Function meshToDistanceVolume

source/MRVoxels/MRMeshToDistanceVolume.cpp:17–67

{

Expected<SimpleVolumeMinMax> meshToDistanceVolume( const MeshPart& mp, const MeshToDistanceVolumeParams& cParams /*= {} */ )
{
    MR_TIMER;
    if ( cParams.dist.signMode == SignDetectionMode::OpenVDB )
    {
        MeshToVolumeParams m2vPrams
        {
            .type = MeshToVolumeParams::Type::Signed,
            .voxelSize = cParams.vol.voxelSize,
            // SimpleVolume and VdbVolume are shifted on half voxel relative one another, see also VoxelsVolumeAccessor::shift()
            .worldXf = AffineXf3f::translation( -cParams.vol.origin - 0.5f * cParams.vol.voxelSize ),
            .cb = subprogress( cParams.vol.cb, 0.0f, 0.8f )
        };
        assert( cParams.dist.maxDistSq < FLT_MAX ); // the amount of work is proportional to maximal distance
        if ( cParams.dist.maxDistSq < FLT_MAX )
        {
            m2vPrams.surfaceOffset = std::sqrt( cParams.dist.maxDistSq )
                / std::min( { cParams.vol.voxelSize.x, cParams.vol.voxelSize.y, cParams.vol.voxelSize.z } );
        }
        return meshToDistanceVdbVolume( mp, m2vPrams ).and_then(
            [&cParams]( VdbVolume && vdbVolume )
            {
                return vdbVolumeToSimpleVolume( vdbVolume, Box3i{ Vector3i( 0, 0, 0 ), cParams.vol.dimensions }, subprogress( cParams.vol.cb, 0.8f, 1.0f ) );
            } );
    }

    auto params = cParams;
    if ( params.dist.signMode == SignDetectionMode::HoleWindingRule )
    {
        SimpleVolumeMinMax res;
        res.voxelSize = params.vol.voxelSize;
        res.dims = params.vol.dimensions;
        VolumeIndexer indexer( res.dims );
        res.data.resize( indexer.size() );

        if ( !params.fwn )
            params.fwn = std::make_shared<FastWindingNumber>( mp.mesh );
        assert( !mp.region ); // only whole mesh is supported for now
        auto basis = AffineXf3f( Matrix3f::scale( params.vol.voxelSize ), params.vol.origin + 0.5f * params.vol.voxelSize );
        if ( auto d = params.fwn->calcFromGridWithDistances( res.data.vec_, res.dims, basis, params.dist, params.vol.cb ); !d )
        {
            return unexpected( std::move( d.error() ) );
        }
        std::tie( res.min, res.max ) = parallelMinMax( res.data );
        return res;
    }

    const auto func = meshToDistanceFunctionVolume( mp, params );
    return functionVolumeToSimpleVolume( func, params.vol.cb );

}

FunctionVolume meshToDistanceFunctionVolume( const MeshPart& mp, const MeshToDistanceVolumeParams& params )
{