bool Delaunay2dMesh::buildMesh( const std::vector<CCVector2>& points2D,
const std::vector<int>& segments2D,
char* outputErrorStr/*=0*/)
{
#if defined(USE_CGAL_LIB)
//CGAL boilerplate
typedef CGAL::Exact_predicates_inexact_constructions_kernel K;
//We define a vertex_base with info. The "info" (size_t) allow us to keep track of the original point index.
typedef CGAL::Triangulation_vertex_base_with_info_2<size_t, K> Vb;
typedef CGAL::Constrained_triangulation_face_base_2<K> Fb;
typedef CGAL::No_intersection_tag Itag; //This tag could ben changed if we decide to handle intersection
typedef CGAL::Triangulation_data_structure_2<Vb, Fb> Tds;
typedef CGAL::Constrained_Delaunay_triangulation_2<K, Tds, Itag> CDT;
typedef CDT::Point cgalPoint;
std::vector< std::pair<cgalPoint, size_t > > constraints;
size_t constrCount = segments2D.size();
try
{
constraints.reserve(constrCount);
} catch (const std::bad_alloc&)
{
if (outputErrorStr)
strcpy(outputErrorStr, "Not enough memory");
return false;
};
//We create the Constrained Delaunay Triangulation (CDT)
CDT cdt;
//We build the constraints
for(size_t i = 0; i < constrCount; ++i) {
const CCVector2 * pt = &points2D[segments2D[i]];
constraints.push_back(std::make_pair(cgalPoint(pt->x, pt->y), segments2D[i]));
}
//The CDT is built according to the constraints
cdt.insert(constraints.begin(), constraints.end());
m_numberOfTriangles = static_cast<unsigned >(cdt.number_of_faces());
m_triIndexes = new int[cdt.number_of_faces()*3];
//The cgal data structure is converted into CC one
if (m_numberOfTriangles > 0) {
int faceCount = 0;
for (CDT::Face_iterator face = cdt.faces_begin(); face != cdt.faces_end(); ++face, faceCount+=3) {
m_triIndexes[0+faceCount] = static_cast<int>(face->vertex(0)->info());
m_triIndexes[1+faceCount] = static_cast<int>(face->vertex(1)->info());
m_triIndexes[2+faceCount] = static_cast<int>(face->vertex(2)->info());
};
}
m_globalIterator = m_triIndexes;
m_globalIteratorEnd = m_triIndexes + 3*m_numberOfTriangles;
return true;
#else
if (outputErrorStr)
strcpy(outputErrorStr, "CGAL library not supported");
return false;
#endif
}
bool Delaunay2dMesh::buildMesh( const std::vector<CCVector2>& points2D,
const std::vector<int>& segments2D,
char* outputErrorStr/*=0*/)
{
#if defined(USE_TRIANGLE_LIB)
//we use the external library 'Triangle'
triangulateio in;
memset(&in,0,sizeof(triangulateio));
in.numberofpoints = static_cast<int>(points2D.size());
in.pointlist = (REAL*)(&points2D[0]);
in.segmentlist = (int*)(&segments2D[0]);
assert((segments2D.size() & 1) == 0);
in.numberofsegments = static_cast<int>(segments2D.size()/2);
triangulateio out;
memset(&out,0,sizeof(triangulateio));
try
{
triangulate ( "pczBPNIOQY", &in, &out, 0 );
}
catch (std::exception& e)
{
if (outputErrorStr)
strcpy(outputErrorStr,e.what());
return false;
}
catch (...)
{
if (outputErrorStr)
strcpy(outputErrorStr,"Unknown error");
return false;
}
m_numberOfTriangles = out.numberoftriangles;
if (m_numberOfTriangles > 0)
{
m_triIndexes = out.trianglelist;
//remove non existing points
int* _tri = out.trianglelist;
for (int i=0; i<out.numberoftriangles; )
{
if ( _tri[0] >= in.numberofpoints
|| _tri[1] >= in.numberofpoints
|| _tri[2] >= in.numberofpoints)
{
int lasTriIndex = (out.numberoftriangles-1) * 3;
_tri[0] = out.trianglelist[lasTriIndex + 0];
_tri[1] = out.trianglelist[lasTriIndex + 1];
_tri[2] = out.trianglelist[lasTriIndex + 2];
--out.numberoftriangles;
}
else
{
_tri += 3;
++i;
}
}
//Reduce memory size
if (out.numberoftriangles < static_cast<int>(m_numberOfTriangles))
{
assert(out.numberoftriangles > 0);
realloc(m_triIndexes, sizeof(int)*out.numberoftriangles*3);
m_numberOfTriangles = out.numberoftriangles;
}
}
trifree(out.segmentmarkerlist);
trifree(out.segmentlist);
m_globalIterator = m_triIndexes;
m_globalIteratorEnd = m_triIndexes + 3*m_numberOfTriangles;
return true;
#elif defined(USE_CGAL_LIB)
//CGAL boilerplate
typedef CGAL::Exact_predicates_inexact_constructions_kernel K;
//We define a vertex_base with info. The "info" (size_t) allow us to keep track of the original point index.
typedef CGAL::Triangulation_vertex_base_with_info_2<size_t, K> Vb;
typedef CGAL::Constrained_triangulation_face_base_2<K> Fb;
typedef CGAL::No_intersection_tag Itag; //This tag could ben changed if we decide to handle intersection
typedef CGAL::Triangulation_data_structure_2<Vb, Fb> Tds;
typedef CGAL::Constrained_Delaunay_triangulation_2<K, Tds, Itag> CDT;
typedef CDT::Point cgalPoint;
std::vector< std::pair<cgalPoint, size_t > > constraints;
size_t constrCount = segments2D.size();
try
{
constraints.reserve(constrCount);
} catch (const std::bad_alloc&)
{
if (outputErrorStr)
strcpy(outputErrorStr, "Not enough memory");
return false;
};
//We create the Constrained Delaunay Triangulation (CDT)
CDT cdt;
//We build the constraints
for(size_t i = 0; i < constrCount; ++i) {
const CCVector2 * pt = &points2D[segments2D[i]];
constraints.push_back(std::make_pair(cgalPoint(pt->x, pt->y), segments2D[i]));
}
//The CDT is built according to the constraints
cdt.insert(constraints.begin(), constraints.end());
m_numberOfTriangles = static_cast<unsigned >(cdt.number_of_faces());
m_triIndexes = new int[cdt.number_of_faces()*3];
//The cgal data structure is converted into CC one
if (m_numberOfTriangles > 0) {
int faceCount = 0;
for (CDT::Face_iterator face = cdt.faces_begin(); face != cdt.faces_end(); ++face, faceCount+=3) {
m_triIndexes[0+faceCount] = static_cast<int>(face->vertex(0)->info());
m_triIndexes[1+faceCount] = static_cast<int>(face->vertex(1)->info());
m_triIndexes[2+faceCount] = static_cast<int>(face->vertex(2)->info());
};
}
m_globalIterator = m_triIndexes;
m_globalIteratorEnd = m_triIndexes + 3*m_numberOfTriangles;
return true;
#else
if (outputErrorStr)
strcpy(outputErrorStr, "Triangle library not supported");
return false;
#endif
}
