bool Delaunay2dMesh::buildMesh( const std::vector<CCVector2>& points2D,
size_t pointCountToUse/*=0*/,
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::Triangulation_data_structure_2<Vb> Tds;
typedef CGAL::Delaunay_triangulation_2<K, Tds> DT;
typedef DT::Point cgalPoint;
std::vector< std::pair<cgalPoint, size_t > > pts;
size_t pointCount = points2D.size();
//we will use at most 'pointCountToUse' points (if not 0)
if (pointCountToUse > 0 && pointCountToUse < pointCount)
{
pointCount = pointCountToUse;
}
if (pointCount < 3)
{
if (outputErrorStr)
strcpy(outputErrorStr, "Not enough points");
return false;
}
try
{
pts.reserve(pointCount);
} catch (const std::bad_alloc&)
{
if (outputErrorStr)
strcpy(outputErrorStr, "Not enough memory");
return false;
};
m_numberOfTriangles = 0;
if (m_triIndexes)
{
delete[] m_triIndexes;
m_triIndexes = 0;
}
for(size_t i = 0; i < pointCount; ++i) {
const CCVector2 * pt = &points2D[i];
pts.push_back(std::make_pair(cgalPoint(pt->x, pt->y), i));
}
//The delaunay triangulation is built according to the 2D point cloud
DT dt(pts.begin(), pts.end());
m_numberOfTriangles = static_cast<unsigned >(dt.number_of_faces());
m_triIndexes = new int[dt.number_of_faces()*3];
//The cgal data structure is converted into CC one
if (m_numberOfTriangles > 0) {
int faceCount = 0;
for (DT::Face_iterator face = dt.faces_begin(); face != dt.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,
size_t pointCountToUse/*=0*/,
char* outputErrorStr/*=0*/)
{
#if defined(USE_TRIANGLE_LIB)
size_t pointCount = points2D.size();
//we will use at most 'pointCountToUse' points (if not 0)
if (pointCountToUse > 0 && pointCountToUse < pointCount)
{
pointCount = pointCountToUse;
}
if (pointCount < 3)
{
if (outputErrorStr)
strcpy(outputErrorStr, "Not enough points");
return false;
}
//reset
m_numberOfTriangles = 0;
if (m_triIndexes)
{
delete[] m_triIndexes;
m_triIndexes = 0;
}
//we use the external library 'Triangle'
triangulateio in;
memset(&in,0,sizeof(triangulateio));
in.numberofpoints = static_cast<int>(pointCount);
in.pointlist = (REAL*)(&points2D[0]);
//set static variable for 'triunsuitable' (for Triangle lib with '-u' option)
//s_maxSquareEdgeLength = maxEdgeLength*maxEdgeLength;
//DGM: doesn't work this way --> triangle lib will simply add new points!
try
{
triangulate ( "zQN", &in, &in, 0 );
}
catch (std::exception& e)
{
if (outputErrorStr)
strcpy(outputErrorStr,e.what());
return false;
}
catch (...)
{
if (outputErrorStr)
strcpy(outputErrorStr,"Unknown error");
return false;
}
m_numberOfTriangles = in.numberoftriangles;
if (m_numberOfTriangles > 0)
m_triIndexes = in.trianglelist;
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::Triangulation_data_structure_2<Vb> Tds;
typedef CGAL::Delaunay_triangulation_2<K, Tds> DT;
typedef DT::Point cgalPoint;
std::vector< std::pair<cgalPoint, size_t > > pts;
size_t pointCount = points2D.size();
//we will use at most 'pointCountToUse' points (if not 0)
if (pointCountToUse > 0 && pointCountToUse < pointCount)
{
pointCount = pointCountToUse;
}
if (pointCount < 3)
{
if (outputErrorStr)
strcpy(outputErrorStr, "Not enough points");
return false;
}
try
{
pts.reserve(pointCount);
} catch (const std::bad_alloc&)
{
if (outputErrorStr)
strcpy(outputErrorStr, "Not enough memory");
return false;
};
m_numberOfTriangles = 0;
if (m_triIndexes)
{
delete[] m_triIndexes;
m_triIndexes = 0;
}
for(size_t i = 0; i < pointCount; ++i) {
const CCVector2 * pt = &points2D[i];
pts.push_back(std::make_pair(cgalPoint(pt->x, pt->y), i));
}
//The delaunay triangulation is built according to the 2D point cloud
DT dt(pts.begin(), pts.end());
m_numberOfTriangles = static_cast<unsigned >(dt.number_of_faces());
m_triIndexes = new int[dt.number_of_faces()*3];
//The cgal data structure is converted into CC one
if (m_numberOfTriangles > 0) {
int faceCount = 0;
for (DT::Face_iterator face = dt.faces_begin(); face != dt.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, "Please link CC lib with either Triangle or CGAL");
return false;
#endif
}
