Exemplo n.º 1
0
Imath::Box3d HoudiniScene::readBound( double time ) const
{
	OP_Node *node = retrieveNode( true );
	
	Imath::Box3d bounds;
	UT_BoundingBox box;
	OP_Context context( time );
	/// \todo: this doesn't account for SOPs containing multiple shapes
	/// if we fix it, we need to fix the condition below as well
	if ( node->getBoundingBox( box, context ) )
	{
		bounds = IECore::convert<Imath::Box3d>( box );
	}
	
	// paths embedded within a sop already have bounds accounted for
	if ( m_contentIndex )
	{
		return bounds;
	}
	
	NameList children;
	childNames( children );
	for ( NameList::iterator it=children.begin(); it != children.end(); ++it )
	{
		ConstSceneInterfacePtr childScene = child( *it );
		Imath::Box3d childBound = childScene->readBound( time );
		if ( !childBound.isEmpty() )
		{
			bounds.extendBy( Imath::transform( childBound, childScene->readTransformAsMatrix( time ) ) );
		}
	}
	
	return bounds;
}
Exemplo n.º 2
0
static Imath::Box3d getBoundingBox(const V3d& offset, const std::vector<float>& vertices)
{
    Imath::Box3d bbox;
    for (size_t i = 0; i < vertices.size(); i+=3)
        bbox.extendBy(V3d(vertices[i], vertices[i+1], vertices[i+2]));
    if (!bbox.isEmpty())
    {
        bbox.min += offset;
        bbox.max += offset;
    }
    return bbox;
}
Exemplo n.º 3
0
MBoundingBox convert( const Imath::Box3d &from )
{
	if( from.isEmpty() )
	{
		return MBoundingBox();
	}
	return MBoundingBox( convert<MPoint>( from.min ), convert<MPoint>( from.max ) );
}
Exemplo n.º 4
0
Imath::Box3d LiveScene::readBound( double time ) const
{
	tbb::mutex::scoped_lock l( s_mutex );
	
	if( fabs( MAnimControl::currentTime().as( MTime::kSeconds ) - time ) > 1.e-4 )
	{
		throw Exception( "IECoreMaya::LiveScene::readBound: time must be the same as on the maya timeline!" );
	}
	
	if( m_isRoot )
	{
		MDagPathArray paths;
		getChildDags( m_dagPath, paths );
		
		Imath::Box3d bound;
		
		for( unsigned i=0; i < paths.length(); ++i )
		{
			MFnDagNode dagFn( paths[i] );
			Imath::Box3d b = IECore::convert<Imath::Box3d, MBoundingBox>( dagFn.boundingBox() );
			
