示例#1
0
  /**
   * 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;
  }
示例#2
0
  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();
      }
    }
  }