-/* === S Y N F I G ========================================================= */
-/*! \file color.cpp
-** \brief Color Class
-**
-** $Id$
-**
-** \legal
-** Copyright (c) 2002-2005 Robert B. Quattlebaum Jr., Adrian Bentley
-** Copyright (c) 2007, 2008 Chris Moore
-**
-** This package 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 2 of
-** the License, or (at your option) any later version.
-**
-** This package 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.
-** \endlegal
-*/
-/* ========================================================================= */
-
-/* === H E A D E R S ======================================================= */
-
-#ifdef USING_PCH
-# include "pch.h"
-#else
-#ifdef HAVE_CONFIG_H
-# include <config.h>
-#endif
-
-#include <ETL/angle>
-#include "color.h"
-#include <cstdio>
-#include <sstream>
-#include <iostream>
-#include <iomanip>
-
-#endif
-
-using namespace synfig;
-using namespace etl;
-using namespace std;
-
-/* === M A C R O S ========================================================= */
-
-#define COLOR_EPSILON (0.000001f)
-
-/* === G L O B A L S ======================================================= */
-
-/* === P R O C E D U R E S ================================================= */
-
-/* === M E T H O D S ======================================================= */
-
-
-
-ColorReal
-Color::hex2real(String s)
-{
- std::istringstream i(s);
- int n;
- i.fill('0');
- if (!(i >> hex >> n))
- throw String("bad conversion from hex string \"") + s + String("\"");
- return n / 255.0f;
-}
-
-const String
-Color::real2hex(ColorReal c)
-{
- std::ostringstream o;
- o.width(2);
- o.fill('0');
- if (c<0) c = 0;
- if (c>1) c = 1;
- o << hex << int(c*255.0f);
- return o.str();
-}
-
-void
-Color::set_hex(String& str)
-{
- value_type r, g, b;
- String hex;
-
- // use just the hex characters
- for (String::const_iterator iter = str.begin(); iter != str.end(); iter++)
- if (isxdigit(*iter))
- hex.push_back(*iter);
-
- try
- {
- if (hex.size() == 1)
- {
- r = hex2real(hex.substr(0,1)+hex.substr(0,1));
- r_ = g_ = b_ = r;
- }
- else if (hex.size() == 3)
- {
- r = hex2real(hex.substr(0,1)+hex.substr(0,1));
- g = hex2real(hex.substr(1,1)+hex.substr(1,1));
- b = hex2real(hex.substr(2,1)+hex.substr(2,1));
- r_ = r; g_ = g; b_ = b;
- }
- else if (hex.size() == 6)
- {
- r = hex2real(hex.substr(0,2));
- g = hex2real(hex.substr(2,2));
- b = hex2real(hex.substr(4,2));
- r_ = r; g_ = g; b_ = b;
- }
- }
- catch (string s)
- {
- printf("caught <%s>\n", s.c_str());
- return;
- }
-}
-
-const String
-Color::get_string(void)const
-{
- std::ostringstream o;
- o << std::fixed << std::setprecision(3) << "#" << get_hex() << " : " << std::setw(6) << a_;
- return String(o.str().c_str());
-}
-
-#if 0
-Color&
-Color::rotate_uv(const Angle& theta)const
-{
-/*/
- Color ret(*this);
- ret.set_hue(ret.get_hue()+theta);
- return ret;
-/*/
- const float
- a(angle::sin(theta).get()),
- b(angle::cos(theta).get());
- const float
- u(get_u()),
- v(get_v());
-
- return set_uv(b*u-a*v,a*u+b*v);
- //return YUV(get_y(),b*u-a*v,a*u+b*v,get_a());
-//*/
-}
-#endif
-
-Color
-Color::clamped_negative()const