			if( b.hasVolume() )
			{
				bound.extendBy( b );
			}
		}
		
		return bound;
	}
	else if( m_dagPath.length() == 0 )
	{
		throw Exception( "IECoreMaya::LiveScene::readBound: Dag path no longer exists!" );
	}
	else
	{
		MFnDagNode dagFn( m_dagPath );
		Imath::Box3d ret = IECore::convert<Imath::Box3d, MBoundingBox>( dagFn.boundingBox() );
		Imath::M44d invTransform = IECore::convert<Imath::M44d, MMatrix>( dagFn.transformationMatrix() ).inverse();
		return Imath::transform( ret, invTransform );
	}
}
Exemplo n.º 5
0
/// Load point cloud in text format, assuming fields XYZ
bool PointArray::loadText(QString fileName, size_t maxPointCount,
                          std::vector<GeomField>& fields, V3d& offset,
                          size_t& npoints, uint64_t& totPoints,
                          Imath::Box3d& bbox, V3d& centroid)
{
    V3d Psum(0);
    // Use C file IO here, since it's about 40% faster than C++ streams for
    // large text files (tested on linux x86_64, gcc 4.6.3).
    FILE* inFile = fopen(fileName.toUtf8(), "r");
    if (!inFile)
        return false;
    fseek(inFile, 0, SEEK_END);
    const size_t numBytes = ftell(inFile);
    fseek(inFile, 0, SEEK_SET);
    std::vector<Imath::V3d> points;
    Imath::V3d p;
    size_t readCount = 0;
    // Read three doubles; "%*[^\n]" discards up to just before end of line
    while (fscanf(inFile, " %lf %lf %lf%*[^\n]", &p.x, &p.y, &p.z) == 3)
    {
        points.push_back(p);
        ++readCount;
        if (readCount % 10000 == 0)
            emit loadProgress(int(100*ftell(inFile)/numBytes));
    }
    fclose(inFile);
    totPoints = points.size();
    npoints = points.size();
    // Zero points + nonzero bytes => bad text file
    if (totPoints == 0 && numBytes != 0)
        return false;
    if (totPoints > 0)
        offset = points[0];
    fields.push_back(GeomField(TypeSpec::vec3float32(), "position", npoints));
    V3f* position = (V3f*)fields[0].as<float>();
    for (size_t i = 0; i < npoints; ++i)
    {
        position[i] = points[i] - offset;
        bbox.extendBy(points[i]);
        Psum += points[i];
    }
    if (npoints > 0)
        centroid = (1.0/npoints)*Psum;
    return true;
}
Exemplo n.º 6
0
/// Load ascii version of the point cloud library PCD format
bool PointArray::loadPly(QString fileName, size_t maxPointCount,
                         std::vector<GeomField>& fields, V3d& offset,
                         size_t& npoints, uint64_t& totPoints,
                         Imath::Box3d& bbox, V3d& centroid)
{
    std::unique_ptr<t_ply_, int(*)(p_ply)> ply(
            ply_open(fileName.toUtf8().constData(), NULL, 0, NULL), ply_close);
    if (!ply || !ply_read_header(ply.get()))
        return false;
    // Parse out header data
    p_ply_element vertexElement = findVertexElement(ply.get(), npoints);
    if (vertexElement)
    {
        if (!loadPlyVertexProperties(fileName, ply.get(), vertexElement, fields, offset, npoints))
            return false;
    }
    else
    {
        if (!loadDisplazNativePly(fileName, ply.get(), fields, offset, npoints))
            return false;
    }
    totPoints = npoints;

    // Compute bounding box and centroid
    const V3f* P = (V3f*)fields[0].as<float>();
    V3d Psum(0);
    for (size_t i = 0; i < npoints; ++i)
    {
        Psum += P[i];
        bbox.extendBy(P[i]);
    }
    if (npoints > 0)
        centroid = (1.0/npoints) * Psum;
    centroid += offset;
    bbox.min += offset;
    bbox.max += offset;
    return true;
}
Exemplo n.º 7
0
bool PointArray::loadFile(QString fileName, size_t maxPointCount)
{
    QTime loadTimer;
    loadTimer.start();
    setFileName(fileName);
    // Read file into point data fields.  Use very basic file type detection
    // based on extension.
    uint64_t totPoints = 0;
    Imath::Box3d bbox;
    V3d offset(0);
    V3d centroid(0);
    emit loadStepStarted("Reading file");
    if (fileName.endsWith(".las") || fileName.endsWith(".laz"))
    {
        if (!loadLas(fileName, maxPointCount, m_fields, offset,
                     m_npoints, totPoints, bbox, centroid))
        {
            return false;
        }
    }
    else if (fileName.endsWith(".ply"))
    {
        if (!loadPly(fileName, maxPointCount, m_fields, offset,
                     m_npoints, totPoints, bbox, centroid))
        {
            return false;
        }
    }
#if 0
    else if (fileName.endsWith(".dat"))
    {
        // Load crappy db format for debugging
        std::ifstream file(fileName.toUtf8(), std::ios::binary);
        file.seekg(0, std::ios::end);
        totPoints = file.tellg()/(4*sizeof(float));
        file.seekg(0);
        m_fields.push_back(GeomField(TypeSpec::vec3float32(), "position", totPoints));
        m_fields.push_back(GeomField(TypeSpec::float32(), "intensity", totPoints));
        float* position = m_fields[0].as<float>();
        float* intensity = m_fields[1].as<float>();
        for (size_t i = 0; i < totPoints; ++i)
        {
            file.read((char*)position, 3*sizeof(float));
            file.read((char*)intensity, 1*sizeof(float));
            bbox.extendBy(V3d(position[0], position[1], position[2]));
            position += 3;
            intensity += 1;
        }
        m_npoints = totPoints;
    }
#endif
    else
    {
        // Last resort: try loading as text
        if (!loadText(fileName, maxPointCount, m_fields, offset,
                      m_npoints, totPoints, bbox, centroid))
        {
            return false;
        }
    }
    // Search for position field
    m_positionFieldIdx = -1;
    for (size_t i = 0; i < m_fields.size(); ++i)
    {
        if (m_fields[i].name == "position" && m_fields[i].spec.count == 3)
        {
            m_positionFieldIdx = (int)i;
            break;
        }
    }
    if (m_positionFieldIdx == -1)
    {
        g_logger.error("No position field found in file %s", fileName);
        return false;
    }
    m_P = (V3f*)m_fields[m_positionFieldIdx].as<float>();
    setBoundingBox(bbox);
    setOffset(offset);
    setCentroid(centroid);
    emit loadProgress(100);
    g_logger.info("Loaded %d of %d points from file %s in %.2f seconds",
                  m_npoints, totPoints, fileName, loadTimer.elapsed()/1000.0);
    if (totPoints == 0)
    {
        m_rootNode.reset(new OctreeNode(V3f(0), 1));
        return true;
    }

