std::auto_ptr<QuadEdge>
QuadEdge::makeEdge(const Vertex &o, const Vertex &d)
{
QuadEdge *q0 = new QuadEdge();
//q1-q3 are free()'d by q0
QuadEdge *q1 = new QuadEdge();
QuadEdge *q2 = new QuadEdge();
QuadEdge *q3 = new QuadEdge();
q0->_rot = q1;
q1->_rot = q2;
q2->_rot = q3;
q3->_rot = q0;
q0->setNext(q0);
q1->setNext(q3);
q2->setNext(q2);
q3->setNext(q1);
QuadEdge *base = q0;
base->setOrig(o);
base->setDest(d);
return std::auto_ptr<QuadEdge>(base);
}
std::auto_ptr<QuadEdge>
QuadEdge::connect(QuadEdge &a, QuadEdge &b)
{
std::auto_ptr<QuadEdge> q0 = makeEdge(a.dest(), b.orig());
splice(*q0, a.lNext());
splice(q0->sym(), b);
return q0;
}
bool
QuadEdge::equalsOriented(const QuadEdge &qe) const
{
if (orig().getCoordinate().equals2D(qe.orig().getCoordinate())
&& dest().getCoordinate().equals2D(qe.dest().getCoordinate()))
return true;
return false;
}
QuadEdge *connect( QuadEdge *a, QuadEdge *b ) {
QuadEdge *e = makeEdge();
e->setOrg( a->Dest() );
e->setDest( b->Org() );
splice( e, a->Lnext() );
splice( e->Sym(), b );
return e;
}
bool
QuadEdge::equalsNonOriented(const QuadEdge &qe) const
{
if (equalsOriented(qe))
return true;
if (equalsOriented(qe.sym()))
return true;
return false;
}
bool
QuadEdge::testEqualQuadEdge(const QuadEdge& qe2)
{
/*
if(&qe1 == NULL && &qe2 == NULL)
{
return 1;
}
else if((&qe1==NULL && &qe2!=NULL) || (&qe1!=NULL && &qe2==NULL))
{
return 0;
}
*/
//when both of them are not null:
if((*_rot).testEqualQuadEdge(qe2.rot()) && (*next).testEqualQuadEdge(qe2.oNext()) //&& (*data == *(qe2.data))
&& (isAlive == qe2.isAlive) /*&& orig()==qe2.orig()*/)
return 1;
else
return 0;
}
void
QuadEdge::swap(QuadEdge &e)
{
QuadEdge &a = e.oPrev();
QuadEdge &b = e.sym().oPrev();
splice(e, a);
splice(e.sym(), b);
splice(e, a.lNext());
splice(e.sym(), b.lNext());
e.setOrig(a.dest());
e.setDest(b.dest());
}
void splice( QuadEdge *a, QuadEdge *b ) {
QuadEdge *alpha = a->Onext()->Rot();
QuadEdge *beta = b->Onext()->Rot();
QuadEdge *temp = a->Onext();
a->setOnext( b->Onext() );
b->setOnext( temp );
temp = alpha->Onext();
alpha->setOnext( beta->Onext() );
beta->setOnext( temp );
}
void Voronoi::onInit()
{
assert((vertices.size() == 0) && (edges.size() == 0) && "container should be empty");
// should check if p_boundary is empty.
