mapnik/src/wkb.cpp
2021-01-05 14:39:07 +00:00

429 lines
13 KiB
C++

/*****************************************************************************
*
* This file is part of Mapnik (c++ mapping toolkit)
*
* Copyright (C) 2021 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/make_unique.hpp>
#include <mapnik/debug.hpp>
#include <mapnik/global.hpp>
#include <mapnik/wkb.hpp>
#include <mapnik/geometry.hpp>
#include <mapnik/util/noncopyable.hpp>
#include <mapnik/geometry/correct.hpp>
#include <memory>
namespace mapnik
{
struct wkb_reader : util::noncopyable
{
private:
const char* wkb_;
std::size_t size_;
std::size_t pos_;
wkbByteOrder byteOrder_;
bool needSwap_;
wkbFormat format_;
public:
enum wkbGeometryType {
wkbPoint=1,
wkbLineString=2,
wkbPolygon=3,
wkbMultiPoint=4,
wkbMultiLineString=5,
wkbMultiPolygon=6,
wkbGeometryCollection=7,
// Z
wkbPointZ=1001,
wkbLineStringZ=1002,
wkbPolygonZ=1003,
wkbMultiPointZ=1004,
wkbMultiLineStringZ=1005,
wkbMultiPolygonZ=1006,
wkbGeometryCollectionZ=1007,
// M
wkbPointM=2001,
wkbLineStringM=2002,
wkbPolygonM=2003,
wkbMultiPointM=2004,
wkbMultiLineStringM=2005,
wkbMultiPolygonM=2006,
wkbGeometryCollectionM=2007,
// ZM
wkbPointZM=3001,
wkbLineStringZM=3002,
wkbPolygonZM=3003,
wkbMultiPointZM=3004,
wkbMultiLineStringZM=3005,
wkbMultiPolygonZM=3006,
wkbGeometryCollectionZM=3007
};
wkb_reader(const char* wkb, std::size_t size, wkbFormat format)
: wkb_(wkb),
size_(size),
pos_(0),
format_(format)
{
// try to determine WKB format automatically
if (format_ == wkbAuto)
{
if (size_ >= 44
&& static_cast<unsigned char>(wkb_[0]) == static_cast<unsigned char>(0x00)
&& static_cast<unsigned char>(wkb_[38]) == static_cast<unsigned char>(0x7C)
&& static_cast<unsigned char>(wkb_[size_ - 1]) == static_cast<unsigned char>(0xFE))
{
format_ = wkbSpatiaLite;
}
else
{
format_ = wkbGeneric;
}
}
switch (format_)
{
case wkbSpatiaLite:
byteOrder_ = static_cast<wkbByteOrder>(wkb_[1]);
pos_ = 39;
break;
case wkbGeneric:
default:
byteOrder_ = static_cast<wkbByteOrder>(wkb_[0]);
pos_ = 1;
break;
}
needSwap_ = byteOrder_ ? wkbXDR : wkbNDR;
}
mapnik::geometry::geometry<double> read()
{
mapnik::geometry::geometry<double> geom = mapnik::geometry::geometry_empty();
int type = read_integer();
switch (type)
{
case wkbPoint:
{
auto pt = read_point();
if (!std::isnan(pt.x) && !std::isnan(pt.y))
geom = std::move(pt);
break;
}
case wkbLineString:
geom = read_linestring();
break;
case wkbPolygon:
geom = read_polygon();
break;
case wkbMultiPoint:
geom = read_multipoint();
break;
case wkbMultiLineString:
geom = read_multilinestring();
break;
case wkbMultiPolygon:
geom = read_multipolygon();
break;
case wkbGeometryCollection:
geom = read_collection();
break;
case wkbPointZ:
case wkbPointM:
{
auto pt = read_point<true>();
if (!std::isnan(pt.x) && !std::isnan(pt.y))
geom = std::move(pt);
break;
}
case wkbPointZM:
{
auto pt = read_point<true,true>();
if (!std::isnan(pt.x) && !std::isnan(pt.y))
geom = std::move(pt);
break;
}
case wkbLineStringZ:
case wkbLineStringM:
geom = read_linestring<true>();
break;
case wkbLineStringZM:
geom = read_linestring<true,true>();
break;
case wkbPolygonZ:
case wkbPolygonM:
geom = read_polygon<true>();
break;
case wkbPolygonZM:
geom = read_polygon<true,true>();
break;
case wkbMultiPointZ:
case wkbMultiPointM:
geom = read_multipoint<true>();
break;
case wkbMultiPointZM:
geom = read_multipoint<true,true>();
break;
case wkbMultiLineStringZ:
case wkbMultiLineStringM:
geom = read_multilinestring<true>();
break;
case wkbMultiLineStringZM:
geom = read_multilinestring<true,true>();
break;
case wkbMultiPolygonZ:
case wkbMultiPolygonM:
geom = read_multipolygon<true>();
break;
case wkbMultiPolygonZM:
geom = read_multipolygon<true,true>();
break;
case wkbGeometryCollectionZ:
case wkbGeometryCollectionM:
case wkbGeometryCollectionZM:
geom = read_collection();
break;
default:
break;
}
return geom;
}
private:
int read_integer()
{
std::int32_t n;
if (needSwap_)
{
read_int32_xdr(wkb_ + pos_, n);
}
else
{
read_int32_ndr(wkb_ + pos_, n);
}
pos_ += 4;
return n;
}
double read_double()
{
double d;
if (needSwap_)
{
read_double_xdr(wkb_ + pos_, d);
}
else
{
read_double_ndr(wkb_ + pos_, d);
}
pos_ += 8;
return d;
}
template <typename Ring, bool Z = false, bool M = false>
void read_coords(Ring & ring, std::size_t num_points)
{
double x,y;
if (!needSwap_)
{
for (std::size_t i = 0; i < num_points; ++i)
{
read_double_ndr(wkb_ + pos_, x);
read_double_ndr(wkb_ + pos_ + 8, y);
ring.emplace_back(x,y);
pos_ += 16; // skip XY
