496 lines
12 KiB
C++
496 lines
12 KiB
C++
/*****************************************************************************
|
|
*
|
|
* This file is part of Mapnik (c++ mapping toolkit)
|
|
*
|
|
* Copyright (C) 2015 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/projection.hpp>
|
|
#include <mapnik/proj_transform.hpp>
|
|
#include <mapnik/coord.hpp>
|
|
|
|
#ifdef MAPNIK_USE_PROJ4
|
|
// proj4
|
|
#include <proj_api.h>
|
|
#endif
|
|
|
|
// stl
|
|
#include <vector>
|
|
#include <stdexcept>
|
|
|
|
namespace mapnik {
|
|
|
|
proj_transform::proj_transform(projection const& source,
|
|
projection const& dest)
|
|
: source_(source),
|
|
dest_(dest),
|
|
is_source_longlat_(false),
|
|
is_dest_longlat_(false),
|
|
is_source_equal_dest_(false),
|
|
wgs84_to_merc_(false),
|
|
merc_to_wgs84_(false)
|
|
{
|
|
is_source_equal_dest_ = (source_ == dest_);
|
|
if (!is_source_equal_dest_)
|
|
{
|
|
is_source_longlat_ = source_.is_geographic();
|
|
is_dest_longlat_ = dest_.is_geographic();
|
|
boost::optional<well_known_srs_e> src_k = source.well_known();
|
|
boost::optional<well_known_srs_e> dest_k = dest.well_known();
|
|
bool known_trans = false;
|
|
if (src_k && dest_k)
|
|
{
|
|
if (*src_k == WGS_84 && *dest_k == G_MERC)
|
|
{
|
|
wgs84_to_merc_ = true;
|
|
known_trans = true;
|
|
}
|
|
else if (*src_k == G_MERC && *dest_k == WGS_84)
|
|
{
|
|
merc_to_wgs84_ = true;
|
|
known_trans = true;
|
|
}
|
|
}
|
|
if (!known_trans)
|
|
{
|
|
#ifdef MAPNIK_USE_PROJ4
|
|
source_.init_proj4();
|
|
dest_.init_proj4();
|
|
#else
|
|
throw std::runtime_error(std::string("Cannot initialize proj_transform for given projections without proj4 support (-DMAPNIK_USE_PROJ4): '") + source_.params() + "'->'" + dest_.params() + "'");
|
|
#endif
|
|
}
|
|
}
|
|
}
|
|
|
|
bool proj_transform::equal() const
|
|
{
|
|
return is_source_equal_dest_;
|
|
}
|
|
|
|
bool proj_transform::is_known() const
|
|
{
|
|
return merc_to_wgs84_ || wgs84_to_merc_;
|
|
}
|
|
|
|
bool proj_transform::forward (double & x, double & y , double & z) const
|
|
{
|
|
return forward(&x, &y, &z, 1);
|
|
}
|
|
|
|
bool proj_transform::forward (geometry::point<double> & p) const
|
|
{
|
|
double z = 0;
|
|
return forward(&(p.x), &(p.y), &z, 1);
|
|
}
|
|
|
|
unsigned int proj_transform::forward (geometry::line_string<double> & ls) const
|
|
{
|
|
std::size_t size = ls.size();
|
|
if (size == 0) return 0;
|
|
|
|
if (is_source_equal_dest_)
|
|
return 0;
|
|
|
|
if (wgs84_to_merc_)
|
|
{
|
|
lonlat2merc(ls);
|
|
return 0;
|
|
}
|
|
else if (merc_to_wgs84_)
|
|
{
|
|
merc2lonlat(ls);
|
|
return 0;
|
|
}
|
|
|
|
geometry::point<double> * ptr = ls.data();
|
|
double * x = reinterpret_cast<double*>(ptr);
|
|
double * y = x + 1;
|
|
double * z = NULL;
|
|
if(!forward(x, y, z, size, 2))
|
|
{
|
|
return size;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
bool proj_transform::forward (double * x, double * y , double * z, int point_count, int offset) const
|
|
{
|
|
|
|
if (is_source_equal_dest_)
|
|
return true;
|
|
|
|
