RealDWG: Implementation of dumpAcDbSubDMesh

<?xml encoding=”UTF-8″>By Madhukar
Moogala

In RealDWG dumpDWG sample project [RealDWG 2018SamplesDumpDWG], dumpAcDbSubDMesh implementation is missing, I received a query from a ADN partner, so for the benefit of every one I blogging this.

Context: If input drawing to your RealDWG app contains Mesh elements, and you would like to view this elements in any other 3d viewer for example, OpenGL, this implementation will come handy.

void dumpAcDbSubDMesh(AcDbEntity *pEnt)
{
entInfo(pEnt, sizeof(AcDbSubDMesh));
if (pEnt->isKindOf(AcDbSubDMesh::desc()))
{
entInfo(pEnt, sizeof(AcDbSubDMesh));
AcDbSubDMesh *pMesh = AcDbSubDMesh::cast(pEnt);
Adesk::Int32  nFaces,
nEdges,
nVertices,
nSubFaces,
nSubVertices,
nSubdLevel;
bool bWaterTight;
Acad::ErrorStatus es = pMesh->numOfFaces(nFaces);
es = pMesh->numOfVertices(nVertices);
AcGePoint3d pt;
// this is just for simplicity instead of
//traversing all the vertices.
//if the vertices > 50 it increments by that number fold.
int increment = nVertices / 50;
if (!increment)increment++;
for (int i = 0; igetVertexAt(i, pt);
_print(_T("tt Vertex Points[%d] %g,%g,%gn"), i,
pt.x, pt.y, pt.z);
}
es = pMesh->numOfSubDividedFaces(nSubFaces);
es = pMesh->numOfSubDividedVertices(nSubVertices);
es = pMesh->isWatertight(bWaterTight);
es = pMesh->subdLevel(nSubdLevel);
es = pMesh->numOfEdges(nEdges);
AcGePoint3dArray nsubVerticesArray;
es = pMesh->getSubDividedVertices(nsubVerticesArray);
AcArray nsubfacesArray;
es = pMesh->getSubDividedFaceArray(nsubfacesArray);
// The content of the faces list is like so :
// [number of vertices of next face],
// ,
// e.g. [4], <1, 2, 3, 4>, [3], <1, 2, 3>, etc
for (int numVertices = 0,
i = 0;
i < nsubfacesArray.length();
i += numVertices + 1)
{
numVertices = nsubfacesArray.at(i);
// Let's print the edges of the face
_print(_T("t SubDMesh Edge Points n"));
_print(_T("tt Face vertex Points[%d] n"), numVertices);
for (int j = 0; j < numVertices; j++)
{
AcGePoint3d startPt =
nsubVerticesArray.at(nsubfacesArray.at(i + j + 1));
AcGePoint3d endPt =
nsubVerticesArray.at(nsubfacesArray.at(i + ((j + 1) % numVertices) + 1));
_print(_T("tt Vertex Points[%d] [{%g,%g,%g} ,{ %g,%g,%g }]n"), j,
startPt.x, startPt.y, startPt.z , endPt.x, endPt.y, endPt.z);
//Now you can draw lines using these points in OpenGl
}
}
}
}

