1 package edu.berkeley.qfat;
4 import java.awt.event.*;
6 import javax.media.opengl.*;
7 import javax.media.opengl.glu.*;
8 import edu.berkeley.qfat.geom.*;
9 import edu.wlu.cs.levy.CG.KDTree;
10 import edu.berkeley.qfat.bind.*;
11 import edu.berkeley.qfat.geom.Point;
12 import com.infomatiq.jsi.IntProcedure;
14 // EDGES RUN COUNTER-CLOCKWISE
16 public class Mesh implements Iterable<Mesh.T> {
18 public static final float EPSILON = (float)0.0001;
19 public static final Random random = new Random();
21 private RTree<T> triangles = new RTree<T>();
22 private PointSet<Vertex> vertices = new PointSet<Vertex>();
24 public boolean option_wireframe = false;
25 public boolean option_errorNormals = false;
26 public boolean option_selectable = true;
28 public void render(GL gl, Matrix m) {
29 if (option_wireframe) {
30 gl.glDisable(GL.GL_LIGHTING);
31 gl.glBegin(GL.GL_LINES);
32 gl.glColor3f(1, 1, 1);
34 // fixme used to be .goodp
35 m.times(t.e1().v1.p).glVertex(gl);
36 m.times(t.e1().v2.p).glVertex(gl);
37 m.times(t.e2().v1.p).glVertex(gl);
38 m.times(t.e2().v2.p).glVertex(gl);
39 m.times(t.e3().v1.p).glVertex(gl);
40 m.times(t.e3().v2.p).glVertex(gl);
43 gl.glEnable(GL.GL_LIGHTING);
47 gl.glColor4f((float)(0.25+(0.05*t.color)),
48 (float)(0.25+(0.05*t.color)),
49 (float)(0.75+(0.05*t.color)),
53 gl.glColor4f((float)(0.75+(0.05*t.color)),
54 (float)(0.25+(0.05*t.color)),
55 (float)(0.25+(0.05*t.color)),
61 if (option_errorNormals)
63 for(Mesh.Vertex p : new Mesh.Vertex[] { t.v1(), t.v2(), t.v3() }) {
65 gl.glBegin(GL.GL_LINES);
66 gl.glColor3f(1, 1, 1);
68 p.p.plus(p.norm().times((float)p.error()*10)).glVertex(gl);
74 public boolean immutableVertices;
75 public Mesh error_against = null;
76 public double error = 0;
78 public Mesh(boolean immutableVertices) { this.immutableVertices = immutableVertices; }
80 public void makeVerticesImmutable() { this.immutableVertices = true; }
81 public float error() { return (float)error; }
83 public int size() { return vertices.size(); }
84 public Iterable<Vertex> vertices() { return vertices; }
85 public Iterator<T> iterator() { return triangles.iterator(); }
87 public void rebindPoints() {
89 for(Mesh.T t : this) {
94 // ask edges to re-implement their bindings
95 for(Mesh.T t : this) {
100 System.out.println("rebound!");
103 public void transform(Matrix m) {
104 ArrayList<Vertex> set = new ArrayList<Vertex>();
105 for(Vertex v : vertices) set.add(v);
106 for(Vertex v : set) v.transform(m.times(v.p), true, null);
107 for(Vertex v : set) v.goodp = v.p;
110 public void rebuild() { /*vertices.rebuild();*/ }
111 public Vec diagonal() { return vertices.diagonal(); }
112 public Point centroid() { return vertices.centroid(); }
113 public Vertex nearest(Point p) { return vertices.nearest(p); }
115 /** compute the volume of the mesh */
116 public float volume() {
119 double area = t.area();
120 Vec origin_to_centroid = new Vec(new Point(0, 0, 0), t.centroid());
121 boolean facingAway = t.norm().dot(origin_to_centroid) > 0;
122 double height = Math.abs(t.norm().dot(origin_to_centroid));
123 total += ((facingAway ? 1 : -1) * area * height) / 3.0;
129 public void subdivide() {
130 for (Vertex v : vertices()) v.original = true;
131 HashSet<E> edges = new HashSet<E>();
132 HashSet<E> flip = new HashSet<E>();
133 HashSet<T> tris = new HashSet<T>();
142 System.out.println("triangles="+count);
145 if (e.destroyed || e.shattered) continue;
146 e.shatter().edge = true;
147 for(E ex : (Iterable<E>)e.getBoundPeers()) {
148 Vertex m = nearest(ex.midpoint());
150 E e3 = ex.v1.getE(m).next;