if (wgs84_to_merc_)
|
|
{
|
|
return lonlat2merc(x,y,point_count);
|
|
}
|
|
else if (merc_to_wgs84_)
|
|
{
|
|
return merc2lonlat(x,y,point_count);
|
|
}
|
|
|
|
#ifdef MAPNIK_USE_PROJ4
|
|
if (is_source_longlat_)
|
|
{
|
|
int i;
|
|
for(i=0; i<point_count; i++) {
|
|
x[i*offset] *= DEG_TO_RAD;
|
|
y[i*offset] *= DEG_TO_RAD;
|
|
}
|
|
}
|
|
|
|
if (pj_transform( source_.proj_, dest_.proj_, point_count,
|
|
offset, x,y,z) != 0)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
for(int j=0; j<point_count; j++) {
|
|
if (x[j] == HUGE_VAL || y[j] == HUGE_VAL)
|
|
{
|
|
return false;
|
|
}
|
|
}
|
|
|
|
if (is_dest_longlat_)
|
|
{
|
|
int i;
|
|
for(i=0; i<point_count; i++) {
|
|
x[i*offset] *= RAD_TO_DEG;
|
|
y[i*offset] *= RAD_TO_DEG;
|
|
}
|
|
}
|
|
#endif
|
|
return true;
|
|
}
|
|
|
|
bool proj_transform::backward (double * x, double * y , double * z, int point_count, int offset) const
|
|
{
|
|
if (is_source_equal_dest_)
|
|
return true;
|
|
|
|
if (wgs84_to_merc_)
|
|
{
|
|
return merc2lonlat(x,y,point_count);
|
|
}
|
|
else if (merc_to_wgs84_)
|
|
{
|
|
return lonlat2merc(x,y,point_count);
|
|
}
|
|
|
|
#ifdef MAPNIK_USE_PROJ4
|
|
if (is_dest_longlat_)
|
|
{
|
|
int i;
|
|
for(i=0; i<point_count; i++) {
|
|
x[i*offset] *= DEG_TO_RAD;
|
|
y[i*offset] *= DEG_TO_RAD;
|
|
}
|
|
}
|
|
|
|
if (pj_transform( dest_.proj_, source_.proj_, point_count,
|
|
offset, x,y,z) != 0)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
for(int j=0; j<point_count; j++) {
|
|
if (x[j] == HUGE_VAL || y[j] == HUGE_VAL)
|
|
{
|
|
return false;
|
|
}
|
|
}
|
|
|
|
if (is_source_longlat_)
|
|
{
|
|
int i;
|
|
for(i=0; i<point_count; i++) {
|
|
x[i*offset] *= RAD_TO_DEG;
|
|
y[i*offset] *= RAD_TO_DEG;
|
|
}
|
|
}
|
|
#endif
|
|
return true;
|
|
}
|
|
|
|
bool proj_transform::backward (double & x, double & y , double & z) const
|
|
{
|
|
return backward(&x, &y, &z, 1);
|
|
}
|
|
|
|
bool proj_transform::backward (geometry::point<double> & p) const
|
|
{
|
|
double z = 0;
|
|
return backward(&(p.x), &(p.y), &z, 1);
|
|
}
|
|
|
|
unsigned int proj_transform::backward (geometry::line_string<double> & ls) const
|
|
{
|
|
std::size_t size = ls.size();
|
|
if (size == 0) return 0;
|
|
|
|
if (is_source_equal_dest_)
|
|
return 0;
|
|
|
|
if (wgs84_to_merc_)
|
|
{
|
|
merc2lonlat(ls);
|
|
return 0;
|
|
}
|
|
else if (merc_to_wgs84_)
|
|
{
|
|
lonlat2merc(ls);
|
|
return 0;
|
|
}
|
|
|
|
geometry::point<double> * ptr = ls.data();
|
|
double * x = reinterpret_cast<double*>(ptr);
|
|
double * y = x + 1;
|
|
double * z = NULL;
|
|
if(!backward(x, y, z, size, 2))
|
|
{
|
|
return size;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
bool proj_transform::forward (box2d<double> & box) const
|
|
{
|
|
if (is_source_equal_dest_)
|
|
return true;
|
|
|
|
double llx = box.minx();
|
|
double ulx = box.minx();
|
|
double lly = box.miny();
|
|
double lry = box.miny();
|
|
double lrx = box.maxx();
|
|
double urx = box.maxx();
|
|
double uly = box.maxy();
|
|
double ury = box.maxy();
|
|
double z = 0.0;
|
|
