59 lines
1.4 KiB
C
59 lines
1.4 KiB
C
/*
|
|
* DDS PIKA plugin
|
|
*
|
|
* Copyright (C) 2004-2012 Shawn Kirst <skirst@gmail.com>,
|
|
* with parts (C) 2003 Arne Reuter <homepage@arnereuter.de> where specified.
|
|
*
|
|
* This program 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 program 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 this program; see the file COPYING. If not, write to
|
|
* the Free Software Foundation, 51 Franklin Street, Fifth Floor
|
|
* Boston, MA 02110-1301, USA.
|
|
*/
|
|
|
|
#include <math.h>
|
|
#include "color.h"
|
|
|
|
int
|
|
linear_to_sRGB(int c)
|
|
{
|
|
float v = (float)c / 255.0f;
|
|
|
|
if(v < 0)
|
|
v = 0;
|
|
else if(v > 1)
|
|
v = 1;
|
|
else if(v <= 0.0031308f)
|
|
v = 12.92f * v;
|
|
else
|
|
v = 1.055f * powf(v, 0.41666f) - 0.055f;
|
|
|
|
return (int)floorf(255.0f * v + 0.5f);
|
|
}
|
|
|
|
int
|
|
sRGB_to_linear(int c)
|
|
{
|
|
float v = (float)c / 255.0f;
|
|
|
|
if(v < 0)
|
|
v = 0;
|
|
else if(v > 1)
|
|
v = 1;
|
|
else if(v <= 0.04045f)
|
|
v /= 12.92f;
|
|
else
|
|
v = powf((v + 0.055f) / 1.055f, 2.4f);
|
|
|
|
return (int)floorf(255.0f * v + 0.5f);
|
|
}
|