160 System.out.println("flip!");
164 System.out.println("count="+count);
167 HashSet<Vertex> verts = new HashSet<Vertex>();
168 for(Vertex v : vertices()) verts.add(v);
169 for (Vertex v : verts)
171 for (Vertex v : verts) {
173 for(E e = v.e; e!=null; e=e.pair.next==v.e?null:e.pair.next) {
181 for(E e = v.e; e!=null; e=e.pair.next==v.e?null:e.pair.next) {
182 for(E e2 = e.v2.e; e2!=null; e2=e2.pair.next==e.v2.e?null:e2.pair.next) {
183 if (e2.v2.original) {
190 for (Vertex v : verts)
192 System.out.println("-------------------------------------------------------------------");
194 for (Vertex v : verts) {
197 for(E e = v.e; e!=null; e=e.pair.next==v.e?null:e.pair.next) {
199 v.wish(e.midpoint());
200 v.wish(e.midpoint());
201 v.wish(e.next.pair.t.centroid());
205 for(int j=0; j<n-3; j++)
206 v.wish(v.getPoint());
209 for (Vertex v : verts)
211 for (Vertex v : verts)
216 // Vertexices //////////////////////////////////////////////////////////////////////////////
218 /** a vertex in the mesh */
219 public final class Vertex extends HasQuadric implements Visitor {
220 public Point p, goodp;
222 E e; // some edge *leaving* this point
224 public boolean original = false;
225 public boolean edge = false;
226 public boolean face = false;
228 private int wishes = 0;
229 private Point wish = Point.ZERO;
230 public void clearWish() { wishes = 0; wish = Point.ZERO; }
231 public void wish(HasPoint hp) {
232 Point p = hp.getPoint();
234 wish = new Point(wish.x+p.x, wish.y+p.y, wish.z+p.z);
236 public void grantWish() {
237 for(Vertex v : (Iterable<Vertex>)getBoundPeers()) {
238 if (v==this) continue;
239 if (v.wishes==0) continue;
240 Point p = this.getBindingMatrix(v).times(v.wish.minus(Point.ZERO).div(v.wishes).plus(Point.ZERO));
241 wish = p.minus(Point.ZERO).times(v.wishes).plus(wish);
245 if (wishes==0) return;
246 Vec d = wish.minus(Point.ZERO).div(wishes).plus(Point.ZERO).minus(getPoint());
250 public void avgWish() {
251 if (wishes==0) return;
252 wish = wish.minus(Point.ZERO).div(wishes).plus(Point.ZERO);
256 private boolean illegal = false;
258 public boolean visible = false;
260 public Point getPoint() { return p; }
261 public float error() { return olderror; }
263 private Vertex(Point p) {
267 if (vertices.get(p) != null) throw new Error();
271 public void reinsert() {
272 vertices.remove(this);
274 for(E e = this.e; e!=null; e=e.pair.next==this.e?null:e.pair.next) e.t.reinsert();
277 // the average of all adjacent points
278 public Point recenter() {
281 for(E e = this.e; e!=null; e=e.pair.next==this.e?null:e.pair.next) {
282 vec = vec.plus(e.getOther(this).getPoint().minus(Point.ZERO));
285 return Point.ZERO.plus(vec.div(count));
288 public float olderror = 0;
289 public void setError(float nerror) {
296 public Vertex hack(GL gl, Point mouse) {
297 double dist = Double.MAX_VALUE;
299 for(E e = this.e; e!=null; e=e.pair.next==this.e?null:e.pair.next) {
300 Vertex v = e.getOther(this);
301 double dist2 = v.getPoint().glProject(gl).distance(mouse);
302 if ((cur==null || dist2 < dist) && v.visible) {
311 public float averageTriangleArea() {
314 for(E e = this.e; e!=null; e=e.pair.next==this.e?null:e.pair.next) {
320 public float averageEdgeLength() {
323 for(E e = this.e; e!=null; e=e.pair.next==this.e?null:e.pair.next) {
330 public Matrix _recomputeFundamentalQuadric() {
331 Matrix m = Matrix.ZERO;
333 for(E e = this.e; e!=null; e=e.pair.next==this.e?null:e.pair.next) {
334 m = m.plus(e.t.norm().fundamentalQuadric(e.t.centroid()));
338 m = m.plus(norm().fundamentalQuadric(this.p).times(count));
341 return m.times(1/(float)count);
