void REllipseEntity::print(QDebug dbg) const {
dbg.nospace() << "REllipseEntity(";
REntity::print(dbg);
dbg.nospace() << ", center: " << getCenter();
dbg.nospace() << ", majorPoint: " << getMajorPoint();
dbg.nospace() << ", ratio: " << getRatio();
dbg.nospace() << ", startAngle: " << getStartAngle();
dbg.nospace() << ", endAngle: " << getEndAngle();
dbg.nospace() << ", reversed: " << isReversed() << ")";
}
bool REllipse::switchMajorMinor() {
if (fabs(ratio) < RS::PointTolerance) {
return false;
}
RVector vp_start=getStartPoint();
RVector vp_end=getStartPoint();
RVector vp=getMajorPoint();
setMajorPoint(RVector(-ratio*vp.y, ratio*vp.x));
setRatio(1.0/ratio);
setStartParam(getParamTo(vp_start));
setEndParam(getParamTo(vp_end));
return true;
}
void REllipse::print(QDebug dbg) const {
dbg.nospace() << "REllipse(";
RShape::print(dbg);
dbg.nospace() << ", startPoint: " << getStartPoint()
<< ", endPoint: " << getEndPoint()
<< ", center: " << getCenter()
<< ", majorPoint: " << getMajorPoint()
<< ", majorRadius: " << getMajorRadius()
<< ", minorRadius: " << getMinorRadius()
<< ", ratio: " << getRatio()
<< ", startAngle: " << RMath::rad2deg(getStartParam())
<< ", endAngle: " << RMath::rad2deg(getEndParam())
<< ", full: " << isFullEllipse()
<< ", clockwise: " << isReversed()
<< ")";
}
QSharedPointer<RShape> REllipse::getTransformed(const QTransform& transform) const {
RVector ct = center.getTransformed2d(transform);
RVector mp = center + getMajorPoint();
RVector mpt = mp.getTransformed2d(transform);
RVector sp = getStartPoint();
RVector spt = sp.getTransformed2d(transform);
RVector ep = getEndPoint();
RVector ept = ep.getTransformed2d(transform);
QSharedPointer<REllipse> ret = QSharedPointer<REllipse>(
new REllipse(
ct,
mpt - ct,
ratio,
0.0,
M_PI*2,
reversed
)
);
ret->setStartParam(ret->getParamTo(spt));
ret->setEndParam(ret->getParamTo(ept));
return ret;
}
QList<RLine> REllipse::getTangents(const RVector& point) const {
QList<RLine> ret;
if (getDistanceTo(point, false) < RS::PointTolerance) {
// point is on ellipse:
return ret;
}
// point is at center (prevents recursion when swapping ellipse minor / major):
if (point.getDistanceTo(getCenter())<RS::PointTolerance) {
return ret;
}
// swap ellipse minor / major if point is on minor axis
// 20120928: and not also on major axis (prevent recursion):
RLine minorAxis(getCenter(), getCenter() + getMinorPoint());
RLine majorAxis(getCenter(), getCenter() + getMajorPoint());
if (minorAxis.isOnShape(point, false) && !majorAxis.isOnShape(point, false)) {
REllipse e2 =*this;
e2.majorPoint = getMinorPoint();
e2.ratio = 1.0/ratio;
return e2.getTangents(point);
}
double a = getMajorRadius(); // the length of the major axis / 2
double b = getMinorRadius(); // the length of the minor axis / 2
// rotate and move point:
RVector point2 = point;
point2.move(-getCenter());
point2.rotate(-getAngle());
double xp = point2.x; // coordinates of the given point
double yp = point2.y;
double xt1; // Tangent point 1
double yt1;
double xt2; // Tangent point 2
double yt2;
double a2 = a * a;
double b2 = b * b;
double d = a2 / b2 * yp / xp;
double e = a2 / xp;
double af = b2 * d * d + a2;
double bf = -b2 * d * e * 2.0;
double cf = b2 * e * e - a2 * b2;
double t = sqrt(bf * bf - af * cf * 4.0);
if (RMath::isNaN(t)) {
return ret;
}
yt1 = (t - bf) / (af * 2.0);
xt1 = e - d * yt1;
yt2 = (-t - bf) / (af * 2.0);
xt2 = e - d * yt2;
RVector s1(xt1, yt1);
s1.rotate(getAngle());
s1.move(getCenter());
RVector s2(xt2, yt2);
s2.rotate(getAngle());
s2.move(getCenter());
if (s1.isValid()) {
ret.append(RLine(point, s1));
}
if (s2.isValid()) {
ret.append(RLine(point, s2));
}
return ret;
}
QList<RVector> REllipse::getFoci() const {
RVector vp(getMajorPoint() * sqrt(1.0 - getRatio()*getRatio()));
return QList<RVector>() << getCenter()+vp << getCenter()-vp;
}
