map.s2());
   value = qwtMax(qwtMin(value, max), min);
   return mpD->map.transform(value);
}

/*!
   Calculate the width/height that is needed for a
   vertical/horizontal scale.

   The extent is calculated from the pen width of the backbone,
   the major tick length, the spacing and the maximum width/height
   of the labels.

   \param pen Pen that is used for painting backbone and ticks
   \param font Font used for painting the labels

   \sa minLength()
*/
int QwtScaleDraw::extent(const QPen &pen, const QFont &font) const
{
    int d = 0;

    if ( hasComponent(QwtAbstractScaleDraw::Labels) )
    {
        if ( orientation() == Qt::Vertical )
            d = maxLabelWidth(font);
        else
            d = maxLabelHeight(font);

        if ( d > 0 )
            d += spacing();
    }

    if ( hasComponent(QwtAbstractScaleDraw::Ticks) )
    {
        d += majTickLength();
    }

    if ( hasComponent(QwtAbstractScaleDraw::Backbone) )
    {
        const int pw = qwtMax( 1, pen.width() );  // penwidth can be zero
        d += pw;
    }

    d = qwtMax(d, minimumExtent());
    return d;
}

/*!
    Align and divide an interval

   \param maxNumSteps Max. number of steps
   \param x1 First limit of the interval (In/Out)
   \param x2 Second limit of the interval (In/Out)
   \param stepSize Step size (Out)

   \sa QwtScaleEngine::setAttribute()
*/
void QwtLog10ScaleEngine::autoScale(int maxNumSteps, 
    double &x1, double &x2, double &stepSize) const
{
    if ( x1 > x2 )
        qSwap(x1, x2);

    QwtDoubleInterval interval(x1 / pow(10.0, lowerMargin()), 
        x2 * pow(10.0, upperMargin()) );

    if (interval.maxValue() / interval.minValue() < 10.0)
    {
        // scale width is less than one decade -> build linear scale

        QwtLinearScaleEngine linearScaler;
        linearScaler.setAttributes(attributes());
        linearScaler.setReference(reference());
        linearScaler.setMargins(lowerMargin(), upperMargin());

        linearScaler.autoScale(maxNumSteps, x1, x2, stepSize);
        stepSize = ::log10(stepSize);

        return;
    }

    double logRef = 1.0;
    if (reference() > LOG_MIN / 2)
        logRef = qwtMin(reference(), LOG_MAX / 2);

    if (testAttribute(QwtScaleEngine::Symmetric))
    {
        const double delta = qwtMax(interval.maxValue() / logRef,  
            logRef / interval.minValue());
        interval.setInterval(logRef / delta, logRef * delta);
    }

    if (testAttribute(QwtScaleEngine::IncludeReference))
        interval = interval.extend(logRef);

    interval = interval.limited(LOG_MIN, LOG_MAX);

    if (interval.width() == 0.0)
        interval = buildInterval(interval.minValue());

    stepSize = divideInterval(log10(interval).width(), qwtMax(maxNumSteps, 1));
    if ( stepSize < 1.0 )
        stepSize = 1.0;

    if (!testAttribute(QwtScaleEngine::Floating))
        interval = align(interval, stepSize);

    x1 = interval.minValue();
    x2 = interval.maxValue();

    if (testAttribute(QwtScaleEngine::Inverted))
    {
        qSwap(x1, x2);
        stepSize = -stepSize;
    }
}

int DiMap::limTransform(double x) const
{
	if (x > qwtMax(d_x1, d_x2))
		x = qwtMax(d_x1, d_x2);
	else if (x < qwtMin(d_x1, d_x2))
		x = qwtMin(d_x1, d_x2);
	return transform(x);
}

/*!
    Returns a size with the maximum width and height of this
    size and other.
*/
QwtDoubleSize QwtDoubleSize::expandedTo(
    const QwtDoubleSize &other) const
{
    return QwtDoubleSize(
        qwtMax(d_width, other.d_width),
        qwtMax(d_height, other.d_height)
    );
}

QRect QwtPicker::trackerRect(QPainter *painter) const
{
    if ( trackerMode() == AlwaysOff || 
        (trackerMode() == ActiveOnly && !isActive() ) )
    {
        return QRect();
    }

    if ( d_data->labelPosition.x() < 0 || d_data->labelPosition.y() < 0 )
        return QRect();

    QwtText text = trackerText(d_data->labelPosition);
    if ( text.isEmpty() )
        return QRect();

    QRect textRect(QPoint(0, 0), text.textSize(painter->font()));

    const QPoint &pos = d_data->labelPosition;

    int alignment = 0;
    if ( isActive() && d_data->selection.count() > 1 
        && rubberBand() != NoRubberBand )
    {
        const QPoint last = 
            d_data->selection[int(d_data->selection.count()) - 2];

        alignment |= (pos.x() >= last.x()) ? Qt::AlignRight : Qt::AlignLeft;
        alignment |= (pos.y() > last.y()) ? Qt::AlignBottom : Qt::AlignTop;
    }
    else
        alignment = Qt::AlignTop | Qt::AlignRight;

    const int margin = 5;

    int x = pos.x();
    if ( alignment & Qt::AlignLeft )
        x -= textRect.width() + margin;
    else if ( alignment & Qt::AlignRight )
        x += margin;

    int y = pos.y();
    if ( alignment & Qt::AlignBottom )
        y += margin;
    else if ( alignment & Qt::AlignTop )
        y -= textRect.height() + margin;
    
    textRect.moveTopLeft(QPoint(x, y));

    int right = qwtMin(textRect.right(), pickRect().right() - margin);
    int bottom = qwtMin(textRect.bottom(), pickRect().bottom() - margin);
    textRect.moveBottomRight(QPoint(right, bottom));

    int left = qwtMax(textRect.left(), pickRect().left() + margin);
    int top = qwtMax(textRect.top(), pickRect().top() + margin);
    textRect.moveTopLeft(QPoint(left, top));

    return textRect;
}

/*!
    Align and divide an interval

   \param maxNumSteps Max. number of steps
   \param x1 First limit of the interval (In/Out)
   \param x2 Second limit of the interval (In/Out)
   \param stepSize Step size (Out)