344 public HasQuadric nearest() { return error_against==null ? null : error_against.vertices.nearest(p, this); }
345 public void computeError() {
346 if (error_against==null) return;
347 if (nearest_in_other_mesh == null && nearest()==null) return;
349 nearest_in_other_mesh != null
350 ? nearest_in_other_mesh.fundamentalQuadric().preAndPostMultiply(p)
351 : nearest().fundamentalQuadric().preAndPostMultiply(p);
352 if (quadric_count != 0)
353 nerror = (nerror + quadric.preAndPostMultiply(p))/(quadric_count+1);
355 if (!immutableVertices && quadric_count == 0) {
356 //nerror = Math.max(nerror, 0.4f);
359 //System.out.println(nerror);
360 for(E e = this.e; e!=null; e=e.pair.next==this.e?null:e.pair.next) {
361 double ang = e.dihedralAngle();
362 if (ang > Math.PI) throw new Error();
363 if (ang < -Math.PI) throw new Error();
364 float minangle = (float)(Math.PI * 0.8);
365 //nerror += ((ang / Math.PI)*(ang/Math.PI)) * e.length() * 0.05;
367 //nerror += (1-e.t.quality())*0.0001;
368 if (ang > minangle) nerror += (ang - minangle);
370 //System.out.println(((ang / Math.PI)*(ang/Math.PI)) * 0.000001);
372 if (e.t.aspect() < 0.2) {
373 nerror += (0.2-e.t.aspect()) * 10;
377 if (!immutableVertices) {
378 Vertex n = (Vertex)nearest();
379 float d = norm().dot(n.norm());
380 if (d > 1 || d < -1) throw new Error();
382 nerror *= (2.0f - d);
384 nerror += 0.0003 * (2.0f + d);
385 nerror *= (2.0f + d);
392 public boolean move(Vec vv, boolean ignoreProblems) {
397 // t2' = t2.getMatrix(t1) * t1'
398 // t2' = t2.getMatrix(t1) * M * t1
399 // t1 = t1.getMatrix(t2) * t2
400 // M * t1 = M * t1.getMatrix(t2) * t2
403 if (bindingGroup!=null && this != bindingGroup.getMaster()) {
404 Matrix m2 = getBindingMatrix(bindingGroup.getMaster());
405 Vec v2 = m2.times(vv.plus(getPoint())).minus(m2.times(getPoint()));
406 return ((Vertex)bindingGroup.getMaster()).move(v2, ignoreProblems);
411 Point pt = vv.plus(getPoint());
413 pt = getBindingConstraint().getProjection(pp);
414 if (pt==null) return false;
415 System.out.println(pt.minus(pp).mag() + " " + getBindingConstraint());
417 for(Vertex v : (Iterable<Vertex>)getBoundPeers()) {
418 Point pt2 = v.getBindingMatrix(this).times(pt);
420 if (Math.abs( v.p.minus(pt2).mag() / pt.minus(op).mag() ) > 5)
421 throw new Error(v.p+" "+pt2+"\n"+op+" "+pt+"\n"+v.getBindingMatrix(this));
422 if (Math.abs( v.p.minus(pt2).mag() / pt.minus(op).mag() ) < 1/5) throw new Error();
424 good &= v.transform(pt2, ignoreProblems, v.getBindingMatrix(this));
427 if (!good && !ignoreProblems) {
428 for(Vertex v : (Iterable<Vertex>)getBoundPeers())
429 v.transform(v.oldp, true, null);
432 for(Vertex v : (Iterable<Vertex>)getBoundPeers())
433 v.recomputeFundamentalQuadricIfNeighborChanged();
434 for(Vertex v : (Iterable<Vertex>)getBoundPeers())
435 v.reComputeErrorAround();
439 public boolean ok = true;
441 /** does NOT update bound pairs! */
442 private boolean transform(Point newp, boolean ignoreProblems, Matrix yes) {
444 if (immutableVertices) throw new Error();
446 unApplyQuadricToNeighbor();
448 boolean illegalbefore = illegal;
451 if (this.p.minus(newp).mag() > 0.1 && !ignoreProblems) {
453 throw new Exception(""+this.p.minus(newp).mag()+" "+ignoreProblems+" "+yes);
454 } catch(Exception e) {
463 applyQuadricToNeighbor();
465 if (!ignoreProblems) {
468 for(E e = this.e; e!=null; e=e.pair.next==this.e?null:e.pair.next)
469 e.v2.quadricStale = true;
470 return !illegal || (illegalbefore && illegal);
473 public void checkLegality() {
475 for(E e = this.e; e!=null; e=e.pair.next==this.e?null:e.pair.next) {