if (!forward(llx,lly,z))
|
|
return false;
|
|
if (!forward(lrx,lry,z))
|
|
return false;
|
|
if (!forward(ulx,uly,z))
|
|
return false;
|
|
if (!forward(urx,ury,z))
|
|
return false;
|
|
|
|
double minx = std::min(ulx, llx);
|
|
double miny = std::min(lly, lry);
|
|
double maxx = std::max(urx, lrx);
|
|
double maxy = std::max(ury, uly);
|
|
box.init(minx,
|
|
miny,
|
|
maxx,
|
|
maxy);
|
|
return true;
|
|
}
|
|
|
|
bool proj_transform::backward (box2d<double> & box) const
|
|
{
|
|
if (is_source_equal_dest_)
|
|
return true;
|
|
|
|
double llx = box.minx();
|
|
double ulx = box.minx();
|
|
double lly = box.miny();
|
|
double lry = box.miny();
|
|
double lrx = box.maxx();
|
|
double urx = box.maxx();
|
|
double uly = box.maxy();
|
|
double ury = box.maxy();
|
|
double z = 0.0;
|
|
if (!backward(llx,lly,z))
|
|
return false;
|
|
if (!backward(lrx,lry,z))
|
|
return false;
|
|
if (!backward(ulx,uly,z))
|
|
return false;
|
|
if (!backward(urx,ury,z))
|
|
return false;
|
|
double minx = std::min(ulx, llx);
|
|
double miny = std::min(lly, lry);
|
|
double maxx = std::max(urx, lrx);
|
|
double maxy = std::max(ury, uly);
|
|
box.init(minx,
|
|
miny,
|
|
maxx,
|
|
maxy);
|
|
return true;
|
|
}
|
|
|
|
// Returns points in clockwise order. This allows us to do anti-meridian checks.
|
|
void envelope_points(std::vector< coord<double,2> > & coords, box2d<double>& env, int points)
|
|
{
|
|
double width = env.width();
|
|
double height = env.height();
|
|
|
|
int steps;
|
|
|
|
if (points <= 4) {
|
|
steps = 0;
|
|
} else {
|
|
steps = static_cast<int>(std::ceil((points - 4) / 4.0));
|
|
}
|
|
|
|
steps += 1;
|
|
double xstep = width / steps;
|
|
double ystep = height / steps;
|
|
|
|
coords.resize(points);
|
|
for (int i=0; i<steps; i++) {
|
|
// top: left>right
|
|
coords[i] = coord<double, 2>(env.minx() + i * xstep, env.maxy());
|
|
// right: top>bottom
|
|
coords[i + steps] = coord<double, 2>(env.maxx(), env.maxy() - i * ystep);
|
|
// bottom: right>left
|
|
coords[i + steps * 2] = coord<double, 2>(env.maxx() - i * xstep, env.miny());
|
|
// left: bottom>top
|
|
coords[i + steps * 3] = coord<double, 2>(env.minx(), env.miny() + i * ystep);
|
|
}
|
|
}
|
|
|
|
// determine if an ordered sequence of coordinates is in clockwise order
|
|
bool is_clockwise(const std::vector< coord<double,2> > & coords)
|
|
{
|
|
int n = coords.size();
|
|
coord<double,2> c1, c2;
|
|
double a = 0.0;
|
|
|
|
for (int i=0; i<n; i++) {
|
|
c1 = coords[i];
|
|
c2 = coords[(i + 1) % n];
|
|
a += (c1.x * c2.y - c2.x * c1.y);
|
|
}
|
|
return a <= 0.0;
|
|
}
|
|
|
|
box2d<double> calculate_bbox(std::vector<coord<double,2> > & points) {
|
|
std::vector<coord<double,2> >::iterator it = points.begin();
|
|
std::vector<coord<double,2> >::iterator it_end = points.end();
|
|
|
|
box2d<double> env(*it, *(++it));
|
|
for (; it!=it_end; ++it) {
|
|
env.expand_to_include(*it);
|
|
}
|
|
return env;
|
|
}
|
|
|
|
|
|
// More robust, but expensive, bbox transform
|
|
// in the face of proj4 out of bounds conditions.
