mapnik/plugins/input/tiles/raster_tiles_featureset.cpp

262 lines
9.7 KiB
C++

/*****************************************************************************
*
* This file is part of Mapnik (c++ mapping toolkit)
*
* Copyright (C) 2025 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/well_known_srs.hpp>
#include <mapnik/image_reader.hpp>
#include <mapnik/raster.hpp>
#include <mapnik/image.hpp>
#include <mapnik/view_transform.hpp>
#include <mapnik/feature_factory.hpp>
#include "raster_tiles_featureset.hpp"
#include "tiles_source.hpp"
// boost
#include <boost/format.hpp>
namespace {
inline mapnik::box2d<double> tile_envelope(int z, int x, int y)
{
int tile_count = 1 << z;
double x0 = x * (mapnik::EARTH_CIRCUMFERENCE / tile_count) - 0.5 * mapnik::EARTH_CIRCUMFERENCE;
double y0 = -y * (mapnik::EARTH_CIRCUMFERENCE / tile_count) + 0.5 * mapnik::EARTH_CIRCUMFERENCE;
double x1 = (x + 1) * (mapnik::EARTH_CIRCUMFERENCE / tile_count) - 0.5 * mapnik::EARTH_CIRCUMFERENCE;
double y1 = -(y + 1) * (mapnik::EARTH_CIRCUMFERENCE / tile_count) + 0.5 * mapnik::EARTH_CIRCUMFERENCE;
return mapnik::box2d<double>(x0, y0, x1, y1);
}
} // namespace
raster_tiles_featureset::raster_tiles_featureset(std::string const& tiles_location,
mapnik::context_ptr const& ctx,
mapnik::box2d<double> const& extent,
int zoom,
int xmin,
int xmax,
int ymin,
int ymax,
std::unordered_map<std::string, std::string>& tiles_cache,
std::size_t max_threads,
std::size_t datasource_hash,
double filter_factor)
: tiles_location_(tiles_location),
context_(ctx),
extent_(extent),
zoom_(zoom),
xmin_(xmin),
xmax_(xmax),
ymin_(ymin),
ymax_(ymax),
tiles_cache_(tiles_cache),
QUEUE_SIZE_((xmax - xmin + 1) * (ymax - ymin + 1)),
queue_(QUEUE_SIZE_),
stash_(ioc_, targets_, queue_),
max_threads_(max_threads),
datasource_hash_(datasource_hash),
filter_factor_(filter_factor)
{
try
{
boost::urls::url url = boost::urls::format(tiles_location_, {{"z", zoom_}, {"x", 0}, {"y", 0}});
host_ = url.host();
auto scheme = url.scheme();
if (scheme == "https")
{
ssl_ = true;
local_file_ = false;
port_ = url.port().empty() ? "443" : url.port();
}
else if (scheme == "http")
{
port_ = url.port().empty() ? "80" : url.port();
local_file_ = false;
}
}
catch (std::exception& ex)
{
std::cerr << ex.what() << std::endl;
}
}
raster_tiles_featureset::~raster_tiles_featureset()
{
for (std::size_t i = 0; i < workers_.size(); ++i)
{
workers_[i].join();
}
}
mapnik::feature_ptr raster_tiles_featureset::next_feature(std::string const& image_buffer,
int x,
int y,
std::string const& datasource_key)
{
std::unique_ptr<mapnik::image_reader> reader(mapnik::get_image_reader(image_buffer.c_str(), image_buffer.size()));
if (reader.get())
{
int image_width = reader->width();
int image_height = reader->height();
auto tile_bbox = tile_envelope(zoom_, x, y);
mapnik::view_transform t(image_width, image_height, tile_bbox, 0, 0);
mapnik::box2d<double> intersect = extent_.intersect(tile_bbox);
mapnik::box2d<double> ext = t.forward(intersect);
// select minimum raster containing whole ext
int x_off = static_cast<int>(std::floor(ext.minx()));
int y_off = static_cast<int>(std::floor(ext.miny()));
int end_x = static_cast<int>(std::ceil(ext.maxx()));
int end_y = static_cast<int>(std::ceil(ext.maxy()));