476 if (Math.abs(e.dihedralAngle()) > (Math.PI * 0.9) ||
477 Math.abs(e.next.dihedralAngle()) > (Math.PI * 0.9)) illegal = true;
478 if (e.t.aspect() < 0.2) illegal = true;
481 if (!illegal) triangles.range(oldp, this.p, (Visitor<T>)this);
484 public void reComputeErrorAround() {
486 if (nearest_in_other_mesh != null)
487 nearest_in_other_mesh.reComputeError();
488 for(E e = this.e; e!=null; e=e.pair.next==this.e?null:e.pair.next)
489 e.v2.reComputeError();
492 public boolean visit(Object o) {
493 if (o instanceof Vertex)
494 return ((Vertex)o).e != null && ((Vertex)o).norm().dot(Vertex.this.norm()) >= 0;
496 if (illegal) return false;
497 for(E e = Vertex.this.e; e!=null; e=e.pair.next==Vertex.this.e?null:e.pair.next) {
498 if (!t.has(e.v1) && !t.has(e.v2) && e.intersects(t)) { illegal = true; }
500 if (!e.t.has(t.e1().v1) && !e.t.has(t.e1().v2) && t.e1().intersects(e.t)) { illegal = true; }
501 if (!e.t.has(t.e2().v1) && !e.t.has(t.e2().v2) && t.e2().intersects(e.t)) { illegal = true; }
502 if (!e.t.has(t.e3().v1) && !e.t.has(t.e3().v2) && t.e3().intersects(e.t)) { illegal = true; }
508 public E getEdge() { return e; }
509 public E getFreeIncident() {
510 E ret = getFreeIncident(e, e);
511 if (ret != null) return ret;
512 for(E e = this.e; e!=null; e=e.pair.next==this.e?null:e.pair.next)
513 System.out.println(e + " " + e.t);
514 throw new Error("unable to find free incident to " + this);
517 public E getFreeIncident(E start, E before) {
518 for(E e = start; e!=null; e=e.pair.next==before?null:e.pair.next)
519 if (e.pair.v2 == this && e.pair.t == null && e.pair.next.t == null)
524 public E getE(Point v2) {
525 Vertex v = vertices.get(v2);
526 if (v==null) return null;
529 public E getE(Vertex v2) {
530 if (this.e!=null && this!=this.e.v1 && this!=this.e.v2) throw new RuntimeException();
532 for(E e = this.e; e!=null; e=e.pair.next==this.e?null:e.pair.next) {
533 if (e.v1 == this && e.v2 == v2) return e;
536 if (e.destroyed) throw new RuntimeException("fark " + i + " " + e.prev + " " + (e.prev.next==e) + " " + e.prev.destroyed);
541 private void glNormal(GL gl) {
543 gl.glNormal3f(norm.x, norm.y, norm.z);
546 Vec norm = new Vec(0, 0, 0);
547 for(E e = this.e; e!=null; e=e.pair.next==this.e?null:e.pair.next)
549 norm = norm.plus(e.t.norm().times((float)e.prev.angle()));
553 public void bindTo(Vertex p) { bindTo(Matrix.ONE, p); }
557 /** [UNIQUE] an edge */
558 public final class E extends HasBindingGroup implements Comparable<E> {
560 public void sanity() {
561 if (destroyed) return;
562 if (pair!=null && (pair.v1!=v2 || pair.v2!=v1)) throw new RuntimeException();
563 if (next!=null && next.v1!=v2) throw new RuntimeException();
564 if (prev!=null && prev.v2!=v1) throw new RuntimeException();
567 public final Vertex v1, v2;
568 T t; // triangle to our "left"
569 E prev; // previous half-edge
570 E next; // next half-edge
571 E pair; // partner half-edge
572 boolean shattered = false;
574 public boolean intersects(T t) { return t.intersects(v1.p, v2.p); }
576 public Segment getSegment() { return new Segment(v1.getPoint(), v2.getPoint()); }
579 // FIXME: coplanarity check needed
580 if (destroyed) return;
581 for (E e : (Iterable<E>)getBoundPeers()) {
582 if (!e.pair.isBoundTo(pair)) throw new RuntimeException("cannot flip!");
584 Vertex v1 = t.getOtherVertex(this);
585 Vertex v2 = pair.t.getOtherVertex(pair);
588 T t1 = newT(v1, v2, this.v2);
589 T t2 = newT(v2, v1, this.v1);
597 for (E e : (Iterable<E>)getBoundPeers()) {
598 if (e==this) continue;
599 if (e.destroyed) continue;
600 Vertex v1e = e.t.getOtherVertex(e);
