36 lines
1.0 KiB
GLSL
36 lines
1.0 KiB
GLSL
/*
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* cmap_fallback.glsl
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*
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* Color mapping shader - Fall back GLSL 1.0 compatibility version
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*
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* Copyright (C) 2013-2021 Sylvain Munaut
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* SPDX-License-Identifier: GPL-3.0-or-later
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*
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* Note (to make it clear): for the purpose of this license, any software
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* making use of this shader (or derivative thereof) is considered to be
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* a derivative work (i.e. "a work based on the program").
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*/
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/* ------------------------------------------------------------------------ */
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/* Main fragment shader code */
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/* ------------------------------------------------------------------------ */
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/* Uniforms */
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uniform sampler1D palette; /* 1D texture with the color to map to */
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uniform sampler2D tex; /* 2D intensity texture */
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uniform vec2 range; /* (scale, offset) vector */
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/* Shader main */
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void main()
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{
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float intensity = texture2D(tex, gl_TexCoord[0].st).x;
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float map = (intensity + range.y) * range.x;
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vec4 color = texture1D(palette, map);
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gl_FragColor = color;
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}
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/* vim: set syntax=c: */
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