// clip to available data
if (x_off >= image_width)
x_off = image_width - 1;
if (y_off >= image_height)
y_off = image_height - 1;
if (x_off < 0)
x_off = 0;
if (y_off < 0)
y_off = 0;
if (end_x > image_width)
end_x = image_width;
if (end_y > image_height)
end_y = image_height;
int width = end_x - x_off;
int height = end_y - y_off;
if (width < 1)
width = 1;
if (height < 1)
height = 1;
mapnik::feature_ptr feature(
mapnik::feature_factory::create(context_, std::hash<std::string>{}(datasource_key)));
mapnik::image_any data = reader->read(x_off, y_off, width, height);
auto feature_raster_extent = t.backward(mapnik::box2d<double>(x_off, y_off, x_off + width, y_off + height));
mapnik::raster_ptr raster =
std::make_shared<mapnik::raster>(feature_raster_extent, intersect, std::move(data), filter_factor_);
feature->set_raster(raster);
return feature;
}
return mapnik::feature_ptr();
}
mapnik::feature_ptr raster_tiles_featureset::next()
{
if (first_)
{
first_ = false;
for (int x = xmin_; x <= xmax_; ++x)
{
for (int y = ymin_; y <= ymax_; ++y)
{
++num_tiles_;
auto datasource_key = (boost::format("%1%-%2%-%3%-%4%") % datasource_hash_ % zoom_ % x % y).str();
auto itr = tiles_cache_.find(datasource_key);
if (itr == tiles_cache_.end())
{
stash_.targets().emplace_back(zoom_, x, y);
}
else
{
std::string buffer = itr->second;
stash_.push_async(tile_data(zoom_, x, y));
}
}
}
std::size_t threads = std::min(max_threads_, stash_.targets().size());
workers_.reserve(threads + 1);
for (std::size_t i = 0; i < threads; ++i)
{
auto reporting_work =
boost::asio::require(ioc_.get_executor(), boost::asio::execution::outstanding_work.tracked);
if (local_file_)
{
workers_.emplace_back([this, reporting_work] {
std::unique_ptr<mapnik::tiles_source> source = mapnik::tiles_source::get_source(tiles_location_);
if (source)
{
while (!done_)
{
auto zxy = stash_.get_zxy();
if (!zxy)
break;
auto data = source->get_tile_raw(std::get<0>(*zxy), std::get<1>(*zxy), std::get<2>(*zxy));
stash_.push_async(
tile_data{std::get<0>(*zxy), std::get<1>(*zxy), std::get<2>(*zxy), std::move(data)});
}
}
});
}
#if defined(MAPNIK_HAS_OPENSSL)
else if (ssl_)
{
workers_.emplace_back([this, reporting_work] {
boost::asio::io_context ioc;
std::make_shared<worker_ssl>(ioc, ssl_ctx_, host_, port_, tiles_location_, stash_, std::ref(done_))
->run();
ioc.run();
});
}
#endif
else
{
workers_.emplace_back([this, reporting_work] {
boost::asio::io_context ioc;
std::make_shared<worker>(ioc, host_, port_, tiles_location_, stash_, std::ref(done_))->run();
ioc.run();
});
}
}
workers_.emplace_back([this] { ioc_.run(); });
}
// consume tiles from the queue
while (!done_.load())
{
tile_data tile;
if (queue_.pop(tile))
{
++consumed_count_;
auto datasource_key =
(boost::format("%1%-%2%-%3%-%4%") % datasource_hash_ % tile.zoom % tile.x % tile.y).str();
auto itr = tiles_cache_.find(datasource_key);
if (itr != tiles_cache_.end())
{
auto buffer = itr->second;
return next_feature(buffer, tile.x, tile.y, datasource_key);
}
else if (tile.data)
{
if ((*tile.data).empty())
{
continue;
}
tiles_cache_.emplace(datasource_key, *tile.data);
return next_feature(*tile.data, tile.x, tile.y, datasource_key);
}
}
if (consumed_count_ == num_tiles_)
done_.store(true);
}
return mapnik::feature_ptr();
}