Sample Output

SubDMesh Edge Points
Face vertex Points[4]
Vertex Points[0] [{10.1735,8.28866,16.5088} ,{ 16.5135,8.28866,16.5088 }]
Vertex Points[1] [{16.5135,8.28866,16.5088} ,{ 16.5135,11.4619,16.5088 }]
Vertex Points[2] [{16.5135,11.4619,16.5088} ,{ 10.1735,11.4619,16.5088 }]
Vertex Points[3] [{10.1735,11.4619,16.5088} ,{ 10.1735,8.28866,16.5088 }]
SubDMesh Edge Points
Face vertex Points[4]
Vertex Points[0] [{10.1735,5.11544,16.5088} ,{ 16.5135,5.11544,16.5088 }]
Vertex Points[1] [{16.5135,5.11544,16.5088} ,{ 16.5135,8.28866,16.5088 }]
Vertex Points[2] [{16.5135,8.28866,16.5088} ,{ 10.1735,8.28866,16.5088 }]
Vertex Points[3] [{10.1735,8.28866,16.5088} ,{ 10.1735,5.11544,16.5088 }]
SubDMesh Edge Points
Face vertex Points[4]
Vertex Points[0] [{10.1735,1.94223,16.5088} ,{ 16.5135,1.94223,16.5088 }]
Vertex Points[1] [{16.5135,1.94223,16.5088} ,{ 16.5135,5.11544,16.5088 }]
Vertex Points[2] [{16.5135,5.11544,16.5088} ,{ 10.1735,5.11544,16.5088 }]
Vertex Points[3] [{10.1735,5.11544,16.5088} ,{ 10.1735,1.94223,16.5088 }]
SubDMesh Edge Points
Face vertex Points[4]
Vertex Points[0] [{16.5135,8.28866,16.5088} ,{ 22.8534,8.28866,16.5088 }]
Vertex Points[1] [{22.8534,8.28866,16.5088} ,{ 22.8534,11.4619,16.5088 }]
Vertex Points[2] [{22.8534,11.4619,16.5088} ,{ 16.5135,11.4619,16.5088 }]
Vertex Points[3] [{16.5135,11.4619,16.5088} ,{ 16.5135,8.28866,16.5088 }]
SubDMesh Edge Points
Face vertex Points[4]
Vertex Points[0] [{16.5135,5.11544,16.5088} ,{ 22.8534,5.11544,16.5088 }]
Vertex Points[1] [{22.8534,5.11544,16.5088} ,{ 22.8534,8.28866,16.5088 }]
Vertex Points[2] [{22.8534,8.28866,16.5088} ,{ 16.5135,8.28866,16.5088 }]
Vertex Points[3] [{16.5135,8.28866,16.5088} ,{ 16.5135,5.11544,16.5088 }]
SubDMesh Edge Points
Face vertex Points[4]
Vertex Points[0] [{16.5135,1.94223,16.5088} ,{ 22.8534,1.94223,16.5088 }]
Vertex Points[1] [{22.8534,1.94223,16.5088} ,{ 22.8534,5.11544,16.5088 }]
Vertex Points[2] [{22.8534,5.11544,16.5088} ,{ 16.5135,5.11544,16.5088 }]
Vertex Points[3] [{16.5135,5.11544,16.5088} ,{ 16.5135,1.94223,16.5088 }]
SubDMesh Edge Points
Face vertex Points[4]
Vertex Points[0] [{22.8534,8.28866,16.5088} ,{ 29.1934,8.28866,16.5088 }]
Vertex Points[1] [{29.1934,8.28866,16.5088} ,{ 29.1934,11.4619,16.5088 }]
Vertex Points[2] [{29.1934,11.4619,16.5088} ,{ 22.8534,11.4619,16.5088 }]
Vertex Points[3] [{22.8534,11.4619,16.5088} ,{ 22.8534,8.28866,16.5088 }]
SubDMesh Edge Points
Face vertex Points[4]
Vertex Points[0] [{22.8534,5.11544,16.5088} ,{ 29.1934,5.11544,16.5088 }]
Vertex Points[1] [{29.1934,5.11544,16.5088} ,{ 29.1934,8.28866,16.5088 }]
Vertex Points[2] [{29.1934,8.28866,16.5088} ,{ 22.8534,8.28866,16.5088 }]
Vertex Points[3] [{22.8534,8.28866,16.5088} ,{ 22.8534,5.11544,16.5088 }]
SubDMesh Edge Points
Face vertex Points[4]
Vertex Points[0] [{22.8534,1.94223,16.5088} ,{ 29.1934,1.94223,16.5088 }]
Vertex Points[1] [{29.1934,1.94223,16.5088} ,{ 29.1934,5.11544,16.5088 }]
Vertex Points[2] [{29.1934,5.11544,16.5088} ,{ 22.8534,5.11544,16.5088 }]
Vertex Points[3] [{22.8534,5.11544,16.5088} ,{ 22.8534,1.94223,16.5088 }]