mapnik/plugins/input/ogr/ogr_converter.cpp

/*****************************************************************************
 * 
 * This file is part of Mapnik (c++ mapping toolkit)
 *
 * Copyright (C) 2011 Artem Pavlenko
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 *****************************************************************************/

// mapnik
#include <mapnik/global.hpp>
#include <mapnik/box2d.hpp>
#include <mapnik/geometry.hpp>
#include <mapnik/feature.hpp>
#include <mapnik/feature_layer_desc.hpp>
#include <mapnik/wkb.hpp>
#include <mapnik/unicode.hpp>

// ogr
#include "ogr_converter.hpp"

using mapnik::feature_ptr;
using mapnik::geometry_utils;
using mapnik::geometry_type;

void ogr_converter::convert_geometry(OGRGeometry* geom, feature_ptr feature, bool multiple_geometries)
{
    switch (wkbFlatten(geom->getGeometryType()))
    {
    case wkbPoint:
        convert_point(static_cast<OGRPoint*>(geom), feature);
        break;
    case wkbLineString:
        convert_linestring(static_cast<OGRLineString*>(geom), feature);
        break;
    case wkbPolygon:
        convert_polygon(static_cast<OGRPolygon*>(geom), feature);
        break;
    case wkbMultiPoint:
        if (multiple_geometries)
        {
            convert_multipoint_2(static_cast<OGRMultiPoint*>(geom), feature);
        }
        else
        {
            // Todo - using convert_multipoint_2 until we have proper multipoint handling in convert_multipoint
            // http://trac.mapnik.org/ticket/458
            //convert_multipoint(static_cast<OGRMultiPoint*>(geom), feature);
            convert_multipoint_2(static_cast<OGRMultiPoint*>(geom), feature);
        }
        break;
    case wkbMultiLineString:
        if (multiple_geometries)
        {
            convert_multilinestring_2(static_cast<OGRMultiLineString*>(geom), feature);
        }
        else
        {
            convert_multilinestring(static_cast<OGRMultiLineString*>(geom), feature);
        }
        break;
    case wkbMultiPolygon:
        if (multiple_geometries)
        {
            convert_multipolygon_2(static_cast<OGRMultiPolygon*>(geom), feature);
        }
        else
        {
            convert_multipolygon(static_cast<OGRMultiPolygon*>(geom), feature);
        }
        break;
    case wkbGeometryCollection:
        convert_collection(static_cast<OGRGeometryCollection*>(geom), feature, multiple_geometries);
        break;
    case wkbLinearRing:
        convert_linestring(static_cast<OGRLinearRing*>(geom), feature);
        break;
    case wkbNone:
    case wkbUnknown:
    default:
#ifdef MAPNIK_DEBUG
        std::clog << "OGR Plugin: unknown <ogr> geometry_type="
                  << wkbFlatten(geom->getGeometryType()) << std::endl;
#endif
        break;
    }
}

void ogr_converter::convert_point(OGRPoint* geom, feature_ptr feature)
{
    geometry_type * point = new geometry_type(mapnik::Point);
    point->move_to(geom->getX(), geom->getY());
    feature->add_geometry(point);
}

void ogr_converter::convert_linestring(OGRLineString* geom, feature_ptr feature)
{
    int num_points = geom->getNumPoints();
    geometry_type* line = new geometry_type(mapnik::LineString);
    line->set_capacity(num_points);
    line->move_to(geom->getX(0), geom->getY(0));
    for (int i = 1; i < num_points; ++i)
    {
        line->line_to (geom->getX(i), geom->getY(i));
    }
    feature->add_geometry(line);
}

void ogr_converter::convert_polygon(OGRPolygon* geom, feature_ptr feature)
{
    OGRLinearRing* exterior = geom->getExteriorRing();
    int num_points = exterior->getNumPoints();
    int num_interior = geom->getNumInteriorRings();
    int capacity = 0;
    for (int r = 0; r < num_interior; r++)
    {
        OGRLinearRing* interior = geom->getInteriorRing(r);
        capacity += interior->getNumPoints();
    }    
    geometry_type* poly = new geometry_type(mapnik::Polygon);
    poly->set_capacity(num_points + capacity);
    poly->move_to(exterior->getX(0), exterior->getY(0));
    for (int i = 1; i < num_points; ++i)
    {
        poly->line_to(exterior->getX(i), exterior->getY(i));
    }
    for (int r = 0; r < num_interior; r++)
    {
        OGRLinearRing* interior = geom->getInteriorRing(r);
        num_points = interior->getNumPoints();
        poly->move_to(interior->getX(0), interior->getY(0));
        for (int i = 1; i < num_points; ++i)
        {
            poly->line_to(interior->getX(i), interior->getY(i));
        }
    }
    feature->add_geometry(poly);
}

void ogr_converter::convert_multipoint(OGRMultiPoint* geom, feature_ptr feature)
{
    int num_geometries = geom->getNumGeometries();
    geometry_type* point = new geometry_type(mapnik::Point);
    
    for (int i = 0; i < num_geometries; i++)
    {
        OGRPoint* ogrpoint = static_cast<OGRPoint*>(geom->getGeometryRef(i));
        point->move_to(ogrpoint->getX(), ogrpoint->getY());
        //Todo - need to accept multiple points per mapnik::Point
    }
    
