RCircle RCircle::createFrom3Points(const RVector& p1,
const RVector& p2,
const RVector& p3) {
// intersection of two middle lines
// middle points between first two points:
RVector mp1 = RVector::getAverage(p1, p2);
double a1 = p1.getAngleTo(p2) + M_PI / 2.0;
// direction from middle point to center:
RVector dir1 = RVector::createPolar(1.0, a1);
// middle points between last two points:
RVector mp2 = RVector::getAverage(p2, p3);
double a2 = p2.getAngleTo(p3) + M_PI / 2.0;
// direction from middle point to center:
RVector dir2 = RVector::createPolar(1.0, a2);
RLine midLine1(mp1, mp1 + dir1);
RLine midLine2(mp2, mp2 + dir2);
QList<RVector> ips = midLine1.getIntersectionPoints(midLine2, false);
if (ips.length()!=1) {
return RCircle();
}
RVector center = ips[0];
double radius = center.getDistanceTo(p3);
// double angle1 = center.getAngleTo(p1);
// double angle2 = center.getAngleTo(p3);
// bool reversed = RMath::isAngleBetween(center.getAngleTo(p2),
// angle1, angle2, true);
return RCircle(center, radius);
}
QList<RVector> RShape::getIntersectionPointsAE(const RArc& arc1,
const REllipse& ellipse2, bool limited) {
QList<RVector> candidates =
RShape::getIntersectionPointsCE(
RCircle(arc1.getCenter(), arc1.getRadius()),
ellipse2);
if (!limited) {
return candidates;
}
QList<RVector> res;
for (int i=0; i<candidates.count(); i++) {
RVector c = candidates[i];
if (arc1.isOnShape(c)) {
if (!ellipse2.isFullEllipse()) {
double a1 = ellipse2.getCenter().getAngleTo(ellipse2.getStartPoint());
double a2 = ellipse2.getCenter().getAngleTo(ellipse2.getEndPoint());
double a = ellipse2.getCenter().getAngleTo(c);
if (!RMath::isAngleBetween(a, a1, a2, ellipse2.isReversed())) {
continue;
}
}
res.append(c);
}
}
return res;
}
QList<RVector> RShape::getIntersectionPointsAA(const RArc& arc1,
const RArc& arc2, bool limited) {
QList<RVector> candidates =
RShape::getIntersectionPoints(
RCircle(arc1.getCenter(), arc1.getRadius()),
RCircle(arc2.getCenter(), arc2.getRadius())
);
if (!limited) {
return candidates;
}
QList<RVector> res;
for (int i=0; i<candidates.count(); i++) {
if (arc1.isOnShape(candidates[i]) && arc2.isOnShape(candidates[i])) {
res.append(candidates[i]);
}
}
// ret.setTangent(tangent);
return res;
}
RCircle RCircle::createFrom2Points(const RVector& p1, const RVector& p2) {
RVector center = (p1+p2)/2.0;
double radius = p1.getDistanceTo(p2)/2.0;
return RCircle(center, radius);
}
