mapnik/src/color.cpp
2014-01-26 14:00:58 -08:00

108 lines
3.5 KiB
C++

/*****************************************************************************
*
* 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/color.hpp>
#include <mapnik/color_factory.hpp>
#include <mapnik/config_error.hpp>
// agg
#include "agg_color_rgba.h"
// boost
#include <boost/spirit/include/karma.hpp>
#include <boost/spirit/include/phoenix_statement.hpp>
// stl
#include <sstream>
namespace mapnik {
color::color(std::string const& str)
{
*this = parse_color(str);
}
std::string color::to_string() const
{
namespace karma = boost::spirit::karma;
boost::spirit::karma::_1_type _1;
boost::spirit::karma::eps_type eps;
boost::spirit::karma::double_type double_;
boost::spirit::karma::string_type kstring;
boost::spirit::karma::uint_generator<uint8_t,10> color_generator;
std::string str;
std::back_insert_iterator<std::string> sink(str);
karma::generate(sink,
// begin grammar
kstring[ phoenix::if_(alpha()==255) [_1="rgb("].else_[_1="rgba("]]
<< color_generator[_1 = red()] << ','
<< color_generator[_1 = green()] << ','
<< color_generator[_1 = blue()]
<< kstring[ phoenix::if_(alpha()==255) [_1 = ')'].else_[_1 =',']]
<< eps(alpha()<255) << double_ [_1 = alpha()/255.0]
<< ')'
// end grammar
);
return str;
}
std::string color::to_hex_string() const
{
namespace karma = boost::spirit::karma;
boost::spirit::karma::_1_type _1;
boost::spirit::karma::hex_type hex;
boost::spirit::karma::eps_type eps;
boost::spirit::karma::right_align_type right_align;
std::string str;
std::back_insert_iterator<std::string> sink(str);
karma::generate(sink,
// begin grammar
'#'
<< right_align(2,'0')[hex[_1 = red()]]
<< right_align(2,'0')[hex[_1 = green()]]
<< right_align(2,'0')[hex[_1 = blue()]]
<< eps(alpha() < 255) << right_align(2,'0')[hex [_1 = alpha()]]
// end grammar
);
return str;
}
void color::premultiply()
{
agg::rgba8 pre_c = agg::rgba8(red_,green_,blue_,alpha_);
pre_c.premultiply();
red_ = pre_c.r;
green_ = pre_c.g;
blue_ = pre_c.b;
}
void color::demultiply()
{
// note: this darkens too much: https://github.com/mapnik/mapnik/issues/1519
agg::rgba8 pre_c = agg::rgba8(red_,green_,blue_,alpha_);
pre_c.demultiply();
red_ = pre_c.r;
green_ = pre_c.g;
blue_ = pre_c.b;
}
}