//create boundary
p_boundary = { Vec2(0,0),Vec2(1,0),Vec2(1,1),Vec2(0,1) };
for (auto& p : p_boundary)
p = Vec2(
((p.x - 0.5) * 10 + 0.5)*boundary_rect.width + boundary_rect.left,
((p.y - 0.5) * 10 + 0.5)*boundary_rect.height + boundary_rect.top);
for (int i = 0; i < p_boundary.size(); i++)
{
auto v = createVertex(p_boundary[i]);
}
auto it_back_v = std::prev(vertices.end());
for (auto it = vertices.begin(); it != vertices.end(); it++)
{
QuadEdge* e = createEdge();
e->SetEndPoints(&*it_back_v, &*it);
(&*it_back_v)->e = &edges.back().e[0];
it_back_v = it;
}
auto it_back_e = std::prev(edges.end());
for (auto it = edges.begin(); it != edges.end(); it++)
{
QuadEdge::Splice((*it_back_e).e[0].Sym(), &(*it).e[0]);
it_back_e = it;
}
//triangulation
if (p_boundary.size() >= 4)
{
QuadEdge* e = &edges.begin()->e[0];
QuadEdge* e_end = e->Lprev()->Lprev();
e = e->Lnext();
do
{
QuadEdge* et = e->Lnext();
QuadEdge::Connect(createEdge(), e, e->Lprev());
e = et;
} while (e != e_end);
}
}
QuadEdge * Voronoi::LocateTriangleEdge(const Vec2 & p)
{
int i = 0;
QuadEdge* e = &edges.front().e[0];
while (true)
{
if (e->Org()->p == p || e->Dest()->p == p)
return e;
if (VoronoiMath::OnRight(e, p))
e = e->Sym();
else if (!VoronoiMath::OnRight(e->Onext(), p))
e = e->Onext();
else if (!VoronoiMath::OnRight(e->Dprev(), p))
e = e->Dprev();
else
return e;
if (++i > 100000)
break;
}
return nullptr;
}
void
QuadEdge::splice(QuadEdge &a, QuadEdge &b)
{
QuadEdge &alpha = a.oNext().rot();
QuadEdge &beta = b.oNext().rot();
QuadEdge &t1 = b.oNext();
QuadEdge &t2 = a.oNext();
QuadEdge &t3 = beta.oNext();
QuadEdge &t4 = alpha.oNext();
a.setNext(&t1);
b.setNext(&t2);
alpha.setNext(&t3);
beta.setNext(&t4);
}
QuadEdge& IncrementalDelaunayTriangulator::insertSite(const Vertex &v)
{
/**
* This code is based on Guibas and Stolfi (1985), with minor modifications
* and a bug fix from Dani Lischinski (Graphic Gems 1993). (The modification
* I believe is the test for the inserted site falling exactly on an
* existing edge. Without this test zero-width triangles have been observed
* to be created)
*/
QuadEdge *e = subdiv->locate(v);
if(!e) {
throw LocateFailureException("");
}
if (subdiv->isVertexOfEdge(*e, v)) {
// point is already in subdivision.
return *e;
}
else if (subdiv->isOnEdge(*e, v.getCoordinate())) {
// the point lies exactly on an edge, so delete the edge
// (it will be replaced by a pair of edges which have the point as a vertex)
e = &e->oPrev();
subdiv->remove(e->oNext());
}
/**
* Connect the new point to the vertices of the containing triangle
* (or quadrilateral, if the new point fell on an existing edge.)
*/
QuadEdge* base = &subdiv->makeEdge(e->orig(), v);
QuadEdge::splice(*base, *e);
QuadEdge *startEdge = base;
do {
base = &subdiv->connect(*e, base->sym());
e = &base->oPrev();
} while (&e->lNext() != startEdge);
// Examine suspect edges to ensure that the Delaunay condition
// is satisfied.
do {
QuadEdge* t = &e->oPrev();
if (t->dest().rightOf(*e) &&
v.isInCircle(e->orig(), t->dest(), e->dest())) {
QuadEdge::swap(*e);
e = &e->oPrev();
} else if (&e->oNext() == startEdge) {
return *base; // no more suspect edges.
} else {
e = &e->oNext().lPrev();
}
} while (true);
}
bool Vertex::leftOf(const QuadEdge &e) const {
return isCCW(e.orig(), e.dest());
}
Vertex* Voronoi::InsertPoint(const Vec2& p)
{
QuadEdge* e = LocateTriangleEdge(p);
if (e == nullptr ||
p == e->Org()->p || p == e->Dest()->p)
return nullptr;
else if (VoronoiMath::Collinear(e, p))
{
e = e->Oprev();
QuadEdge* et = e->Onext();
QuadEdge::Disconnect(et);
deleteEdge(et->RootEdge());
}
Vertex* v = createVertex(p);
v->e = e;
QuadEdge* e_begin = createEdge();
e_begin->SetEndPoints(e->Org(), v);
QuadEdge* et = e_begin;
QuadEdge::Splice(e_begin, e);
do
{
QuadEdge* et2 = createEdge();
QuadEdge::Connect(et2, e, et->Sym());
et = et2;
e = et->Oprev();
} while (e->Lnext() != e_begin);
do
{
et = e->Oprev();
if (VoronoiMath::OnRight(e, et->Dest()->p) &&
VoronoiMath::InCircle(e->Org()->p, et->Dest()->p, e->Dest()->p, p))
{
QuadEdge::Flip(e);
e = e->Oprev();
}
else if (e->Onext() == e_begin)
break;
else
e = e->Onext()->Lprev();
} while (true);
return v;
}