    // Sort points into octree order
    emit loadStepStarted("Sorting points");
    std::unique_ptr<size_t[]> inds(new size_t[m_npoints]);
    for (size_t i = 0; i < m_npoints; ++i)
        inds[i] = i;
    // Expand the bound so that it's cubic.  Not exactly sure it's required
    // here, but cubic nodes sometimes work better the points are better
    // distributed for LoD, splitting is unbiased, etc.
    Imath::Box3f rootBound(bbox.min - offset, bbox.max - offset);
    V3f diag = rootBound.size();
    float rootRadius = std::max(std::max(diag.x, diag.y), diag.z) / 2;
    ProgressFunc progressFunc(*this);
    m_rootNode.reset(makeTree(0, &inds[0], 0, m_npoints, &m_P[0],
                              rootBound.center(), rootRadius, progressFunc));
    // Reorder point fields into octree order
    emit loadStepStarted("Reordering fields");
    for (size_t i = 0; i < m_fields.size(); ++i)
    {
        g_logger.debug("Reordering field %d: %s", i, m_fields[i]);
        reorder(m_fields[i], inds.get(), m_npoints);
        emit loadProgress(int(100*(i+1)/m_fields.size()));
    }
    m_P = (V3f*)m_fields[m_positionFieldIdx].as<float>();

