/**
* Determine closest point on hyperbolic arm to a point pt
*
* @param pt : point
* @return t value for closest point; not necessarily within clipped range
*/
public double closestPointTo(FPoint2 pt) {
final boolean db = false;
pt = toCurveSpace(pt, null);
double U = B + 1;
double V = -pt.y;
double W = B * pt.x;
Polyn p =
new Polyn( //
B * U * U, //
2 * B * U * V, //
B * V * V + A * U * U - W * W, //
2 * A * U * V, //
A * V * V //
);
if (db) Streams.out.println("closestPointTo, pt=" + pt + "\n" + p);
double ret = 0;
try {
DArray r = new DArray();
if (Math.abs(p.c(0)) < 1e-5) r.addDouble(0);
else p.solve(r);
if (r.isEmpty()) {
throw new FPError("can't find closest point, poly=\n" + p);
}
double bestDist = 0;
for (int i = 0; i < r.size(); i++) {
double t = r.getDouble(i);
FPoint2 apt = calcPoint(t);
double dist = apt.distance(pt);
if (i == 0 || dist < bestDist) {
bestDist = dist;
ret = t;
}
}
} catch (FPError e) {
Tools.warn("caught FPError");
// Streams.out.println("caught:\n" + e);
ret = (this.minParameter() + this.maxParameter()) * .5;
}
return ret;
}
public void render(Color c, int stroke, int markType) {
final boolean db = false;
// Get array of visible segments. If no such array exists,
// use default.
DArray vseg = visSeg;
boolean dashed = false;
// if (step == 0) {
double step = renderStep();
// }
// vp V = TestBed.view();
if (db) Streams.out.println(" step=" + step);
// plot each visible segment
for (int seg = 0; seg < vseg.size(); seg += 2) {
double t0 = vseg.getDouble(seg + 0), t1 = vseg.getDouble(seg + 1);
t0 = MyMath.clamp(t0, -500.0, 500.0);
t1 = MyMath.clamp(t1, -500.0, 500.0);
// render() expects external parameters.
double s0 = toExt(t0), s1 = toExt(t1);
if (s0 > s1) {
double tmp = s0;
s0 = s1;
s1 = tmp;
}
FPoint2 p0 = calcPoint(s0), p1 = calcPoint(s1);
if (db) Streams.out.println(" p0=" + p0 + ", p1=" + p1);
if (isLine() && !dashed) {
V.drawLine(p0, p1);
} else {
/*
if (Math.abs(s0) >= 500
||Math.abs(s1) >= 500)
System.out.println("Rendering "+t0+" to "+t1+" step "+step);
*/
if (dashed) V.pushStroke(Globals.STRK_RUBBERBAND);
{
// int count = 0;
boolean first = true;
for (double t = t0; ; t += step) { // , count++) {
boolean last = (t >= t1);
if (last) {
t = t1;
}
calcPointInternal(t, p1);
if (!p1.isValid()) {
if (last) {
break;
}
continue;
}
if (db) {
System.out.println(" calcPt " + Tools.f(toExt(t)) + " = " + p1.x + "," + p1.y);
}
if (!first) {
V.drawLine(p0, p1);
if (false) {
Tools.warn("highlighting int");
V.mark(p0);
}
}
if (last) {
break;
}
p0.setLocation(p1);
first = false;
}
}
if (dashed) V.popStroke();
}
}
}
