60 lines
1.2 KiB
GLSL
60 lines
1.2 KiB
GLSL
#version 330 core
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out vec4 fragColor;
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uniform float u_time;
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uniform uint u_frame;
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uniform vec2 u_resolution;
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uniform vec2 u_mouse;
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// Source: https://github.com/kbinani/colormap-shaders/blob/master/shaders/glsl/MATLAB_jet.frag
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float colormap_red(float x) {
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if (x < 0.7) {
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return 4.0 * x - 1.5;
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} else {
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return -4.0 * x + 4.5;
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}
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}
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float colormap_green(float x) {
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if (x < 0.5) {
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return 4.0 * x - 0.5;
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} else {
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return -4.0 * x + 3.5;
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}
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}
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float colormap_blue(float x) {
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if (x < 0.3) {
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return 4.0 * x + 0.5;
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} else {
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return -4.0 * x + 2.5;
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}
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}
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vec4 colormap(float x) {
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float r = clamp(colormap_red(x), 0.0, 1.0);
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float g = clamp(colormap_green(x), 0.0, 1.0);
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float b = clamp(colormap_blue(x), 0.0, 1.0);
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return vec4(r, g, b, 1.0);
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}
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// Mandelbrot
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vec2 f(vec2 z) {
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vec2 c = gl_FragCoord.xy / u_resolution.xy * 2.6 - vec2(2.0, 1.3);
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return vec2(z.x * z.x - z.y * z.y, 2 * z.x * z.y) + c;
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}
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void main() {
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vec2 z = vec2(0.0);
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int i = 0;
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while (length(z) <= 2 && i < 1000) {
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z = f(z);
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i++;
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}
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if (i == 1000) {
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fragColor = vec4(vec3(0.0), 1.0);
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} else {
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fragColor = colormap(smoothstep(0.0, 23.0, i));
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}
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}
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