bool Triangulate::Process(const Vector2fVector &contour,Vector2fVector &result)
{
/* allocate and initialize list of Vertices in polygon */
int n = contour.size();
if ( n < 3 ) return false;
int *V = new int[n];
/* we want a counter-clockwise polygon in V */
if ( 0.0f < Area(contour) )
for (int v=0; v<n; v++) V[v] = v;
else
for(int v=0; v<n; v++) V[v] = (n-1)-v;
int nv = n;
/* remove nv-2 Vertices, creating 1 triangle every time */
int count = 2*nv; /* error detection */
for(int m=0, v=nv-1; nv>2; )
{
/* if we loop, it is probably a non-simple polygon */
if (0 >= (count--))
{
//** Triangulate: ERROR - probable bad polygon!
return false;
}
/* three consecutive vertices in current polygon, <u,v,w> */
int u = v ; if (nv <= u) u = 0; /* previous */
v = u+1; if (nv <= v) v = 0; /* new v */
int w = v+1; if (nv <= w) w = 0; /* next */
if ( Snip(contour,u,v,w,nv,V) )
{
int a,b,c,s,t;
/* true names of the vertices */
a = V[u]; b = V[v]; c = V[w];
/* output Triangle */
result.push_back( contour[a] );
result.push_back( contour[b] );
result.push_back( contour[c] );
m++;
/* remove v from remaining polygon */
for(s=v,t=v+1;t<nv;s++,t++) V[s] = V[t]; nv--;
/* resest error detection counter */
count = 2*nv;
}
}
delete V;
return true;
}
bool Triangulate::Process(const Vector2dVector &contour,Vector2dVector &result)
{
#if defined(PRECISE_TRIANGULATION)
std::vector<p2t::Point*> _polyline;
for (auto _p : contour){
_polyline.push_back(new p2t::Point(_p.GetX(), _p.GetY()));
}
p2t::CDT* _cdt = new p2t::CDT(_polyline);
_cdt->Triangulate();
std::vector<p2t::Triangle*> _triangles = _cdt->GetTriangles();
for (auto _t : _triangles){
auto _pt1 = _t->GetPoint(0);
auto _pt2 = _t->GetPoint(1);
auto _pt3 = _t->GetPoint(2);
result.push_back(Vector2d(_pt1->x, _pt1->y));
result.push_back(Vector2d(_pt2->x, _pt2->y));
result.push_back(Vector2d(_pt3->x, _pt3->y));
}
delete _cdt;
for (auto _p : _polyline)
delete _p;
return true;
#else
/* allocate and initialize list of Vertices in polygon */
int n = (int)contour.size();
if ( n < 3 ) return false;
int *V = new int[n];
/* we want a counter-clockwise polygon in V */
if ( 0.0f < Area(contour) )
for (int v=0; v<n; v++) V[v] = v;
else
for(int v=0; v<n; v++) V[v] = (n-1)-v;
int nv = n;
/* remove nv-2 Vertices, creating 1 triangle every time */
int count = 2*nv; /* error detection */
for(int m=0, v=nv-1; nv>2; )
{
/* if we loop, it is probably a non-simple polygon */
if (0 >= (count--))
{
//** Triangulate: ERROR - probable bad polygon!
return false;
}
/* three consecutive vertices in current polygon, <u,v,w> */
int u = v ; if (nv <= u) u = 0; /* previous */
v = u+1; if (nv <= v) v = 0; /* new v */
int w = v+1; if (nv <= w) w = 0; /* next */
if ( Snip(contour,u,v,w,nv,V) )
{
int a,b,c,s,t;
/* true names of the vertices */
a = V[u]; b = V[v]; c = V[w];
/* output Triangle */
result.push_back( contour[a] );
result.push_back( contour[b] );
result.push_back( contour[c] );
m++;
/* remove v from remaining polygon */
for(s=v,t=v+1;t<nv;s++,t++) V[s] = V[t]; nv--;
/* resest error detection counter */
count = 2*nv;
}
}
//Danilo S Carvalho Alteration from delete to delete[]
delete[] V;
return true;
#endif
}