601 Vertex v2e = e.pair.t.getOtherVertex(e.pair);
604 if (v1e.getE(v2e)!=null) throw new RuntimeException();
605 newT(v1e, v2e, e.v2).red = true;
606 newT(v2e, v1e, e.v1).red = true;
607 v2e.getE(v1e).bindTo(e.getBindingMatrix(this), v1.getE(v2));
608 v1e.getE(v2e).bindTo(e.pair.getBindingMatrix(this.pair), v2.getE(v1));
613 public void bindingGroupChanged() {
614 HashSet<E> nbg = new HashSet<E>();
615 for(E eother : (Iterable<E>)getBoundPeers()) nbg.add(eother);
616 for(E eother : nbg) {
617 if (next==null || prev==null) continue;
618 if (eother.next==null || eother.prev==null) continue;
620 if (next.isBoundTo(eother.pair.prev.pair) && !prev.isBoundTo(eother.pair.next.pair))
621 prev.bindTo(next.getBindingMatrix(eother.pair.prev.pair), eother.pair.next.pair);
622 if (!next.isBoundTo(eother.pair.prev.pair) && prev.isBoundTo(eother.pair.next.pair))
623 next.bindTo(prev.getBindingMatrix(eother.pair.next.pair), eother.pair.prev.pair);
626 if (next.isBoundTo(eother.prev) && !prev.isBoundTo(eother.next))
627 prev.bindTo(next.getBindingMatrix(eother.prev), eother.next);
628 if (!next.isBoundTo(eother.prev) && prev.isBoundTo(eother.next))
629 next.bindTo(prev.getBindingMatrix(eother.next), eother.prev);
631 if (next.isBoundTo(eother.next) && !prev.isBoundTo(eother.prev))
632 prev.bindTo(next.getBindingMatrix(eother.next), eother.prev);
633 if (!next.isBoundTo(eother.next) && prev.isBoundTo(eother.prev))
634 next.bindTo(prev.getBindingMatrix(eother.prev), eother.next);
639 public float stretchRatio() {
640 Vertex nearest = error_against.nearest(midpoint());
641 float nearest_distance = midpoint().distance(nearest.p);
642 float other_distance =
643 (v1.p.distance(error_against.nearest(v1.p).p)+
644 v2.p.distance(error_against.nearest(v2.p).p))/2;
645 return nearest_distance/other_distance;
647 public float comparator() {
650 public int compareTo(E e) {
651 return e.comparator() > comparator() ? 1 : -1;
653 public void bindEdge(E e, Matrix m) {
655 pair._bindEdge(e.pair, m);
657 public void _bindEdge(E e, Matrix m) {
660 //assumes edges are identical length at binding time
661 Vec reflectionPlaneNormal = e.v2.p.minus(e.v1.p).norm();
662 float a = reflectionPlaneNormal.x;
663 float b = reflectionPlaneNormal.y;
664 float c = reflectionPlaneNormal.z;
665 Matrix reflectionMatrix =
666 new Matrix( 1-2*a*a, -2*a*b, -2*a*c, 0,
667 -2*a*b, 1-2*b*b, -2*b*c, 0,
668 -2*a*c, -2*b*c, 1-2*c*c, 0,
670 m = m.times(Matrix.translate(e.midpoint().minus(Point.ORIGIN))
671 .times(reflectionMatrix)
672 .times(Matrix.translate(Point.ORIGIN.minus(e.midpoint()))));
673 System.out.println(reflectionPlaneNormal);
674 System.out.println(" " + v1.p + " " + m.times(e.v1.p));
675 System.out.println(" " + v2.p + " " + m.times(e.v2.p));
678 if (m.times(e.v1.p).minus(v1.p).mag() > EPSILON) throw new Error();
679 if (m.times(e.v2.p).minus(v2.p).mag() > EPSILON) throw new Error();
684 public void dobind() {
685 for(E e : (Iterable<E>)getBoundPeers()) {
686 if (e==this) continue;
687 v1.bindTo(getBindingMatrix(e), e.v1);
688 v2.bindTo(getBindingMatrix(e), e.v2);
690 e.v1.setConstraint(getAffineConstraint());
691 e.v2.setConstraint(getAffineConstraint());
696 public Vertex shatter() {
697 if (shattered || destroyed) return nearest(midpoint());
703 for(E e : (Iterable<E>)getBoundPeers()) {
706 E pnext = e.pair.next;
707 E pprev = e.pair.prev;
708 Point mid = e.midpoint();
709 Vertex r = e.next.v2;
710 Vertex l = e.pair.next.v2;
714 newT(r.p, e.v1.p, mid, null, 0);
715 newT(r.p, mid, e.v2.p, null, 0);
716 newT(l.p, mid, e.v1.p, null, 0);
