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https://github.com/w23/xash3d-fwgs
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5e0a0765ce
The `.editorconfig` file in this repo is configured to trim all trailing whitespace regardless of whether the line is modified. Trims all trailing whitespace in the repository to make the codebase easier to work with in editors that respect `.editorconfig`. `git blame` becomes less useful on these lines but it already isn't very useful. Commands: ``` find . -type f -name '*.h' -exec sed --in-place 's/[[:space:]]\+$//' {} \+ find . -type f -name '*.c' -exec sed --in-place 's/[[:space:]]\+$//' {} \+ ```
88 lines
2.2 KiB
C
88 lines
2.2 KiB
C
/*
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gamma.c - gamma routines
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Copyright (C) 2011 Uncle Mike
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This program is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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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
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GNU General Public License for more details.
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*/
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#include "common.h"
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#include "xash3d_mathlib.h"
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//-----------------------------------------------------------------------------
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// Gamma conversion support
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//-----------------------------------------------------------------------------
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static byte texgammatable[256]; // palette is sent through this to convert to screen gamma
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static byte lightgammatable[256];
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static int lineargammatable[1024];
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static int screengammatable[1024];
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void BuildGammaTable( float lightgamma, float brightness )
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{
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int i, inf;
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float f, g, g1, g3;
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lightgamma = bound( 1.8f, lightgamma, 3.0f );
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brightness = bound( 0.0f, brightness, 10.0f );
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if( brightness <= 0.0f )
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g3 = 0.125f;
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else if( brightness > 1.0f )
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g3 = 0.05f;
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else g3 = 0.125f - (brightness * brightness) * 0.075f;
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g = 1.0f / lightgamma;
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g1 = GAMMA * g;
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for( i = 0; i < 256; i++ )
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{
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f = pow( i / 255.f, GAMMA );
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// scale up
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if( brightness > 1.0f )
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f = f * brightness;
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// shift up
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if( f <= g3 ) f = (f / g3) * 0.125f;
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else f = 0.125f + ((f - g3) / (1.0f - g3)) * 0.875f;
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// convert linear space to desired gamma space
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inf = (int)( 255.0f * pow( f, g ));
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lightgammatable[i] = bound( 0, inf, 255 );
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}
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for( i = 0; i < 256; i++ )
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{
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f = 255.0f * pow(( float )i / 255.0f, TEXGAMMA );
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inf = (int)(f + 0.5f);
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texgammatable[i] = bound( 0, inf, 255 );
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}
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for( i = 0; i < 1024; i++ )
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{
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// convert from screen gamma space to linear space
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lineargammatable[i] = 1023 * pow( i / 1023.0f, g1 );
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// convert from linear gamma space to screen space
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screengammatable[i] = 1023 * pow( i / 1023.0f, 1.0f / g1 );
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}
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}
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byte LightToTexGamma( byte b )
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{
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return lightgammatable[b];
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}
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byte TextureToGamma( byte b )
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{
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return texgammatable[b];
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}
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