    // Todo - this only gets last point
    feature->add_geometry(point);
}

void ogr_converter::convert_multipoint_2(OGRMultiPoint* geom, feature_ptr feature)
{
    int num_geometries = geom->getNumGeometries();
    for (int i = 0; i < num_geometries; i++)
    {
        convert_point(static_cast<OGRPoint*>(geom->getGeometryRef(i)), feature);
    }
}

void ogr_converter::convert_multilinestring(OGRMultiLineString* geom, feature_ptr feature)
{
    int num_geometries = geom->getNumGeometries();

    int num_points = 0;
    for (int i = 0; i < num_geometries; i++)
    {
        OGRLineString* ls = static_cast<OGRLineString*>(geom->getGeometryRef(i));
        num_points += ls->getNumPoints();
    }

    geometry_type* line = new geometry_type(mapnik::LineString);
    line->set_capacity(num_points);
    
    for (int i = 0; i < num_geometries; i++)
    {
        OGRLineString* ls = static_cast<OGRLineString*>(geom->getGeometryRef(i));
        num_points = ls->getNumPoints();
        line->move_to(ls->getX(0), ls->getY(0));
        for (int i = 1; i < num_points; ++i)
        {
            line->line_to(ls->getX(i), ls->getY(i));
        }
    }

    feature->add_geometry(line);
}

void ogr_converter::convert_multilinestring_2(OGRMultiLineString* geom, feature_ptr feature)
{
    int num_geometries = geom->getNumGeometries();
    for (int i = 0; i < num_geometries; i++)
    {
        convert_linestring(static_cast<OGRLineString*>(geom->getGeometryRef(i)), feature);
    }
}

void ogr_converter::convert_multipolygon(OGRMultiPolygon* geom, feature_ptr feature)
{
    int num_geometries = geom->getNumGeometries();

    int capacity = 0;
    for (int i = 0; i < num_geometries; i++)
    {
        OGRPolygon* p = static_cast<OGRPolygon*>(geom->getGeometryRef(i));
        OGRLinearRing* exterior = p->getExteriorRing();
        capacity += exterior->getNumPoints();
        for (int r = 0; r < p->getNumInteriorRings(); r++)
        {
            OGRLinearRing* interior = p->getInteriorRing(r);
            capacity += interior->getNumPoints();
        }    
    }

    geometry_type* poly = new geometry_type(mapnik::Polygon);
    poly->set_capacity(capacity);

    for (int i = 0; i < num_geometries; i++)
    {
        OGRPolygon* p = static_cast<OGRPolygon*>(geom->getGeometryRef(i));
        OGRLinearRing* exterior = p->getExteriorRing();
        int num_points = exterior->getNumPoints();
        int num_interior = p->getNumInteriorRings();
        poly->move_to(exterior->getX(0), exterior->getY(0));
        for (int i = 1; i < num_points; ++i)
        {
            poly->line_to(exterior->getX(i), exterior->getY(i));
        }
        for (int r = 0; r < num_interior; r++)
        {
            OGRLinearRing* interior = p->getInteriorRing(r);
            num_points = interior->getNumPoints();
            poly->move_to(interior->getX(0), interior->getY(0));
            for (int i = 1; i < num_points; ++i)
            {
                poly->line_to(interior->getX(i), interior->getY(i));
            }
        }
    }

    feature->add_geometry(poly);
}

void ogr_converter::convert_multipolygon_2(OGRMultiPolygon* geom, feature_ptr feature)
{
    int num_geometries = geom->getNumGeometries();
    for (int i = 0; i < num_geometries; i++)
    {
        convert_polygon(static_cast<OGRPolygon*>(geom->getGeometryRef(i)), feature);
    }
}

void ogr_converter::convert_collection(OGRGeometryCollection* geom, feature_ptr feature, bool multiple_geometries)
{
    int num_geometries = geom->getNumGeometries();
    for (int i = 0; i < num_geometries; i++)
    {
        OGRGeometry* g = geom->getGeometryRef(i);
        if (g != NULL)
        {
            convert_geometry(g, feature, multiple_geometries);
        }
    }
}