717 newT(l.p, e.v2.p, mid, null, 0);
720 for(E e : (Iterable<E>)getBoundPeers()) {
721 Point mid = e.midpoint();
723 first = e.v1.getE(mid);
726 firstq = e.v2.getE(mid).pair;
729 e.v1.getE(mid). bindTo(e.getBindingMatrix(firste), first);
730 e.v1.getE(mid).pair. bindTo(e.getBindingMatrix(firste), first.pair);
731 e.v2.getE(mid).pair. bindTo(e.getBindingMatrix(firste), firstq);
732 e.v2.getE(mid).pair.pair.bindTo(e.getBindingMatrix(firste), firstq.pair);
735 first.setConstraint(firste.getAffineConstraint());
736 firstq.setConstraint(firste.getAffineConstraint());
738 return nearest(midpoint());
741 public boolean destroyed = false;
742 public void destroy() {
743 if (destroyed) return;
745 pair.destroyed = true;
747 if (t != null) t.destroy();
750 if (pair.t != null) pair.t.destroy();
753 if (next.t != null) next.t.destroy();
754 if (prev.t != null) prev.t.destroy();
758 if (pair.next.t != null) pair.next.t.destroy();
759 if (pair.prev.t != null) pair.next.t.destroy();
763 pair.prev.next = next;
764 next.prev = pair.prev;
765 prev.next = pair.next;
766 pair.next.prev = prev;
768 if (v1.e == this) v1.e = pair.next;
769 if (pair.v1.e == pair) pair.v1.e = next;
771 if (v2.e == this) throw new RuntimeException();
772 if (pair.v2.e == pair) throw new RuntimeException();
796 private void sync() {
797 this.prev.next = this;
798 this.next.prev = this;
799 this.pair.pair = this;
800 if (this.next.v1 != v2) throw new Error();
801 if (this.prev.v2 != v1) throw new Error();
802 if (this.v1.e == null) this.v1.e = this;
803 if (!added) added = true;
805 private boolean added = false;
807 public T makeT(int colorclass) { return t==null ? (t = new T(this, colorclass)) : t; }
809 public double dihedralAngle() {
810 Vec v1 = t.norm().times(-1);
811 Vec v2 = pair.t.norm().times(-1);
812 double prod = v1.norm().dot(v2.norm());
813 prod = Math.min(1,prod);
814 prod = Math.max(-1,prod);
815 double ret = Math.acos(prod);
816 if (Double.isNaN(ret)) throw new Error("nan! " + prod);
820 /** angle between this half-edge and the next */
821 public double angle() {
822 Vec v1 = next.v2.p.minus(this.v2.p);
823 Vec v2 = this.v1.p.minus(this.v2.p);
824 return Math.acos(v1.norm().dot(v2.norm()));
827 public Vertex getOther(Vertex v) {
828 if (this.v1 == v) return v2;
829 if (this.v2 == v) return v1;
833 public void makeAdjacent(E e) {
834 if (this.next == e) return;
835 if (v2 != e.v1) throw new Error("cannot make adjacent -- no shared vertex: " + this + " " + e);
836 if (t != null || e.t != null) throw new Error("cannot make adjacent -- edges not both free " + t + " " + e.t);
838 E freeIncident = v2.getFreeIncident(e, this);
840 e.prev.next = freeIncident.next;
841 freeIncident.next.prev = e.prev;
843 freeIncident.next = this.next;
844 this.next.prev = freeIncident;
853 /** creates an isolated edge out in the middle of space */
854 public E(Point v1, Point v2) {
855 if (vertices.get(v1) != null) throw new Error();
856 if (vertices.get(v2) != null) throw new Error();
857 this.v1 = new Vertex(v1);
858 this.v2 = new Vertex(v2);
859 this.prev = this.next = this.pair = new E(this, this, this);
861 this.v2.e = this.pair;
865 /** adds a new half-edge from prev.v2 to v2 */
866 public E(E prev, Point p) {
868 v2 = vertices.get(p);
869 if (v2 == null) v2 = new Vertex(p);
873 if (prev.destroyed) throw new RuntimeException();
874 if (v2.getE(v1) != null) throw new Error();
876 this.next = this.pair = new E(this, this, prev.next);
878 E q = v2.getFreeIncident();
880 this.next.prev = this;
882 this.prev.next = this;
883 this.pair = new E(q, this, z);
