libcruft-util/colour.cpp

102 lines
3.0 KiB
C++

/*
* This file is part of libgim.
*
* libgim is free software: you can redistribute it and/or modify it under the
* terms of the GNU General Public License as published by the Free Software
* Foundation, either version 3 of the License, or (at your option) any later
* version.
*
* libgim 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 General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with libgim. If not, see <http://www.gnu.org/licenses/>.
*
* Copyright 2010-2013 Danny Robson <danny@nerdcruft.net>
*/
#include "colour.hpp"
#include "range.hpp"
#include "random.hpp"
//-----------------------------------------------------------------------------
using util::colour;
using util::colour4f;
//-----------------------------------------------------------------------------
#define CONSTANT_COLOUR(NAME,R,G,B) \
template <size_t S, typename T> \
const util::colour<S,T> \
util::colour<S,T>::NAME = \
util::colour<4,float> (R,G,B,1) \
.template redim<S> () \
.template cast<T> ();
CONSTANT_COLOUR(WHITE,1,1,1);
CONSTANT_COLOUR(BLACK,0,0,0);
CONSTANT_COLOUR(RED, 1,0,0);
CONSTANT_COLOUR(GREEN,0,1,0);
CONSTANT_COLOUR(BLUE, 0,0,1);
///----------------------------------------------------------------------------
//! Extract a colour object from a JSON node.
//!
//! Data must be an array or 3 or 4 numbers. Guarantees success, or throws a
//! json::tree::type_error.
const json::tree::node&
operator>> (const json::tree::node &node, util::colour4f &c) {
c.r = static_cast<float> (node[0].as_number ());
c.g = static_cast<float> (node[1].as_number ());
c.b = static_cast<float> (node[2].as_number ());
try {
c.a = static_cast<float> (node[3].as_number ());
} catch (...) {
c.a = 1;
}
return node;
}
//-----------------------------------------------------------------------------
namespace util {
template<>
colour4f
random (void) {
return colour4f ({ range<float>::UNIT.random (),
range<float>::UNIT.random (),
range<float>::UNIT.random (),
range<float>::UNIT.random () });
}
template <>
colour4f&
randomise (colour4f &c)
{ return c = random<colour4f> (); }
}
//-----------------------------------------------------------------------------
std::ostream&
util::operator<< (std::ostream &os, const util::colour4f &c) {
os << "colour(" << c.r << ", " << c.g << ", " << c.b << ", " << c.a << ")";
return os;
}
//-----------------------------------------------------------------------------
template struct util::colour<3,float>;
template struct util::colour<3,double>;
template struct util::colour<4,float>;
template struct util::colour<4,double>;