    return true;
}
Exemplo n.º 8
0
// Triangulate a polygon, returning vertex indices to the triangles
//
// verts - 3D vertex positions
// outerRingInds  - Indices of outer boundary vertices in `verts` array;
//                  the j'th component of the i'th polygon vertex is
//                  verts[3*outerRingInds[i]+j].
// innerRingSizes - Number of vertices in each polygon hole
// innerRingInds  - Indices of vertices for all holes; the first hole has
//                  indices innerRingInds[i] for i in [0, innerRingSize[0])
// triangleInds   - Indices of triangular pieces are appended to this array.
//
// Return false if polygon couldn't be triangulated.
static bool triangulatePolygon(const std::vector<float>& verts,
                               const std::vector<GLuint>& outerRingInds,
                               const std::vector<GLuint>& innerRingSizes,
                               const std::vector<GLuint>& innerRingInds,
                               std::vector<GLuint>& triangleInds)
{
    // Figure out which dimension the bounding box is smallest along, and
    // discard it to reduce dimensionality to 2D.
    Imath::Box3d bbox;
    for (size_t i = 0; i < outerRingInds.size(); ++i)
    {
        GLuint j = 3*outerRingInds[i];
        assert(j + 2 < verts.size());
        bbox.extendBy(V3d(verts[j], verts[j+1], verts[j+2]));
    }
    V3d diag = bbox.size();
    int xind = 0;
    int yind = 1;
    if (diag.z > std::min(diag.x, diag.y))
    {
        if (diag.x < diag.y)
            xind = 2;
        else
            yind = 2;
    }
    std::list<TPPLPoly> triangles;
    if (innerRingSizes.empty())
    {
        TPPLPoly poly;
        // Simple case - no holes
        //
        // TODO: Use Triangulate_MONO, after figuring out why it's not always
        // working?
        initTPPLPoly(poly, verts, xind, yind,
                     outerRingInds.data(), (int)outerRingInds.size(), false);
        TPPLPartition polypartition;
        if (!polypartition.Triangulate_EC(&poly, &triangles))
        {
            g_logger.warning("Ignoring polygon which couldn't be triangulated.");
            return false;
        }
    }
    else
    {
        // Set up outer polygon boundary and holes.
        std::list<TPPLPoly> inputPolys;
        inputPolys.resize(1 + innerRingSizes.size());
        auto polyIter = inputPolys.begin();
        initTPPLPoly(*polyIter, verts, xind, yind,
                     outerRingInds.data(), (int)outerRingInds.size(), false);
        ++polyIter;
        for (size_t i = 0, j = 0; i < innerRingSizes.size(); ++i, ++polyIter)
        {
            size_t count = innerRingSizes[i];
            if (j + count > innerRingInds.size())
            {
                g_logger.warning("Ignoring polygon with inner ring %d of %d too large",
                                 i, innerRingSizes.size());
                return false;
            }
            initTPPLPoly(*polyIter, verts, xind, yind,
                         innerRingInds.data() + j, (int)count, true);
            j += count;
        }
        // Triangulate
        std::list<TPPLPoly> noHolePolys;
        TPPLPartition polypartition;
        polypartition.RemoveHoles(&inputPolys, &noHolePolys);
        if (!polypartition.Triangulate_EC(&noHolePolys, &triangles))
        {
            g_logger.warning("Ignoring polygon which couldn't be triangulated.");
            return false;
        }
    }
    for (auto tri = triangles.begin(); tri != triangles.end(); ++tri)
    {
        triangleInds.push_back((*tri)[0].id);
        triangleInds.push_back((*tri)[1].id);
        triangleInds.push_back((*tri)[2].id);
    }
    return true;
}
Exemplo n.º 9
0
bool PointArray::loadLas(QString fileName, size_t maxPointCount,
                         std::vector<GeomField>& fields, V3d& offset,
                         size_t& npoints, uint64_t& totalPoints,
                         Imath::Box3d& bbox, V3d& centroid)
{
    V3d Psum(0);
#ifdef DISPLAZ_USE_PDAL
    // Open file
    if (!pdal::FileUtils::fileExists(fileName.toLatin1().constData()))
    {
        g_logger.info("File \"%s\" does not exist", fileName.toStdString() );
        return false;
    }
    std::unique_ptr<pdal::PipelineManager> manager(new pdal::PipelineManager);

    pdal::StageFactory factory;
    std::string driver = factory.inferReaderDriver(fileName.toStdString());
    manager->addReader(driver);

    pdal::Stage* reader = static_cast<pdal::Reader*>(manager->getStage());
    pdal::Options options;
    pdal::Option fname("filename", fileName.toStdString());
    options.add(fname);
    reader->setOptions(options);

    manager->execute();
    pdal::PointBufferSet pbSet = manager->buffers();

    pdal::PointContext context = manager->context();
    bool hasColor = context.hasDim(pdal::Dimension::Id::Red);
    pdal::QuickInfo quickinfo = reader->preview();

