59 lines
1.4 KiB
C
59 lines
1.4 KiB
C
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/*
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* DDS PIKA plugin
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*
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* Copyright (C) 2004-2012 Shawn Kirst <skirst@gmail.com>,
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* with parts (C) 2003 Arne Reuter <homepage@arnereuter.de> where specified.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public
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* License as published by the Free Software Foundation; either
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* version 2 of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; see the file COPYING. If not, write to
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* the Free Software Foundation, 51 Franklin Street, Fifth Floor
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* Boston, MA 02110-1301, USA.
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*/
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#include <math.h>
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#include "color.h"
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int
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linear_to_sRGB(int c)
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{
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float v = (float)c / 255.0f;
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if(v < 0)
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v = 0;
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else if(v > 1)
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v = 1;
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else if(v <= 0.0031308f)
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v = 12.92f * v;
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else
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v = 1.055f * powf(v, 0.41666f) - 0.055f;
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return (int)floorf(255.0f * v + 0.5f);
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}
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int
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sRGB_to_linear(int c)
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{
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float v = (float)c / 255.0f;
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if(v < 0)
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v = 0;
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else if(v > 1)
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v = 1;
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else if(v <= 0.04045f)
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v /= 12.92f;
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else
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v = powf((v + 0.055f) / 1.055f, 2.4f);
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return (int)floorf(255.0f * v + 0.5f);
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}
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