Curve* EllipticalArc::portion(double f, double t) const
{
// fix input arguments
if (f < 0) f = 0;
if (f > 1) f = 1;
if (t < 0) t = 0;
if (t > 1) t = 1;
if ( are_near(f, t) )
{
EllipticalArc *arc = static_cast<EllipticalArc*>(duplicate());
arc->_center = arc->_initial_point = arc->_final_point = pointAt(f);
arc->_start_angle = arc->_end_angle = _start_angle;
arc->_rot_angle = _rot_angle;
arc->_sweep = _sweep;
arc->_large_arc = _large_arc;
return arc;
}
EllipticalArc *arc = static_cast<EllipticalArc*>(duplicate());
arc->_initial_point = pointAt(f);
arc->_final_point = pointAt(t);
if ( f > t ) arc->_sweep = !_sweep;
if ( _large_arc && fabs(sweepAngle() * (t-f)) < M_PI)
arc->_large_arc = false;
arc->_updateCenterAndAngles(arc->isSVGCompliant()); //TODO: be more clever
return arc;
}
double QgsGeometryUtils::circleLength( double x1, double y1, double x2, double y2, double x3, double y3 )
{
double centerX, centerY, radius;
circleCenterRadius( QgsPointV2( x1, y1 ), QgsPointV2( x2, y2 ), QgsPointV2( x3, y3 ), radius, centerX, centerY );
double length = M_PI / 180.0 * radius * sweepAngle( centerX, centerY, x1, y1, x2, y2, x3, y3 );
if ( length < 0 )
{
length = -length;
}
return length;
}
void SpiralShape::updatePath(const QSizeF &size)
{
createPath(size);
normalize();
#if 0
Q_UNUSED(size);
QPointF startpoint(m_handles[0]);
QPointF curvePoints[12];
int pointCnt = arcToCurve(m_radii.x(), m_radii.y(), m_startAngle, sweepAngle() , startpoint, curvePoints);
int cp = 0;
m_points[cp]->setPoint(startpoint);
m_points[cp]->unsetProperty(KoPathPoint::HasControlPoint1);
for (int i = 0; i < pointCnt; i += 3)
{
m_points[cp]->setControlPoint2(curvePoints[i]);
m_points[++cp]->setControlPoint1(curvePoints[i+1]);
m_points[cp]->setPoint(curvePoints[i+2]);
m_points[cp]->unsetProperty(KoPathPoint::HasControlPoint2);
}
if (m_type == Curve)
{
m_points[++cp]->setPoint(m_center);
m_points[cp]->unsetProperty(KoPathPoint::HasControlPoint1);
m_points[cp]->unsetProperty(KoPathPoint::HasControlPoint2);
}
else if (m_type == Line && m_startAngle == m_endAngle)
{
m_points[0]->setControlPoint1(m_points[cp]->controlPoint1());
m_points[0]->setPoint(m_points[cp]->point());
--cp;
}
m_subpaths[0]->clear();
for (int i = 0; i <= cp; ++i)
{
if (i < cp || (m_type == Line && m_startAngle != m_endAngle))
{
m_points[i]->unsetProperty(KoPathPoint::CloseSubpath);
}
else
{
m_points[i]->setProperty(KoPathPoint::CloseSubpath);
}
m_subpaths[0]->push_back(m_points[i]);
}
#endif
}
D2<SBasis> EllipticalArc::toSBasis() const
{
D2<SBasis> arc;
// the interval of parametrization has to be [0,1]
Coord et = initialAngle().radians() + ( _sweep ? sweepAngle() : -sweepAngle() );
Linear param(initialAngle(), et);
Coord cos_rot_angle, sin_rot_angle;
sincos(_rot_angle, sin_rot_angle, cos_rot_angle);
// order = 4 seems to be enough to get a perfect looking elliptical arc
SBasis arc_x = ray(X) * cos(param,4);
SBasis arc_y = ray(Y) * sin(param,4);
arc[0] = arc_x * cos_rot_angle - arc_y * sin_rot_angle + Linear(center(X),center(X));
arc[1] = arc_x * sin_rot_angle + arc_y * cos_rot_angle + Linear(center(Y),center(Y));
// ensure that endpoints remain exact
for ( int d = 0 ; d < 2 ; d++ ) {
arc[d][0][0] = initialPoint()[d];
arc[d][0][1] = finalPoint()[d];
}
return arc;
}
