gr-fosphor/lib/fosphor/cmap_simple.glsl

50 lines
1.3 KiB
GLSL

/*
* cmap_simple.glsl
*
* Color mapping shader - Nearest/Bilinear version
*
* Copyright (C) 2013-2021 Sylvain Munaut
* SPDX-License-Identifier: GPL-3.0-or-later
*
* Note (to make it clear): for the purpose of this license, any software
* making use of this shader (or derivative thereof) is considered to be
* a derivative work (i.e. "a work based on the program").
*/
/* Require GLSL 1.5 compatibility profile to build without warning
* But we use 1.3 since some cards don't allow 1.5 compatibility but
* will work with 1.3
*/
/* #version 150 compatibility */
#version 130
/* ------------------------------------------------------------------------ */
/* Main fragment shader code */
/* ------------------------------------------------------------------------ */
/* Uniforms */
uniform sampler1D palette; /* 1D texture with the color to map to */
uniform sampler2D tex; /* 2D intensity texture */
uniform vec2 range; /* (scale, offset) vector */
/* In/Out */
out vec4 out_FragColor;
/* Shader main */
void main()
{
float intensity = texture(tex, gl_TexCoord[0].st).x;
float map = (intensity + range.y) * range.x;
vec4 color = texture(palette, map);
out_FragColor = color;
}
/* vim: set syntax=c: */