#include "SMDS_Mesh.hxx"
#include "SMDS_MeshElement.hxx"
#include "SMDS_MeshNode.hxx"
+#include "SMDS_PolygonalFaceOfNodes.hxx"
#include "SMDS_SetIterator.hxx"
#include "SMDS_VolumeTool.hxx"
#include "SMESH_File.hxx"
#include "SMESH_TypeDefs.hxx"
-//#include "utilities.h"
+#include <Standard_ErrorHandler.hxx>
+#include <Standard_Failure.hxx>
+#include <gp_Ax2.hxx>
#include <limits>
return aResult;
}
+
//================================================================================
/*!
* \brief Destructor deletes temporary faces
DriverSTL_W_SMDS_Mesh::~DriverSTL_W_SMDS_Mesh()
{
- for ( unsigned i = 0; i < myVolumeTrias.size(); ++i )
- delete myVolumeTrias[i];
+ for ( unsigned i = 0; i < myVolumeFacets.size(); ++i )
+ delete myVolumeFacets[i];
}
//================================================================================
void DriverSTL_W_SMDS_Mesh::findVolumeTriangles()
{
+ myNbVolumeTrias = 0;
+
SMDS_VolumeTool theVolume;
SMDS_VolumeIteratorPtr vIt = myMesh->volumesIterator();
std::vector< const SMDS_MeshNode*> nodes;
const SMDS_MeshNode** n = theVolume.GetFaceNodes(iF);
int nbN = theVolume.NbFaceNodes(iF);
nodes.assign( n, n+nbN );
- if ( !myMesh->FindElement( nodes, SMDSAbs_Face, /*Nomedium=*/false))
+ if ( !myMesh->FindElement( nodes, SMDSAbs_Face, /*noMedium=*/false))
{
- if ( nbN == 9 && !theVolume.IsPoly() ) // facet is SMDSEntity_BiQuad_Quadrangle
+ if (( nbN == 9 || nbN == 7 ) &&
+ ( !theVolume.IsPoly() )) // facet is bi-quaratic
{
int nbTria = nbN - 1;
for ( int iT = 0; iT < nbTria; ++iT )
- myVolumeTrias.push_back( new SMDS_FaceOfNodes( n[8], n[0+iT], n[1+iT] ));
+ myVolumeFacets.push_back( new SMDS_FaceOfNodes( n[8], n[0+iT], n[1+iT] ));
+ myNbVolumeTrias += nbTria;
}
else
{
- int nbTria = nbN - 2;
- for ( int iT = 0; iT < nbTria; ++iT )
- myVolumeTrias.push_back( new SMDS_FaceOfNodes( n[0], n[1+iT], n[2+iT] ));
+ myVolumeFacets.push_back( new SMDS_PolygonalFaceOfNodes( nodes ));
+ myNbVolumeTrias += nbN - 2;
}
}
}
SMDS_ElemIteratorPtr DriverSTL_W_SMDS_Mesh::getFaces() const
{
SMDS_ElemIteratorPtr facesIter = myMesh->elementsIterator(SMDSAbs_Face);
- SMDS_ElemIteratorPtr tmpTriaIter( new SMDS_ElementVectorIterator( myVolumeTrias.begin(),
- myVolumeTrias.end()));
+ SMDS_ElemIteratorPtr tmpTriaIter( new SMDS_ElementVectorIterator( myVolumeFacets.begin(),
+ myVolumeFacets.end()));
typedef std::vector< SMDS_ElemIteratorPtr > TElemIterVector;
TElemIterVector iters(2);
iters[0] = facesIter;
return n;
}
+namespace
+{
+ /*!
+ * \brief Vertex of a polygon. Together with 2 neighbor Vertices represents a triangle
+ */
+ struct PolyVertex
+ {
+ SMESH_TNodeXYZ _nxyz;
+ gp_XY _xy;
+ PolyVertex* _prev;
+ PolyVertex* _next;
+
+ void SetNodeAndNext( const SMDS_MeshNode* n, PolyVertex& v )
+ {
+ _nxyz.Set( n );
+ _next = &v;
+ v._prev = this;
+ }
+ PolyVertex* Delete()
+ {
+ _prev->_next = _next;
+ _next->_prev = _prev;
+ return _next;
+ }
+ void GetTriaNodes( const SMDS_MeshNode** nodes) const
+ {
+ nodes[0] = _prev->_nxyz._node;
+ nodes[1] = this->_nxyz._node;
+ nodes[2] = _next->_nxyz._node;
+ }
+
+ inline static double Area( const PolyVertex* v0, const PolyVertex* v1, const PolyVertex* v2 )
+ {
+ gp_XY vPrev = v0->_xy - v1->_xy;
+ gp_XY vNext = v2->_xy - v1->_xy;
+ return vNext ^ vPrev;
+ }
+ double TriaArea() const { return Area( _prev, this, _next ); }
+
+ bool IsInsideTria( const PolyVertex* v )
+ {
+ gp_XY p = _prev->_xy - v->_xy;
+ gp_XY t = this->_xy - v->_xy;
+ gp_XY n = _next->_xy - v->_xy;
+ return (( p ^ t ) > 0 &&
+ ( t ^ n ) > 0 &&
+ ( n ^ p ) > 0 );
+ // return ( Area( _prev, this, v ) > 0 &&
+ // Area( this, _next, v ) > 0 &&
+ // Area( _next, _prev, v ) > 0 );
+ }
+ };
+
+ //================================================================================
+ /*!