if (Z) pos_ += 8;
if (M) pos_ += 8;
}
}
else
{
for (std::size_t i = 0; i < num_points; ++i)
{
read_double_xdr(wkb_ + pos_, x);
read_double_xdr(wkb_ + pos_ + 8, y);
ring.emplace_back(x,y);
pos_ += 16; // skip XY
if (Z) pos_ += 8;
if (M) pos_ += 8;
}
}
}
template <bool Z = false, bool M = false>
mapnik::geometry::point<double> read_point()
{
double x = read_double();
double y = read_double();
if (Z) pos_ += 8;
if (M) pos_ += 8;
return mapnik::geometry::point<double>(x, y);
}
template <bool Z = false, bool M = false>
mapnik::geometry::multi_point<double> read_multipoint()
{
mapnik::geometry::multi_point<double> multi_point;
int num_points = read_integer();
multi_point.reserve(num_points);
for (int i = 0; i < num_points; ++i)
{
pos_ += 5;
multi_point.emplace_back(read_point<Z,M>());
}
return multi_point;
}
template <bool M = false, bool Z = false>
mapnik::geometry::line_string<double> read_linestring()
{
mapnik::geometry::line_string<double> line;
int num_points = read_integer();
if (num_points > 0)
{
line.reserve(num_points);
read_coords<mapnik::geometry::line_string<double>, M, Z>(line, num_points);
}
return line;
}
template <bool M = false, bool Z = false>
mapnik::geometry::multi_line_string<double> read_multilinestring()
{
int num_lines = read_integer();
mapnik::geometry::multi_line_string<double> multi_line;
multi_line.reserve(num_lines);
for (int i = 0; i < num_lines; ++i)
{
pos_ += 5;
multi_line.push_back(read_linestring<M, Z>());
}
return multi_line;
}
template <bool M = false, bool Z = false>
mapnik::geometry::polygon<double> read_polygon()
{
int num_rings = read_integer();
mapnik::geometry::polygon<double> poly;
poly.reserve(num_rings);
for (int i = 0; i < num_rings; ++i)
{
mapnik::geometry::linear_ring<double> ring;
int num_points = read_integer();
if (num_points > 0)
{
ring.reserve(num_points);
read_coords<mapnik::geometry::linear_ring<double>, M, Z>(ring, num_points);
}
poly.push_back(std::move(ring));
}
return poly;
}
template <bool M = false, bool Z = false>
mapnik::geometry::multi_polygon<double> read_multipolygon()
{
int num_polys = read_integer();
mapnik::geometry::multi_polygon<double> multi_poly;
multi_poly.reserve(num_polys);
for (int i = 0; i < num_polys; ++i)
{
pos_ += 5;
multi_poly.push_back(read_polygon<M, Z>());
}
return multi_poly;
}
mapnik::geometry::geometry_collection<double> read_collection()
{
int num_geometries = read_integer();
mapnik::geometry::geometry_collection<double> collection;
collection.reserve(num_geometries);
for (int i = 0; i < num_geometries; ++i)
{
pos_ += 1; // skip byte order
collection.push_back(read());
}
return collection;
}
std::string wkb_geometry_type_string(int type)
{
std::stringstream s;
switch (type)
{
case wkbPoint: s << "Point"; break;
case wkbPointZ: s << "PointZ"; break;
case wkbPointM: s << "PointM"; break;
case wkbPointZM: s << "PointZM"; break;
case wkbMultiPoint: s << "MultiPoint"; break;
case wkbMultiPointZ: s << "MultiPointZ"; break;
case wkbMultiPointM: s << "MultiPointM"; break;
case wkbMultiPointZM: s << "MultiPointZM"; break;
case wkbLineString: s << "LineString"; break;
case wkbLineStringZ: s << "LineStringZ"; break;
case wkbLineStringM: s << "LineStringM"; break;
case wkbLineStringZM: s << "LineStringZM"; break;
case wkbMultiLineString: s << "MultiLineString"; break;
case wkbMultiLineStringZ: s << "MultiLineStringZ"; break;
case wkbMultiLineStringM: s << "MultiLineStringM"; break;
case wkbMultiLineStringZM: s << "MultiLineStringZM"; break;
case wkbPolygon: s << "Polygon"; break;
case wkbPolygonZ: s << "PolygonZ"; break;
case wkbPolygonM: s << "PolygonM"; break;
case wkbPolygonZM: s << "PolygonZM"; break;
case wkbMultiPolygon: s << "MultiPolygon"; break;
case wkbMultiPolygonZ: s << "MultiPolygonZ"; break;
case wkbMultiPolygonM: s << "MultiPolygonM"; break;
case wkbMultiPolygonZM: s << "MultiPolygonZM"; break;
case wkbGeometryCollection: s << "GeometryCollection"; break;
case wkbGeometryCollectionZ: s << "GeometryCollectionZ"; break;
case wkbGeometryCollectionM: s << "GeometryCollectionM"; break;
case wkbGeometryCollectionZM:s << "GeometryCollectionZM"; break;
default: s << "wkbUnknown(" << type << ")"; break;
}
return s.str();
}
};
mapnik::geometry::geometry<double> geometry_utils::from_wkb(const char* wkb,
std::size_t size,
wkbFormat format)
{
wkb_reader reader(wkb, size, format);
mapnik::geometry::geometry<double> geom(reader.read());
// note: this will only be applied to polygons
mapnik::geometry::correct(geom);
return geom;
}
} // namespace mapnik