   \sa QwtScaleEngine::setAttribute
*/
void LogTimeScaleEngine::autoScale(int maxNumSteps, 
    double &x1, double &x2, double &stepSize) const
{
    if ( x1 > x2 )
        qSwap(x1, x2);

    QwtDoubleInterval interval(
                               
     #if (QWT_VERSION >= 0x050200)
            x1 / pow(10.0, lowerMargin()), 
            x2 * pow(10.0, upperMargin())
     #else
            x1 / pow(10.0, loMargin()), 
            x2 * pow(10.0, hiMargin())
    #endif
    );

    double logRef = 1.0;
    if (reference() > LOG_MIN / 2)
        logRef = qwtMin(reference(), LOG_MAX / 2);

    if (testAttribute(QwtScaleEngine::Symmetric))
    {
        const double delta = qwtMax(interval.maxValue() / logRef,  
            logRef / interval.minValue());
        interval.setInterval(logRef / delta, logRef * delta);
    }

    if (testAttribute(QwtScaleEngine::IncludeReference))
        interval = interval.extend(logRef);

    interval = interval.limited(LOG_MIN, LOG_MAX);

    if (interval.width() == 0.0)
        interval = buildInterval(interval.minValue());

    stepSize = divideInterval(log10(interval).width(), qwtMax(maxNumSteps, 1));
    if ( stepSize < 1.0 )
        stepSize = 1.0;

    if (!testAttribute(QwtScaleEngine::Floating))
        interval = align(interval, stepSize);

    x1 = interval.minValue();
    x2 = interval.maxValue();

    if (testAttribute(QwtScaleEngine::Inverted))
    {
        qSwap(x1, x2);
        stepSize = -stepSize;
    }
}

/*!
  Move the the current zoom rectangle.

  \param x X value
  \param y Y value

  \sa QwtDoubleRect::move
  \note The changed rectangle is limited by the zoom base
*/
void QwtPlotZoomer::move(double x, double y)
{
    x = qwtMax(x, zoomBase().left());
    x = qwtMin(x, zoomBase().right() - zoomRect().width());

    y = qwtMax(y, zoomBase().top());
    y = qwtMin(y, zoomBase().bottom() - zoomRect().height());

    if ( x != zoomRect().left() || y != zoomRect().top() )
    {
        d_data->zoomStack[d_data->zoomRectIndex].moveTo(x, y);
        rescale();
    }
}

/*!
  Returns the intersection of this rectangle and rectangle other.
  Returns an empty rectangle if there is no intersection.
*/
QwtDoubleRect QwtDoubleRect::operator&(const QwtDoubleRect &other) const
{
    if (isNull() || other.isNull())
        return QwtDoubleRect();

    const QwtDoubleRect r1 = normalized();
    const QwtDoubleRect r2 = other.normalized();

    const double minX = qwtMax(r1.left(), r2.left());
    const double maxX = qwtMin(r1.right(), r2.right());
    const double minY = qwtMax(r1.top(), r2.top());
    const double maxY = qwtMin(r1.bottom(), r2.bottom());

    return QwtDoubleRect(minX, minY, maxX - minX, maxY - minY);
}

/*!
  Returns the bounding rectangle of this rectangle and rectangle other.
  The bounding rectangle of a nonempty rectangle and an empty or
  invalid rectangle is defined to be the nonempty rectangle.
*/
QwtDoubleRect QwtDoubleRect::operator|(const QwtDoubleRect &other) const
{
    if ( isEmpty() )
        return other;

    if ( other.isEmpty() )
        return *this;

    const double minX = qwtMin(d_left, other.d_left);
    const double maxX = qwtMax(d_right, other.d_right);
    const double minY = qwtMin(d_top, other.d_top);
    const double maxY = qwtMax(d_bottom, other.d_bottom);

    return QwtDoubleRect(minX, minY, maxX - minX, maxY - minY);
}

void Knob::drawMarker(QPainter *p, double arc, const QColor &c)
{

	QPen pn;
	int radius;
	double rb, re;
	double rarc;

	rarc = arc * M_PI / 180.0;
	double ca = cos(rarc);
	double sa = -sin(rarc);
	radius = kRect.width() / 2 - d_borderWidth;
	if (radius < 3) radius = 3;
	int ym = kRect.y() + radius + d_borderWidth;
	int xm = kRect.x() + radius + d_borderWidth;

	switch (d_symbol)
	{
		case Dot:

			p->setBrush(c);
			p->setPen(Qt::NoPen);
			rb = double(qwtMax(radius - 4 - d_dotWidth / 2, 0));
			p->drawEllipse(xm - int(rint(sa * rb)) - d_dotWidth / 2,
					ym - int(rint(ca * rb)) - d_dotWidth / 2,
					d_dotWidth, d_dotWidth);

			break;

		case Line:

			pn.setColor(c);
			pn.setWidth(3);
			p->setPen(pn);

			rb = qwtMax(double((radius - 4) / 3.0), 0.0);
			re = qwtMax(double(radius - 4), 0.0);

			p->drawLine(xm - int(rint(sa * rb)),
					ym - int(rint(ca * rb)),
					xm - int(rint(sa * re)),
					ym - int(rint(ca * re)));

			break;
	}


}