    // Figure out how much to decimate the point cloud.
    totalPoints = quickinfo.m_pointCount;
    size_t decimate = totalPoints == 0 ? 1 : 1 + (totalPoints - 1) / maxPointCount;
    if(decimate > 1)
    {
        g_logger.info("Decimating \"%s\" by factor of %d",
                      fileName.toStdString(), decimate);
    }
    npoints = (totalPoints + decimate - 1) / decimate;
    pdal::BOX3D pdal_bounds = quickinfo.m_bounds;
    offset = V3d(0.5*(pdal_bounds.minx + pdal_bounds.maxx),
                 0.5*(pdal_bounds.miny + pdal_bounds.maxy),
                 0.5*(pdal_bounds.minz + pdal_bounds.maxz));
    // Attempt to place all data on the same vertical scale, but allow
    // other offsets if the magnitude of z is too large (and we would
    // therefore loose noticable precision by storing the data as floats)
    if (fabs(offset.z) < 10000)
        offset.z = 0;
    // Allocate all arrays
    fields.push_back(GeomField(TypeSpec::vec3float32(), "position", npoints));
    fields.push_back(GeomField(TypeSpec::uint16_i(), "intensity", npoints));
    fields.push_back(GeomField(TypeSpec::uint8_i(), "returnNumber", npoints));
    fields.push_back(GeomField(TypeSpec::uint8_i(), "numberOfReturns", npoints));
    fields.push_back(GeomField(TypeSpec::uint8_i(), "pointSourceId", npoints));
    fields.push_back(GeomField(TypeSpec::uint8_i(), "classification", npoints));
    // Output iterators for the output arrays
    V3f* position           = (V3f*)fields[0].as<float>();
    uint16_t* intensity     = fields[1].as<uint16_t>();
    uint8_t* returnNumber   = fields[2].as<uint8_t>();
    uint8_t* numReturns     = fields[3].as<uint8_t>();
    uint8_t* pointSourceId  = fields[4].as<uint8_t>();
    uint8_t* classification = fields[5].as<uint8_t>();
    uint16_t* color = 0;
    if (hasColor)
    {
        fields.push_back(GeomField(TypeSpec(TypeSpec::Uint,2,3,TypeSpec::Color),
                                        "color", npoints));
        color = fields.back().as<uint16_t>();
    }
    size_t readCount = 0;
    size_t storeCount = 0;
    size_t nextDecimateBlock = 1;
    size_t nextStore = 1;
    for (auto st = pbSet.begin(); st != pbSet.end(); ++st)
//     while (size_t numRead = chunkIter->read(buf))
    {
        pdal::PointBufferPtr buf = *st;
        for (size_t i = 0; i < buf->size(); ++i)
        {
            ++readCount;
            V3d P = V3d(buf->getFieldAs<double>(pdal::Dimension::Id::X, i),
                        buf->getFieldAs<double>(pdal::Dimension::Id::Y, i),
                        buf->getFieldAs<double>(pdal::Dimension::Id::Z, i));
//             V3d P = V3d(xDim.applyScaling(buf.getField<int32_t>(xDim, i)),
//                         yDim.applyScaling(buf.getField<int32_t>(yDim, i)),
//                         zDim.applyScaling(buf.getField<int32_t>(zDim, i)));
            bbox.extendBy(P);
            Psum += P;
            if(readCount < nextStore)
                continue;
            ++storeCount;
            // Store the point
            *position++ = P - offset;
            *intensity++   = buf->getFieldAs<uint16_t>(pdal::Dimension::Id::Intensity, i);
            *returnNumber++ = buf->getFieldAs<uint8_t>(pdal::Dimension::Id::ReturnNumber, i);
            *numReturns++  = buf->getFieldAs<uint8_t>(pdal::Dimension::Id::NumberOfReturns, i);
            *pointSourceId++ = buf->getFieldAs<uint8_t>(pdal::Dimension::Id::PointSourceId, i);
            *classification++ = buf->getFieldAs<uint8_t>(pdal::Dimension::Id::Classification, i);
            // Extract point RGB
            if (hasColor)
            {
                *color++ = buf->getFieldAs<uint16_t>(pdal::Dimension::Id::Red, i);
                *color++ = buf->getFieldAs<uint16_t>(pdal::Dimension::Id::Green, i);
                *color++ = buf->getFieldAs<uint16_t>(pdal::Dimension::Id::Blue, i);
            }
            // Figure out which point will be the next stored point.
            nextDecimateBlock += decimate;
            nextStore = nextDecimateBlock;
            if(decimate > 1)
            {
                // Randomize selected point within block to avoid repeated patterns
                nextStore += (qrand() % decimate);
                if(nextDecimateBlock <= totalPoints && nextStore > totalPoints)
                    nextStore = totalPoints;
            }
        }
        emit loadProgress(100*readCount/totalPoints);
    }
#else
    LASreadOpener lasReadOpener;
#ifdef _WIN32
    // Hack: liblas doesn't like forward slashes as path separators on windows
    fileName = fileName.replace('/', '\\');
#endif
    lasReadOpener.set_file_name(fileName.toLatin1().constData());
    std::unique_ptr<LASreader> lasReader(lasReadOpener.open());

    if(!lasReader)
    {
        g_logger.error("Couldn't open file \"%s\"", fileName);
        return false;
    }

