ShaderBasis Example
Same example from https://github.com/DangerCenter/shaderbasis
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Shader
void mainImage( out vec4 fragColor, in vec2 fragCoord ) {
vec2 position = 2. * (fragCoord.xy / iResolution.xy) - 1.;
vec3 colour = vec3(0.0);
float density = 0.15;
float amplitude = 0.3;
float frequency = 5.0;
float scroll = 0.4;
colour += vec3(0.1, 0.05, 0.05) * (1.0 / abs((position.y + (amplitude * sin(((position.x-0.0) + iTime * scroll) *frequency)))) * density);
colour += vec3(0.05, 0.1, 0.05) * (1.0 / abs((position.y + (amplitude * sin(((position.x-0.3) + iTime * scroll) *frequency)))) * density);
colour += vec3(0.05, 0.05, 0.1) * (1.0 / abs((position.y + (amplitude * sin(((position.x-0.6) + iTime * scroll) *frequency)))) * density);
//
fragColor = vec4( colour, 1.0 );
}