mapnik/include/mapnik/image_reader.hpp
2024-05-18 10:22:29 +02:00

77 lines
2.5 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
*
*****************************************************************************/
#ifndef MAPNIK_IMAGE_READER_HPP
#define MAPNIK_IMAGE_READER_HPP
// mapnik
#include <mapnik/image_any.hpp>
#include <mapnik/config.hpp>
#include <mapnik/util/noncopyable.hpp>
#include <mapnik/factory.hpp>
#include <mapnik/geometry/box2d.hpp>
// stl
#include <string>
#include <optional>
namespace mapnik {
class image_reader_exception : public std::exception
{
private:
std::string message_;
public:
image_reader_exception(std::string const& message)
: message_(message)
{}
~image_reader_exception() {}
virtual const char* what() const noexcept { return message_.c_str(); }
};
struct MAPNIK_DECL image_reader : private util::noncopyable
{
virtual unsigned width() const = 0;
virtual unsigned height() const = 0;
virtual bool has_alpha() const = 0;
virtual std::optional<box2d<double>> bounding_box() const = 0;
virtual void read(unsigned x, unsigned y, image_rgba8& image) = 0;
virtual image_any read(unsigned x, unsigned y, unsigned width, unsigned height) = 0;
virtual ~image_reader() {}
};
template<typename... Args>
bool register_image_reader(std::string const& type, image_reader* (*fun)(Args...))
{
return factory<image_reader, std::string, Args...>::instance().register_product(type, fun);
}
MAPNIK_DECL image_reader* get_image_reader(std::string const& file, std::string const& type);
MAPNIK_DECL image_reader* get_image_reader(std::string const& file);
MAPNIK_DECL image_reader* get_image_reader(char const* data, size_t size);
} // namespace mapnik
#endif // MAPNIK_IMAGE_READER_HPP