    //std::ofstream dumpFile("points.txt");
    // Figure out how much to decimate the point cloud.
    totalPoints = std::max<uint64_t>(lasReader->header.extended_number_of_point_records,
                                   lasReader->header.number_of_point_records);
    size_t decimate = totalPoints == 0 ? 1 : 1 + (totalPoints - 1) / maxPointCount;
    if(decimate > 1)
    {
        g_logger.info("Decimating \"%s\" by factor of %d",
                        fileName.toStdString(), decimate);
    }
    npoints = (totalPoints + decimate - 1) / decimate;
    offset = V3d(lasReader->header.min_x, lasReader->header.min_y, 0);
    // Attempt to place all data on the same vertical scale, but allow other
    // offsets if the magnitude of z is too large (and we would therefore loose
    // noticable precision by storing the data as floats)
    if (fabs(lasReader->header.min_z) > 10000)
        offset.z = lasReader->header.min_z;
    fields.push_back(GeomField(TypeSpec::vec3float32(), "position", npoints));
    fields.push_back(GeomField(TypeSpec::uint16_i(), "intensity", npoints));
    fields.push_back(GeomField(TypeSpec::uint8_i(), "returnNumber", npoints));
    fields.push_back(GeomField(TypeSpec::uint8_i(), "numberOfReturns", npoints));
    fields.push_back(GeomField(TypeSpec::uint8_i(), "pointSourceId", npoints));
    fields.push_back(GeomField(TypeSpec::uint8_i(), "classification", npoints));
    if (totalPoints == 0)
    {
        g_logger.warning("File %s has zero points", fileName);
        return true;
    }
    // Iterate over all points & pull in the data.
    V3f* position           = (V3f*)fields[0].as<float>();
    uint16_t* intensity     = fields[1].as<uint16_t>();
    uint8_t* returnNumber   = fields[2].as<uint8_t>();
    uint8_t* numReturns     = fields[3].as<uint8_t>();
    uint8_t* pointSourceId  = fields[4].as<uint8_t>();
    uint8_t* classification = fields[5].as<uint8_t>();
    uint64_t readCount = 0;
    uint64_t nextDecimateBlock = 1;
    uint64_t nextStore = 1;
    size_t storeCount = 0;
    if (!lasReader->read_point())
        return false;
    const LASpoint& point = lasReader->point;
    uint16_t* color = 0;
    if (point.have_rgb)
    {
        fields.push_back(GeomField(TypeSpec(TypeSpec::Uint,2,3,TypeSpec::Color),
                                   "color", npoints));
        color = fields.back().as<uint16_t>();
    }
    do
    {
        // Read a point from the las file
        ++readCount;
        if(readCount % 10000 == 0)
            emit loadProgress(100*readCount/totalPoints);
        V3d P = V3d(point.get_x(), point.get_y(), point.get_z());
        bbox.extendBy(P);
        Psum += P;
        if(readCount < nextStore)
            continue;
        ++storeCount;
        // Store the point
        *position++ = P - offset;
        // float intens = float(point.scan_angle_rank) / 40;
        *intensity++ = point.intensity;
        *returnNumber++ = point.return_number;
#       if LAS_TOOLS_VERSION >= 140315
        *numReturns++ = point.number_of_returns;
#       else
        *numReturns++ = point.number_of_returns_of_given_pulse;
#       endif
        *pointSourceId++ = point.point_source_ID;
        // Put flags back in classification byte to avoid memory bloat
        *classification++ = point.classification | (point.synthetic_flag << 5) |
                            (point.keypoint_flag << 6) | (point.withheld_flag << 7);
        // Extract point RGB
        if (color)
        {
            *color++ = point.rgb[0];
            *color++ = point.rgb[1];
            *color++ = point.rgb[2];
        }
        // Figure out which point will be the next stored point.
        nextDecimateBlock += decimate;
        nextStore = nextDecimateBlock;
        if(decimate > 1)
        {
            // Randomize selected point within block to avoid repeated patterns
            nextStore += (qrand() % decimate);
            if(nextDecimateBlock <= totalPoints && nextStore > totalPoints)
                nextStore = totalPoints;
        }
    }
    while(lasReader->read_point());
    lasReader->close();
#endif
    if (readCount < totalPoints)
    {
        g_logger.warning("Expected %d points in file \"%s\", got %d",
                         totalPoints, fileName, readCount);
        npoints = storeCount;
        // Shrink all fields to fit - these will have wasted space at the end,
        // but that will be fixed during reordering.
        for (size_t i = 0; i < fields.size(); ++i)
            fields[i].size = npoints;
        totalPoints = readCount;
    }
    if (totalPoints > 0)
        centroid = (1.0/totalPoints)*Psum;
    return true;
}