-{
- Color ret=*this;
-
- if(ret.a_==0)
- return alpha();
-
- if(ret.a_<0)
- ret=-ret;
-
- if(ret.r_<0)
- {
- ret.g_-=ret.r_;
- ret.b_-=ret.r_;
- ret.r_=0.0f;
- }
- if(ret.g_<0)
- {
- ret.r_-=ret.g_;
- ret.b_-=ret.g_;
- ret.g_=0.0f;
- }
- if(ret.b_<0)
- {
- ret.r_-=ret.b_;
- ret.g_-=ret.b_;
- ret.b_=0.0f;
- }
-
- if(ret.r_>1) ret.r_=1;
- if(ret.g_>1) ret.g_=1;
- if(ret.b_>1) ret.b_=1;
- if(ret.a_>1) ret.a_=1;
-
- if(isnan(ret.get_r())) ret.r_=0.5;
- if(isnan(ret.get_g())) ret.g_=0.5;
- if(isnan(ret.get_b())) ret.b_=0.5;
- if(isnan(ret.get_a())) ret.a_=1;
-
-/*
- if(ret.r_>1) { ret.g_/=ret.r_; ret.b_/=ret.r_; ret.r_=1; }
- if(ret.g_>1) { ret.r_/=ret.g_; ret.b_/=ret.g_; ret.g_=1; }
- if(ret.b_>1) { ret.g_/=ret.b_; ret.r_/=ret.b_; ret.b_=1; }
- if(ret.a_>1) ret.a_=1;
-*/
-
- return ret;
-}
-
-Color
-Color::clamped()const
-{
- Color ret(*this);
- if(ret.get_r()<0)
- ret.set_r(0);
- if(ret.get_g()<0)
- ret.set_g(0);
- if(ret.get_b()<0)
- ret.set_b(0);
- if(ret.get_a()<0)
- ret.set_a(0);
-
- if(ret.r_>1) ret.r_=1;
- if(ret.g_>1) ret.g_=1;
- if(ret.b_>1) ret.b_=1;
- if(ret.a_>1) ret.a_=1;
-
- if(isnan(ret.get_r())) ret.r_=0.5;
- if(isnan(ret.get_g())) ret.g_=0.5;
- if(isnan(ret.get_b())) ret.b_=0.5;
- if(isnan(ret.get_a())) ret.a_=1;
-
- return(ret);
-}
-
-typedef Color (*blendfunc)(Color &,Color &,float);
-
-static Color
-blendfunc_COMPOSITE(Color &src,Color &dest,float amount)
-{
- //c_dest'=c_src+(1.0-a_src)*c_dest
- //a_dest'=a_src+(1.0-a_src)*a_dest
-
- float a_src=src.get_a()*amount;
- float a_dest=dest.get_a();
-
- // if a_arc==0.0
- //if(fabsf(a_src)<COLOR_EPSILON) return dest;
-
- // Scale the source and destination by their alpha values
- src*=a_src;
- dest*=a_dest;
-
- dest=src + dest*(1.0f-a_src);
-
- a_dest=a_src + a_dest*(1.0f-a_src);
-
- // if a_dest!=0.0
- if(fabsf(a_dest)>COLOR_EPSILON)
- {
- dest/=a_dest;
- dest.set_a(a_dest);
- }
- else
- {
- dest=Color::alpha();
- }
- assert(dest.is_valid());
- return dest;
-}
-
-static Color
-blendfunc_STRAIGHT(Color &src,Color &bg,float amount)
-{
- //a_out'=(a_src-a_bg)*amount+a_bg
- //c_out'=(((c_src*a_src)-(c_bg*a_bg))*amount+(c_bg*a_bg))/a_out'
-
- // ie: if(amount==1.0)
- //if(fabsf(amount-1.0f)<COLOR_EPSILON)return src;
-
- Color out;
-
- float a_out((src.get_a()-bg.get_a())*amount+bg.get_a());
-
- // if a_out!=0.0
- if(fabsf(a_out)>COLOR_EPSILON)
-// if(a_out>COLOR_EPSILON || a_out<-COLOR_EPSILON)
- {
- out=((src*src.get_a()-bg*bg.get_a())*amount+bg*bg.get_a())/a_out;
- out.set_a(a_out);
- }
- else
- out=Color::alpha();
-
- assert(out.is_valid());
- return out;
-}
-
-static Color
-blendfunc_ONTO(Color &a,Color &b,float amount)
-{
- float alpha(b.get_a());
- return blendfunc_COMPOSITE(a,b.set_a(1.0f),amount).set_a(alpha);
-}
-
-static Color
-blendfunc_STRAIGHT_ONTO(Color &a,Color &b,float amount)
-{
- a.set_a(a.get_a()*b.get_a());
- return blendfunc_STRAIGHT(a,b,amount);
-}
-
-static Color
-blendfunc_BRIGHTEN(Color &a,Color &b,float amount)
-{
- const float alpha(a.get_a()*amount);
-
- if(b.get_r()<a.get_r()*alpha)
- b.set_r(a.get_r()*alpha);
-
- if(b.get_g()<a.get_g()*alpha)
- b.set_g(a.get_g()*alpha);
-
