Function merge

source/MRMesh/MRObjectMesh.cpp:173–403

}

std::shared_ptr<ObjectMesh> merge( const std::vector<std::shared_ptr<ObjectMesh>>& objsMesh, const ObjectMeshMergeOptions& options )
{
    MR_TIMER;
    std::shared_ptr<ObjectMesh> res;
    const auto firstNotEmptyIt = std::find_if( objsMesh.begin(), objsMesh.end(), []( const auto & p ) { return p && p->mesh(); } );
    if ( firstNotEmptyIt == objsMesh.end() )
        return res; // if no input object, then no output
    res = std::make_shared<ObjectMesh>();
    res->copyAllSolidColors( **firstNotEmptyIt );

    bool hasVertColorMap = false;     // save if at least one has
    bool hasFaceColorMap = false;     // save if at least one has
    bool needSaveUVCoords = true;     // save if all have

    bool needSaveTextures = true;     // save if all have textures of same size
    bool exactSameTextures = true;    // true if all object has identical textures

    const Vector<MeshTexture, TextureId>* prevObjTextures = nullptr;


    size_t numTextures = 0;
    size_t totalVerts = 0;
    size_t totalFaces = 0;
    size_t numObject = 0;
    for ( const auto& obj : objsMesh )
    {
        if ( auto curMesh = obj->mesh() )
        {
            totalVerts += curMesh->topology.numValidVerts();
            totalFaces += curMesh->topology.numValidFaces();
            if ( !obj->getVertsColorMap().empty() )
                hasVertColorMap = true;
            if ( !obj->getFacesColorMap().empty() )
                hasFaceColorMap = true;
            if ( obj->getUVCoords().empty() )
                needSaveUVCoords = false;

            if ( !needSaveTextures )
                continue;

            const auto& textures = obj->getTextures();
            numTextures += textures.size();
            if ( textures.empty() )
            {
                needSaveTextures = false;
                continue;
            }
            if ( !prevObjTextures )
            {
                prevObjTextures = &textures;
                continue;
            }
            assert( prevObjTextures );
            if ( prevObjTextures->size() != textures.size() )
                exactSameTextures = false;
            if ( prevObjTextures->front().resolution != textures.front().resolution )
            {
                needSaveTextures = false;