DividerFilter.cpp

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#include "DividerFilter.hpp"

namespace pdal
{

static PluginInfo const s_info
{
    "filters.divider",
    "Divide points into approximately equal sized groups based on a simple "
      "scheme",
    "http://pdal.io/stages/filters.divider.html"
};

CREATE_STATIC_STAGE(DividerFilter, s_info)

std::string DividerFilter::getName() const { return s_info.name; }

std::istream& operator>>(std::istream& in, DividerFilter::Mode& mode)
{
    std::string s;
    in >> s;

    s = Utils::tolower(s);
    if (s == "round_robin")
        mode = DividerFilter::Mode::RoundRobin;
    else if (s == "partition")
        mode = DividerFilter::Mode::Partition;
    else
        throw pdal_error("filters.divider: Invalid 'mode' option '" + s + "'. "
            "Valid options are 'partition' and 'round_robin'");
    return in;
}


std::ostream& operator<<(std::ostream& out, const DividerFilter::Mode& mode)
{
    switch (mode)
    {
    case DividerFilter::Mode::RoundRobin:
        out << "round_robin";
    case DividerFilter::Mode::Partition:
        out << "partition";
    }
    return out;
}


void DividerFilter::addArgs(ProgramArgs& args)
{
    args.add("mode", "A mode of 'partition' will write sequential points "
        "to an output view until the view meets its predetermined size. "
        "'round_robin' mode will iterate through the output views as it "
        "writes sequential points.", m_mode, DividerFilter::Mode::Partition);
    m_cntArg = &args.add("count", "Number of output views", m_size);
    m_capArg = &args.add("capacity", "Maximum number of points in each "
        "output view", m_size);
}


void DividerFilter::initialize()
{
    if (m_cntArg->set() && m_capArg->set())
        throwError("Can't specify both option 'count' and option 'capacity.");
    if (!m_cntArg->set() && !m_capArg->set())
        throwError("Must specify either option 'count' or option 'capacity'.");
    if (m_cntArg->set())
    {
        m_sizeMode = SizeMode::Count;
        if (m_size < 2 || m_size > 1000)
            throwError("Option 'count' must be in the range [2, 1000].");
    }
    if (m_capArg->set())
        m_sizeMode = SizeMode::Capacity;
}


PointViewSet DividerFilter::run(PointViewPtr inView)
{
    if (m_sizeMode == SizeMode::Capacity)
        m_size = ((inView->size() - 1) / m_size) + 1;

    PointViewSet result;
    std::vector<PointViewPtr> views;
    for (point_count_t i = 0; i < m_size; ++i)
    {
        PointViewPtr v(inView->makeNew());
        views.push_back(v);
        result.insert(v);
    }

    if (m_mode == Mode::Partition)
    {
        point_count_t limit = ((inView->size() - 1) / m_size) + 1;
        unsigned viewNum = 0;
        for (PointId i = 0; i < inView->size();)
        {
            views[viewNum]->appendPoint(*inView, i++);
            if (i % limit == 0)
                viewNum++;
        }
    }
    else // RoundRobin
    {
        unsigned viewNum = 0;
        for (PointId i = 0; i < inView->size(); ++i)
        {
            views[viewNum]->appendPoint(*inView, i);
            viewNum++;
            if (viewNum == m_size)
                viewNum = 0;
        }
    }
    return result;
}

} // pdal