885 if (v2.e==null) v2.e = this.pair;
889 /** adds a new half-edge to the mesh with a given predecessor, successor, and pair */
890 public E(E prev, E pair, E next) {
893 if (prev.destroyed) throw new RuntimeException();
899 public Point midpoint() { return new Point((v1.p.x+v2.p.x)/2, (v1.p.y+v2.p.y)/2, (v1.p.z+v2.p.z)/2); }
900 public boolean has(Vertex v) { return v==v1 || v==v2; }
901 public float length() { return v1.p.minus(v2.p).mag(); }
902 public String toString() { return v1+"->"+v2; }
906 public E makeE(Point p1, Point p2) {
907 Vertex v1 = vertices.get(p1);
908 Vertex v2 = vertices.get(p2);
909 if (v1 != null && v2 != null) {
911 if (e != null) return e;
913 if (e != null) return e;
915 if (v1 != null) return new E(v1.getFreeIncident(), p2);
916 if (v2 != null) return new E(v2.getFreeIncident(), p1).pair;
917 return new E(p1, p2);
919 public boolean coalesce = false;
920 private static float round(float f) {
921 return Math.round(f*1000)/1000f;
923 public T newT(HasPoint v1, HasPoint v2, HasPoint v3) {
924 return newT(v1.getPoint(), v2.getPoint(), v3.getPoint(), null, 0);
926 public T newT(Point v1, Point v2, Point v3, Vec norm, int colorclass) {
929 for(Vertex v : vertices) { if (v1.distance(v.p) < EPSILON) { v1 = v.p; break; } }
930 for(Vertex v : vertices) { if (v2.distance(v.p) < EPSILON) { v2 = v.p; break; } }
931 for(Vertex v : vertices) { if (v3.distance(v.p) < EPSILON) { v3 = v.p; break; } }
933 v1 = new Point(round(v1.x), round(v1.y), round(v1.z));
934 v2 = new Point(round(v2.x), round(v2.y), round(v2.z));
935 v3 = new Point(round(v3.x), round(v3.y), round(v3.z));
939 Vec norm2 = v3.minus(v1).cross(v2.minus(v1));
940 float dot = norm.dot(norm2);
941 //if (Math.abs(dot) < EPointSILON) throw new Error("dot products within evertsilon of each other: "+norm+" "+norm2);
942 if (dot < 0) { Point p = v1; v1=v2; v2 = p; }
944 E e12 = makeE(v1, v2);
945 E e23 = makeE(v2, v3);
946 E e31 = makeE(v3, v1);
947 while(e12.next != e23 || e23.next != e31 || e31.next != e12) {
948 e12.makeAdjacent(e23);
949 e23.makeAdjacent(e31);
950 e31.makeAdjacent(e12);
952 T ret = e12.makeT(colorclass);
953 if (e12.t == null) throw new Error();
954 if (e23.t == null) throw new Error();
955 if (e31.t == null) throw new Error();
959 private int max_serial = 0;
960 /** [UNIQUE] a triangle (face) */
961 public final class T extends Triangle {
963 public final int color;
964 public final int colorclass;
966 public boolean red = false;
967 public boolean old = false;
969 public final int serial = max_serial++;
970 public boolean occluded;
972 public Point shatter() {
973 if (destroyed) return null;
976 HashSet<E> forward = new HashSet<E>();
977 HashSet<E> backward = new HashSet<E>();
978 HashSet<E> both = new HashSet<E>();
980 for(E eb : (Iterable<E>)e.getBoundPeers()) {
982 if (eb.next.isBoundTo(e.next) && eb.prev.isBoundTo(e.prev)) {
986 if (eb.pair.next.pair.isBoundTo(e.prev) && eb.pair.prev.pair.isBoundTo(e.next)) {
987 backward.add(eb.pair);
992 Vertex v1 = e.t.v1();
993 Vertex v2 = e.t.v2();
994 Vertex v3 = e.t.v3();
995 Point c = e.t.centroid();
1003 // FIXME: forward too
1004 for(E ex : backward) {
1005 Vertex v1x = ex.t.v1();
1006 Vertex v2x = ex.t.v2();
1007 Vertex v3x = ex.t.v3();
1008 Point cx = ex.t.centroid();
1009 E ex_next = ex.next;
1010 E ex_prev = ex.prev;
1016 // FIXME: i have no idea if this is right
1017 e.next.bindTo(e.getBindingMatrix(ex.pair), ex.prev);
1018 e.prev.bindTo(e.getBindingMatrix(ex.pair), ex.next);
1019 e.next.pair.bindTo(e.getBindingMatrix(ex.pair), ex.prev.pair);