+ * \brief Triangulate a polygon. Assure correct orientation for concave polygons
+ */
+ //================================================================================
+
+ bool triangulate( std::vector< const SMDS_MeshNode*>& nodes, const size_t nbNodes )
+ {
+ // connect nodes into a ring
+ std::vector< PolyVertex > pv( nbNodes );
+ for ( size_t i = 1; i < nbNodes; ++i )
+ pv[i-1].SetNodeAndNext( nodes[i-1], pv[i] );
+ pv[ nbNodes-1 ].SetNodeAndNext( nodes[ nbNodes-1 ], pv[0] );
+
+ // get a polygon normal
+ gp_XYZ normal(0,0,0), p0,v01,v02;
+ p0 = pv[0]._nxyz;
+ v01 = pv[1]._nxyz - p0;
+ for ( size_t i = 2; i < nbNodes; ++i )
+ {
+ v02 = pv[i]._nxyz - p0;
+ normal += v01 ^ v02;
+ v01 = v02;
+ }
+ // project nodes to the found plane
+ gp_Ax2 axes;
+ try {
+ axes = gp_Ax2( p0, normal, v01 );
+ }
+ catch ( Standard_Failure ) {
+ return false;
+ }
+ for ( size_t i = 0; i < nbNodes; ++i )
+ {
+ gp_XYZ p = pv[i]._nxyz - p0;
+ pv[i]._xy.SetX( axes.XDirection().XYZ() * p );
+ pv[i]._xy.SetY( axes.YDirection().XYZ() * p );
+ }
+
+ // in a loop, find triangles with positive area and having no vertices inside
+ int iN = 0, nbTria = nbNodes - 2;
+ nodes.reserve( nbTria * 3 );
+ const double minArea = 1e-6;
+ PolyVertex* v = &pv[0], *vi;
+ int nbVertices = nbNodes, nbBadTria = 0, isGoodTria;
+ while ( nbBadTria < nbVertices )
+ {
+ if (( isGoodTria = v->TriaArea() > minArea ))
+ {
+ for ( vi = v->_next->_next;
+ vi != v->_prev;
+ vi = vi->_next )
+ {
+ if ( v->IsInsideTria( vi ))
+ break;
+ }
+ isGoodTria = ( vi == v->_prev );
+ }
+ if ( isGoodTria )
+ {
+ v->GetTriaNodes( &nodes[ iN ] );
+ iN += 3;
+ v = v->Delete();
+ if ( --nbVertices == 3 )
+ {
+ // last triangle remains
+ v->GetTriaNodes( &nodes[ iN ] );
+ return true;
+ }
+ nbBadTria = 0;
+ }
+ else
+ {
+ v = v->_next;
+ ++nbBadTria;
+ }
+ }
+ return false;
+
+ } // triangulate()
+} // namespace
+
//================================================================================
/*!
* \brief Return nb triangles in a decomposed mesh face
*/
//================================================================================
-static int getTriangles( const SMDS_MeshElement* face,
- const SMDS_MeshNode** nodes)
+static int getTriangles( const SMDS_MeshElement* face,
+ std::vector< const SMDS_MeshNode*>& nodes)
{
// WARNING: decomposing into triangles must be coherent with getNbTriangles()
- int nbTria, i = 0;
+ int nbTria, i = 0, nbNodes = face->NbNodes();
SMDS_NodeIteratorPtr nIt = face->interlacedNodesIterator();
+ nodes.resize( nbNodes * 3 );
nodes[ i++ ] = nIt->next();
nodes[ i++ ] = nIt->next();
nodes[ i++ ] = nodes[ 0 ];
nodes[ i++ ] = nodes[ 2 ];
break;
+ case SMDSEntity_Triangle:
+ nbTria = 1;
+ nodes[ i++ ] = nIt->next();
+ break;
default:
- // case SMDSEntity_Triangle:
// case SMDSEntity_Quad_Triangle:
// case SMDSEntity_Quadrangle:
// case SMDSEntity_Quad_Quadrangle:
// case SMDSEntity_Polygon:
// case SMDSEntity_Quad_Polygon:
- nbTria = face->NbNodes() - 2;
- nodes[ i++ ] = nIt->next();
- while ( i < 3*nbTria )
- {
- nodes[ i++ ] = nodes[ 0 ];
- nodes[ i++ ] = nodes[ i-2 ];
+ nbTria = nbNodes - 2;
+ while ( nIt->more() )
nodes[ i++ ] = nIt->next();
+
+ if ( !triangulate( nodes, nbNodes ))
+ {
+ nIt = face->interlacedNodesIterator();
+ nodes[ 0 ] = nIt->next();
+ nodes[ 1 ] = nIt->next();
+ nodes[ 2 ] = nIt->next();
+ for ( i = 3; i < 3*nbTria; i += 3 )
+ {
+ nodes[ i+0 ] = nodes[ 0 ];
+ nodes[ i+1 ] = nodes[ i-1 ];
+ nodes[ i+2 ] = nIt->next();
+ }
}
break;
}
aFile.writeRaw( buf.c_str(), buf.size() );
char sval[128];
- const SMDS_MeshNode* triaNodes[2048];
+ std::vector< const SMDS_MeshNode* > triaNodes;
SMDS_ElemIteratorPtr itFaces = getFaces();
while ( itFaces->more() )
aFile.openForWriting();
// we first count the number of triangles
- int nbTri = myVolumeTrias.size();
+ int nbTri = myNbVolumeTrias;
{
SMDS_FaceIteratorPtr itFaces = myMesh->facesIterator();
while ( itFaces->more() ) {
int dum=0;
- const SMDS_MeshNode* triaNodes[2048];
+ std::vector< const SMDS_MeshNode* > triaNodes;
SMDS_ElemIteratorPtr itFaces = getFaces();
while ( itFaces->more() )