- if(b.get_b()<a.get_b()*alpha)
- b.set_b(a.get_b()*alpha);
-
- return b;
-}
-
-static Color
-blendfunc_DARKEN(Color &a,Color &b,float amount)
-{
- const float alpha(a.get_a()*amount);
-
- if(b.get_r()>(a.get_r()-1.0f)*alpha+1.0f)
- b.set_r((a.get_r()-1.0f)*alpha+1.0f);
-
- if(b.get_g()>(a.get_g()-1.0f)*alpha+1.0f)
- b.set_g((a.get_g()-1.0f)*alpha+1.0f);
-
- if(b.get_b()>(a.get_b()-1.0f)*alpha+1.0f)
- b.set_b((a.get_b()-1.0f)*alpha+1.0f);
-
-
- return b;
-}
-
-static Color
-blendfunc_ADD(Color &a,Color &b,float amount)
-{
- const float alpha(a.get_a()*amount);
-
- b.set_r(b.get_r()+a.get_r()*alpha);
- b.set_g(b.get_g()+a.get_g()*alpha);
- b.set_b(b.get_b()+a.get_b()*alpha);
-
- return b;
-}
-
-static Color
-blendfunc_SUBTRACT(Color &a,Color &b,float amount)
-{
- const float alpha(a.get_a()*amount);
-
- b.set_r(b.get_r()-a.get_r()*alpha);
- b.set_g(b.get_g()-a.get_g()*alpha);
- b.set_b(b.get_b()-a.get_b()*alpha);
-
- return b;
-}
-
-static Color
-blendfunc_DIFFERENCE(Color &a,Color &b,float amount)
-{
- const float alpha(a.get_a()*amount);
-
- b.set_r(abs(b.get_r()-a.get_r()*alpha));
- b.set_g(abs(b.get_g()-a.get_g()*alpha));
- b.set_b(abs(b.get_b()-a.get_b()*alpha));
-
- return b;
-}
-
-static Color
-blendfunc_MULTIPLY(Color &a,Color &b,float amount)
-{
- if(amount<0) a=~a, amount=-amount;
-
- amount*=a.get_a();
- b.set_r(((b.get_r()*a.get_r())-b.get_r())*(amount)+b.get_r());
- b.set_g(((b.get_g()*a.get_g())-b.get_g())*(amount)+b.get_g());
- b.set_b(((b.get_b()*a.get_b())-b.get_b())*(amount)+b.get_b());
- return b;
-}
-
-static Color
-blendfunc_DIVIDE(Color &a,Color &b,float amount)
-{
- amount*=a.get_a();
-
- // We add COLOR_EPSILON in order to avoid a divide-by-zero condition.
- // This causes DIVIDE to bias toward positive values, but the effect is
- // really negligible. There is a reason why we use COLOR_EPSILON--we
- // want the change to be imperceptible.
-
- b.set_r(((b.get_r()/(a.get_r()+COLOR_EPSILON))-b.get_r())*(amount)+b.get_r());
- b.set_g(((b.get_g()/(a.get_g()+COLOR_EPSILON))-b.get_g())*(amount)+b.get_g());
- b.set_b(((b.get_b()/(a.get_b()+COLOR_EPSILON))-b.get_b())*(amount)+b.get_b());
-
- return b;
-}
-
-static Color
-blendfunc_COLOR(Color &a,Color &b,float amount)
-{
- Color temp(b);
- temp.set_uv(a.get_u(),a.get_v());
- return (temp-b)*amount*a.get_a()+b;
-}
-
-static Color
-blendfunc_HUE(Color &a,Color &b,float amount)
-{
- Color temp(b);
- temp.set_hue(a.get_hue());
- return (temp-b)*amount*a.get_a()+b;
-}
-
-static Color
-blendfunc_SATURATION(Color &a,Color &b,float amount)
-{
- Color temp(b);
- temp.set_s(a.get_s());
- return (temp-b)*amount*a.get_a()+b;
-}
-
-static Color
-blendfunc_LUMINANCE(Color &a,Color &b,float amount)
-{
- Color temp(b);
- temp.set_y(a.get_y());
- return (temp-b)*amount*a.get_a()+b;
-}
-
-static Color
-blendfunc_BEHIND(Color &a,Color &b,float amount)
-{
- if(a.get_a()==0)a.set_a(COLOR_EPSILON); //!< \todo this is a hack
- a.set_a(a.get_a()*amount);
- return blendfunc_COMPOSITE(b,a,1.0);
-}
-
-static Color
-blendfunc_ALPHA_BRIGHTEN(Color &a,Color &b,float amount)
-{
- // \todo can this be right, multiplying amount by *b*'s alpha?
