const QwtArray<QwtDoublePoint> &points) const
#else
QPolygonF QwtSplineCurveFitter::fitSpline(
const QPolygonF &points) const
#endif
{
d_data->spline.setPoints(points);
if ( !d_data->spline.isValid() )
return points;
#if QT_VERSION < 0x040000
QwtArray<QwtDoublePoint> fittedPoints(d_data->splineSize);
#else
QPolygonF fittedPoints(d_data->splineSize);
#endif
const double x1 = points[0].x();
const double x2 = points[int(points.size() - 1)].x();
const double dx = x2 - x1;
const double delta = dx / (d_data->splineSize - 1);
for (int i = 0; i < d_data->splineSize; i++)
{
QwtDoublePoint &p = fittedPoints[i];
const double v = x1 + i * delta;
const double sv = d_data->spline.value(v);
p.setX(qRound(v));
p.setY(qRound(sv));
}
d_data->spline.reset();
return fittedPoints;
}
QPolygonF QwtSplineCurveFitter::fitSpline( const QPolygonF &points ) const
{
d_data->spline.setPoints( points );
if ( !d_data->spline.isValid() )
return points;
QPolygonF fittedPoints( d_data->splineSize );
const double x1 = points[0].x();
const double x2 = points[int( points.size() - 1 )].x();
const double dx = x2 - x1;
const double delta = dx / ( d_data->splineSize - 1 );
for ( int i = 0; i < d_data->splineSize; i++ )
{
QPointF &p = fittedPoints[i];
const double v = x1 + i * delta;
const double sv = d_data->spline.value( v );
p.setX( qRound( v ) );
p.setY( qRound( sv ) );
}
d_data->spline.reset();
return fittedPoints;
}
QPolygonF QwtSplineCurveFitter::fitParametric( const QPolygonF &points ) const
{
int i;
const int size = points.size();
QPolygonF fittedPoints( d_data->splineSize );
QPolygonF splinePointsX( size );
QPolygonF splinePointsY( size );
const QPointF *p = points.data();
QPointF *spX = splinePointsX.data();
QPointF *spY = splinePointsY.data();
double param = 0.0;
for ( i = 0; i < size; i++ )
{
const double x = p[i].x();
const double y = p[i].y();
if ( i > 0 )
{
const double delta = qSqrt( qwtSqr( x - spX[i-1].y() )
+ qwtSqr( y - spY[i-1].y() ) );
param += qMax( delta, 1.0 );
}
spX[i].setX( param );
spX[i].setY( x );
spY[i].setX( param );
spY[i].setY( y );
}
d_data->spline.setPoints( splinePointsX );
if ( !d_data->spline.isValid() )
return points;
const double deltaX =
splinePointsX[size - 1].x() / ( d_data->splineSize - 1 );
for ( i = 0; i < d_data->splineSize; i++ )
{
const double dtmp = i * deltaX;
fittedPoints[i].setX( qRound( d_data->spline.value( dtmp ) ) );
}
d_data->spline.setPoints( splinePointsY );
if ( !d_data->spline.isValid() )
return points;
const double deltaY =
splinePointsY[size - 1].x() / ( d_data->splineSize - 1 );
for ( i = 0; i < d_data->splineSize; i++ )
{
const double dtmp = i * deltaY;
fittedPoints[i].setY( qRound( d_data->spline.value( dtmp ) ) );
}
return fittedPoints;
}