|
|
// Can result in 20 -> 10 r/s performance hit.
|
|
// Alternative is to provide proper clipping box
|
|
// in the target srs by setting map 'maximum-extent'
|
|
|
|
bool proj_transform::backward(box2d<double>& env, int points) const
|
|
{
|
|
if (is_source_equal_dest_)
|
|
return true;
|
|
|
|
if (wgs84_to_merc_ || merc_to_wgs84_)
|
|
{
|
|
return backward(env);
|
|
}
|
|
|
|
std::vector<coord<double,2> > coords;
|
|
envelope_points(coords, env, points); // this is always clockwise
|
|
|
|
double z;
|
|
for (std::vector<coord<double,2> >::iterator it = coords.begin(); it!=coords.end(); ++it) {
|
|
z = 0;
|
|
if (!backward(it->x, it->y, z)) {
|
|
return false;
|
|
}
|
|
}
|
|
|
|
box2d<double> result = calculate_bbox(coords);
|
|
if (is_source_longlat_ && !is_clockwise(coords))
|
|
{
|
|
// we've gone to a geographic CS, and our clockwise envelope has
|
|
// changed into an anticlockwise one. This means we've crossed the antimeridian, and
|
|
// need to expand the X direction to +/-180 to include all the data. Once we can deal
|
|
// with multiple bboxes in queries we can improve.
|
|
double miny = result.miny();
|
|
result.expand_to_include(-180.0, miny);
|
|
result.expand_to_include(180.0, miny);
|
|
}
|
|
|
|
env.re_center(result.center().x, result.center().y);
|
|
env.height(result.height());
|
|
env.width(result.width());
|
|
|
|
return true;
|
|
}
|
|
|
|
bool proj_transform::forward(box2d<double>& env, int points) const
|
|
{
|
|
if (is_source_equal_dest_)
|
|
return true;
|
|
|
|
if (wgs84_to_merc_ || merc_to_wgs84_)
|
|
{
|
|
return forward(env);
|
|
}
|
|
|
|
std::vector<coord<double,2> > coords;
|
|
envelope_points(coords, env, points); // this is always clockwise
|
|
|
|
double z;
|
|
for (std::vector<coord<double,2> >::iterator it = coords.begin(); it!=coords.end(); ++it) {
|
|
z = 0;
|
|
if (!forward(it->x, it->y, z)) {
|
|
return false;
|
|
}
|
|
}
|
|
|
|
box2d<double> result = calculate_bbox(coords);
|
|
|
|
if (is_dest_longlat_ && !is_clockwise(coords))
|
|
{
|
|
// we've gone to a geographic CS, and our clockwise envelope has
|
|
// changed into an anticlockwise one. This means we've crossed the antimeridian, and
|
|
// need to expand the X direction to +/-180 to include all the data. Once we can deal
|
|
// with multiple bboxes in queries we can improve.
|
|
double miny = result.miny();
|
|
result.expand_to_include(-180.0, miny);
|
|
result.expand_to_include(180.0, miny);
|
|
}
|
|
|
|
env.re_center(result.center().x, result.center().y);
|
|
env.height(result.height());
|
|
env.width(result.width());
|
|
|
|
return true;
|
|
}
|
|
|
|
mapnik::projection const& proj_transform::source() const
|
|
{
|
|
return source_;
|
|
}
|
|
mapnik::projection const& proj_transform::dest() const
|
|
{
|
|
return dest_;
|
|
}
|
|
|
|
}
|