- // compare with blendfunc_BRIGHTEN where it is multiplied by *a*'s
- if(a.get_a() < b.get_a()*amount)
- return a.set_a(a.get_a()*amount);
- return b;
-}
-
-static Color
-blendfunc_ALPHA_DARKEN(Color &a,Color &b,float amount)
-{
- if(a.get_a()*amount > b.get_a())
- return a.set_a(a.get_a()*amount);
- return b;
-}
-
-static Color
-blendfunc_SCREEN(Color &a,Color &b,float amount)
-{
- if(amount<0) a=~a, amount=-amount;
-
- a.set_r(1.0-(1.0f-a.get_r())*(1.0f-b.get_r()));
- a.set_g(1.0-(1.0f-a.get_g())*(1.0f-b.get_g()));
- a.set_b(1.0-(1.0f-a.get_b())*(1.0f-b.get_b()));
-
- return blendfunc_ONTO(a,b,amount);
-}
-
-static Color
-blendfunc_OVERLAY(Color &a,Color &b,float amount)
-{
- if(amount<0) a=~a, amount=-amount;
-
- Color rm;
- rm.set_r(b.get_r()*a.get_r());
- rm.set_g(b.get_g()*a.get_g());
- rm.set_b(b.get_b()*a.get_b());
-
- Color rs;
- rs.set_r(1.0-(1.0f-a.get_r())*(1.0f-b.get_r()));
- rs.set_g(1.0-(1.0f-a.get_g())*(1.0f-b.get_g()));
- rs.set_b(1.0-(1.0f-a.get_b())*(1.0f-b.get_b()));
-
- Color& ret(a);
-
- ret.set_r(a.get_r()*rs.get_r() + (1.0-a.get_r())*rm.get_r());
- ret.set_g(a.get_g()*rs.get_g() + (1.0-a.get_g())*rm.get_g());
- ret.set_b(a.get_b()*rs.get_b() + (1.0-a.get_b())*rm.get_b());
-
- return blendfunc_ONTO(ret,b,amount);
-}
-
-static Color
-blendfunc_HARD_LIGHT(Color &a,Color &b,float amount)
-{
- if(amount<0) a=~a, amount=-amount;
-
- if(a.get_r()>0.5f) a.set_r(1.0-(1.0f-(a.get_r()*2.0f-1.0f))*(1.0f-b.get_r()));
- else a.set_r(b.get_r()*(a.get_r()*2.0f));
- if(a.get_g()>0.5f) a.set_g(1.0-(1.0f-(a.get_g()*2.0f-1.0f))*(1.0f-b.get_g()));
- else a.set_g(b.get_g()*(a.get_g()*2.0f));
- if(a.get_b()>0.5f) a.set_b(1.0-(1.0f-(a.get_b()*2.0f-1.0f))*(1.0f-b.get_b()));
- else a.set_b(b.get_b()*(a.get_b()*2.0f));
-
- return blendfunc_ONTO(a,b,amount);
-}
-
-static Color
-blendfunc_ALPHA_OVER(Color &a,Color &b,float amount)
-{
- Color rm(b);
-
- //multiply the inverse alpha channel with the one below us
- rm.set_a((1-a.get_a())*b.get_a());
-
- return blendfunc_STRAIGHT(rm,b,amount);
-}
-
-
-Color
-Color::blend(Color a, Color b,float amount, Color::BlendMethod type)
-{
-#if 0
- if(isnan(a.get_r()) || isnan(a.get_g()) || isnan(a.get_b()))
- {
-#ifdef _DEBUG
- a=magenta().set_a(a.get_a());
-#else
- a=black().set_a(a.get_a());
-#endif
- }
-
- if(isnan(b.get_r()) || isnan(b.get_g()) || isnan(b.get_b()))
- {
-#ifdef _DEBUG
- b=magenta().set_a(b.get_a());
-#else
- b=black().set_a(b.get_a());
-#endif
- }
-#endif
-
-/*
- if(!a.is_valid()&&b.is_valid())
- return b;
-
- if(a.is_valid()&&!b.is_valid())
- return a;
-
- if(!a.is_valid()||!b.is_valid())
- {
-#ifdef _DEBUG
- return magenta();
-#else
- return black();
-#endif
- }
-*/
-
- // No matter what blend method is being used,
- // if the amount is equal to zero, then only B
- // will shine through
- if(fabsf(amount)<=COLOR_EPSILON)return b;
-
- assert(type<BLEND_END);
-
- const static blendfunc vtable[BLEND_END]=
- {
- blendfunc_COMPOSITE, // 0
- blendfunc_STRAIGHT,
- blendfunc_BRIGHTEN,
- blendfunc_DARKEN,
- blendfunc_ADD,
- blendfunc_SUBTRACT, // 5
- blendfunc_MULTIPLY,
- blendfunc_DIVIDE,
- blendfunc_COLOR,
- blendfunc_HUE,
- blendfunc_SATURATION, // 10
- blendfunc_LUMINANCE,
- blendfunc_BEHIND,
- blendfunc_ONTO,
- blendfunc_ALPHA_BRIGHTEN,
- blendfunc_ALPHA_DARKEN, // 15
- blendfunc_SCREEN,
- blendfunc_HARD_LIGHT,
- blendfunc_DIFFERENCE,
- blendfunc_ALPHA_OVER,
- blendfunc_OVERLAY, // 20
- blendfunc_STRAIGHT_ONTO,
- };
-
- return vtable[type](a,b,amount);
-}