1020 e.prev.pair.bindTo(e.getBindingMatrix(ex.pair), ex.next.pair);
1022 e_next.next.bindTo(e_next.getBindingMatrix(ex_prev.pair), ex_prev.prev.pair);
1023 e_next.prev.bindTo(e_next.getBindingMatrix(ex_prev.pair), ex_prev.next.pair);
1025 e_prev.next.bindTo(e_prev.getBindingMatrix(ex_next.pair), ex_next.prev.pair);
1026 e_prev.prev.bindTo(e_prev.getBindingMatrix(ex_next.pair), ex_next.next.pair);
1035 for(E e : (Iterable<E>)getBoundPeers()) {
1038 E pnext = e.pair.next;
1039 E pprev = e.pair.prev;
1040 Point mid = e.midpoint();
1041 Vertex r = e.next.v2;
1042 Vertex l = e.pair.next.v2;
1046 newT(r.p, e.v1.p, mid, null, 0);
1047 newT(r.p, mid, e.v2.p, null, 0);
1048 newT(l.p, mid, e.v1.p, null, 0);
1049 newT(l.p, e.v2.p, mid, null, 0);
1052 for(E e : (Iterable<E>)getBoundPeers()) {
1053 Point mid = e.midpoint();
1055 first = e.v1.getE(mid);
1058 firstq = e.v2.getE(mid).pair;
1061 e.v1.getE(mid). bindTo(e.getBindingMatrix(firste), first);
1062 e.v1.getE(mid).pair. bindTo(e.getBindingMatrix(firste), first.pair);
1063 e.v2.getE(mid).pair. bindTo(e.getBindingMatrix(firste), firstq);
1064 e.v2.getE(mid).pair.pair.bindTo(e.getBindingMatrix(firste), firstq.pair);
1068 first.setConstraint(firste.getAffineConstraint());
1069 firstq.setConstraint(firste.getAffineConstraint());
1075 T(E e1, int colorclass) {
1079 if (e1==e2 || e1==e3) throw new Error();
1080 if (e3.next!=e1) throw new Error();
1081 if (e1.t!=null || e2.t!=null || e3.t!=null) throw new Error("non-manifold surface or disagreeing normals");
1084 e1.next.next.t = this;
1086 // FIXME: check for sealed/watertight surface once construction is complete (and infer normal(s)?)
1088 int color = Math.abs(random.nextInt());
1091 if (e1().pair.t != null && color == e1().pair.t.color) { color++; continue; }
1092 if (e2().pair.t != null && color == e2().pair.t.color) { color++; continue; }
1093 if (e3().pair.t != null && color == e3().pair.t.color) { color++; continue; }
1097 this.colorclass = colorclass;
1098 triangles.add(this);
1100 public E e1() { return e1; }
1101 public E e2() { return e1.next; }
1102 public E e3() { return e1.prev; }
1103 public Vertex v1() { return e1.v1; }
1104 public Vertex v2() { return e1.v2; }
1105 public Vertex v3() { return e1.next.v2; }
1106 public Point p1() { return e1.v1.p; }
1107 public Point p2() { return e1.v2.p; }
1108 public Point p3() { return e1.next.v2.p; }
1109 public boolean hasE(E e) { return e1==e || e1.next==e || e1.prev==e; }
1110 public boolean has(Vertex v) { return v1()==v || v2()==v || v3()==v; }
1112 public Vertex getOtherVertex(E e) {
1113 if (!hasE(e)) throw new RuntimeException();
1114 if (!e.has(v1())) return v1();
1115 if (!e.has(v2())) return v2();
1116 if (!e.has(v3())) return v3();
1117 throw new RuntimeException();
1120 public void removeFromRTree() { triangles.remove(this); }
1121 public void addToRTree() { triangles.insert(this); }
1122 public void destroy() {
1128 triangles.remove(this);
1131 public void reinsert() { triangles.remove(this); triangles.add(this); }
1133 private boolean destroyed = false;
1134 public boolean destroyed() { return destroyed; }
1136 public boolean shouldBeDrawn() {
1138 if (e1().bindingGroupSize() <= 1) return false;
1139 if (e2().bindingGroupSize() <= 1) return false;
1140 if (e3().bindingGroupSize() <= 1) return false;
1145 public void glTriangle(GL gl, Matrix m) {
1146 gl.glPushName(serial);
1147 gl.glBegin(GL.GL_TRIANGLES);
1153 /** issue gl.glVertex() for each of the triangle's points */
1154 public void glVertices(GL gl, Matrix m) {
1155 if (!shouldBeDrawn()) return;
1156 super.glVertices(gl, m);