void Mesh::loadMeshdata(const std::string& a_Filepath)
{
Assimp::Importer importer;
const auto scene = importer.ReadFile(a_Filepath, aiPostProcessSteps::aiProcess_CalcTangentSpace |
aiPostProcessSteps::aiProcess_Triangulate |
aiPostProcessSteps::aiProcess_JoinIdenticalVertices |
aiPostProcessSteps::aiProcess_SortByPType);
auto error = importer.GetErrorString();
auto mesh = scene->mMeshes[0];
m_Vertices.reserve(mesh->mNumVertices);
for (auto i = 0u; i < mesh->mNumVertices; i++)
{
m_Vertices.emplace_back(toXMFloat3(mesh->mVertices[i]),
mesh->HasVertexColors(i) ? toXMFloat4(mesh->mColors[0][i]) : XMFLOAT4(1.0f, 1.0f, 1.0f, 1.0f),
mesh->HasTextureCoords(i) ? toXMFloat2(mesh->mTextureCoords[0][i]) : XMFLOAT2(0.0f, 0.0f));
}
m_Indices.reserve(mesh->mNumFaces * 3);
for (auto i = 0u; i < mesh->mNumFaces; ++i)
{
aiFace currentFace = mesh->mFaces[i];
for (auto j = 0u; j < currentFace.mNumIndices; ++j)
{
m_Indices.push_back(currentFace.mIndices[j]);
}
}
}
int ON_Mesh::GetConnectedComponents( bool bUseVertexConnections,
bool bTopologicalConnections,
ON_SimpleArray<ON_Mesh*>* components
) const
{
int i, j, k, kct, facecount = m_F.Count();
ON_SimpleArray<int> SortedFaceArray(facecount);
SortedFaceArray.SetCount(facecount);
int compct = GetConnectedComponents(bUseVertexConnections, bTopologicalConnections, SortedFaceArray);
if (0 == compct || 0 == components)
return compct;
bool bHasFaceNormals = HasFaceNormals();
bool bHasPrincipalCurvatures = HasPrincipalCurvatures();
bool bHasSurfaceParameters = HasSurfaceParameters();
bool bHasTextureCoordinates = HasTextureCoordinates();
bool bHasVertexColors = HasVertexColors();
bool bHasVertexNormals = HasVertexNormals();
ON_MeshFace newface;
newface.vi[0] = -1; newface.vi[1] = -1; newface.vi[2] = -1; newface.vi[3] = -1;
ON_SimpleArray<int> vertidxarray(m_V.Count());
vertidxarray.SetCount(m_V.Count());
const ON_3dPoint* pMesh_D = 0;
if ( HasDoublePrecisionVertices() )
{
if ( m_V.Count() > 0 && HasSynchronizedDoubleAndSinglePrecisionVertices() )
{
pMesh_D = DoublePrecisionVertices().Array();
}
}
ON_3dPointArray bogus_D;
for (i=1;compct>=i;i++)
{
kct = vertidxarray.Count();
for (k=0; kct>k; k++)
vertidxarray[k] = -1;
ON_Mesh* pNewMesh = new ON_Mesh();
if (0 == pNewMesh)
continue;
ON_3dPointArray& pNewMesh_D = ( 0 != pMesh_D )
? pNewMesh->DoublePrecisionVertices()
: bogus_D;
for (j=0;j<facecount;j++)
{
if ( i == SortedFaceArray[j] )
{
const ON_MeshFace& face = m_F[j];
kct = face.IsTriangle()?3:4;
for (k=0; k<kct; k++)
{
if (-1 != vertidxarray[face.vi[k]])
{
newface.vi[k] = vertidxarray[face.vi[k]];
continue;
}
int newvi;
if ( 0 != pMesh_D )
{
newvi = pNewMesh_D.Count();
pNewMesh_D.Append(pMesh_D[face.vi[k]]);
}
else
{
newvi = pNewMesh->m_V.Count();
pNewMesh->m_V.Append(m_V[face.vi[k]]);
}
newface.vi[k] = vertidxarray[face.vi[k]] = newvi;
if (true == bHasPrincipalCurvatures)
pNewMesh->m_K.Append(m_K[face.vi[k]]);
if (true == bHasSurfaceParameters)
pNewMesh->m_S.Append(m_S[face.vi[k]]);
if (true == bHasTextureCoordinates)
pNewMesh->m_T.Append(m_T[face.vi[k]]);
if (true == bHasVertexColors)
pNewMesh->m_C.Append(m_C[face.vi[k]]);
if (true == bHasVertexNormals)
pNewMesh->m_N.Append(m_N[face.vi[k]]);
}
if (3 == kct)
newface.vi[3] = newface.vi[2];
pNewMesh->m_F.Append(newface);
if (true == bHasFaceNormals)
pNewMesh->m_FN.Append(m_FN[j]);
}
}
if ( 0 != pMesh_D )
pNewMesh->UpdateSinglePrecisionVertices();
pNewMesh->Compact();
if (0 < pNewMesh->m_F.Count())
components->Append(pNewMesh);
else
{
delete pNewMesh;
pNewMesh = 0;
}
}
return compct;
}
