/*!
\brief Determine the value corresponding to a specified position
Called by QwtAbstractSlider
\param pos point
*/
double QwtKnob::getValue( const QPoint &pos )
{
const double dx = rect().center().x() - pos.x();
const double dy = rect().center().y() - pos.y();
const double arc = qAtan2( -dx, dy ) * 180.0 / M_PI;
double newValue = 0.5 * ( minValue() + maxValue() )
+ ( arc + d_data->nTurns * 360.0 ) * ( maxValue() - minValue() )
/ d_data->totalAngle;
const double oneTurn = qFabs( maxValue() - minValue() ) * 360.0 / d_data->totalAngle;
const double eqValue = value() + mouseOffset();
if ( qFabs( newValue - eqValue ) > 0.5 * oneTurn )
{
if ( newValue < eqValue )
newValue += oneTurn;
else
newValue -= oneTurn;
}
return newValue;
}
/*!
\brief Determine the value corresponding to a specified position
Called by QwtAbstractSlider
\param p point
*/
double QwtKnob::getValue(const QPoint &p)
{
const double dx = double((rect().x() + rect().width() / 2) - p.x() );
const double dy = double((rect().y() + rect().height() / 2) - p.y() );
const double arc = atan2(-dx,dy) * 180.0 / M_PI;
double newValue = 0.5 * (minValue() + maxValue())
+ (arc + d_data->nTurns * 360.0) * (maxValue() - minValue())
/ d_data->totalAngle;
const double oneTurn = fabs(maxValue() - minValue()) * 360.0 / d_data->totalAngle;
const double eqValue = value() + mouseOffset();
if (fabs(newValue - eqValue) > 0.5 * oneTurn)
{
if (newValue < eqValue)
newValue += oneTurn;
else
newValue -= oneTurn;
}
return newValue;
}
/*!
Find the value for a given position
\param pos Position
\return Value
*/
double QwtDial::getValue( const QPoint &pos )
{
if ( d_data->maxScaleArc == d_data->minScaleArc || maxValue() == minValue() )
return minValue();
double dir = line2Radians( innerRect().center(), pos ) - d_data->origin;
if ( dir < 0.0 )
dir += 360.0;
if ( mode() == RotateScale )
dir = 360.0 - dir;
// The position might be in the area that is outside the scale arc.
// We need the range of the scale if it was a complete circle.
const double completeCircle = 360.0 / ( d_data->maxScaleArc - d_data->minScaleArc )
* ( maxValue() - minValue() );
double posValue = minValue() + completeCircle * dir / 360.0;
if ( scrollMode() == ScrMouse )
{
if ( d_data->previousDir >= 0.0 ) // valid direction
{
// We have to find out whether the mouse is moving
// clock or counter clockwise
bool clockWise = false;
const double angle = dir - d_data->previousDir;
if ( ( angle >= 0.0 && angle <= 180.0 ) || angle < -180.0 )
clockWise = true;
if ( clockWise )
{
if ( dir < d_data->previousDir && mouseOffset() > 0.0 )
{
// We passed 360 -> 0
setMouseOffset( mouseOffset() - completeCircle );
}
if ( wrapping() )
{
if ( posValue - mouseOffset() > maxValue() )
{
// We passed maxValue and the value will be set
// to minValue. We have to adjust the mouseOffset.
setMouseOffset( posValue - minValue() );
}
}
else
{
if ( posValue - mouseOffset() > maxValue() ||
value() == maxValue() )
{
// We fix the value at maxValue by adjusting
// the mouse offset.
setMouseOffset( posValue - maxValue() );
}
}
}
else
{
if ( dir > d_data->previousDir && mouseOffset() < 0.0 )
{
// We passed 0 -> 360
setMouseOffset( mouseOffset() + completeCircle );
}
if ( wrapping() )
{
if ( posValue - mouseOffset() < minValue() )
{
// We passed minValue and the value will be set
// to maxValue. We have to adjust the mouseOffset.
setMouseOffset( posValue - maxValue() );
}
}
else
{
if ( posValue - mouseOffset() < minValue() ||
value() == minValue() )
{
// We fix the value at minValue by adjusting
// the mouse offset.
setMouseOffset( posValue - minValue() );
}
}
}
}
d_data->previousDir = dir;
}
return posValue;
}
