/**
* Calculate dx, dy values for a point
*
* @param t : parameter
* @param delta : where to store dx, dy values
*/
private void calcTangentAt(double t, FPoint2 delta) {
final boolean db = false;
if (db) {
System.out.println("calcTangentAt " + t);
}
t = toInt(t);
if (db) {
System.out.println(" flipped=" + flipped() + " ti=" + t);
}
double a = toW2.get(0, 0), b = toW2.get(0, 1), c = toW2.get(0, 2);
double d = toW2.get(1, 0), e = toW2.get(1, 1), f = toW2.get(1, 2);
if (db) {
System.out.println(" a=" + a + " b=" + b + " c=" + c + "\n d=" + d + " e=" + e + " f=" + f);
}
double rt = Polyn.sqrt(A + B * t * t);
double dx = a * B * t / rt + b;
double dy = d * B * t / rt + e;
if (flipped()) {
dx = -dx;
dy = -dy;
}
if (db) {
System.out.println(" dx=" + dx + "\n dy=" + dy);
System.out.println(" ratio=" + (dy / dx));
}
delta.setLocation(dx, dy);
}
/**
* Determine where point is relative to arm
*
* @param x :
* @param y : point to test
* @return an integer, which is 0 if it's on the arm, 1 if it's to the right of the arm, -1 if
* it's to the left of the arm
*/
public int testPoint(double x, double y) {
final FPoint2 ept = new FPoint2(), eps = new FPoint2();
eps.setLocation(x, y);
toCurveSpace(eps, ept);
FPoint2 as = calcPointInArmSpace(toExt(ept.y));
int out = 0;
double diff = ept.x - as.x;
if (diff > 0) {
out = 1;
} else if (diff < 0) {
out = -1;
}
if (flipped()) {
out = -out;
}
return out;
}
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();
}
}
}