# define WARP 2.
# define FREQ_RANGE 20.
# define PI 3.141592653589793
# define SOUNDSOURCE iChannel2
# define WAVELENGTH 0.17
// http://lolengine.net/blog/2013/07/27/rgb-to-hsv-in-glsl
// Converting (x,y) to range [0,1]

vec3 hsv2rgb(vec3 c)
{
    vec4 K = vec4(1.0, 2.0 / 3.0, 1.0 / 3.0, 3.0);
    vec3 p = abs(fract(c.xxx + K.xyz) * 6.0 - K.www);
    return c.z * mix(K.xxx, clamp(p - K.xxx, 0.0, 1.0), c.y);
}

float getfrequency(float x) {
    return texture(SOUNDSOURCE, vec2(floor(x * FREQ_RANGE + 1.0) / FREQ_RANGE, .25)).x + 0.06;
}

float getfrequency_smooth(float x) {
    float index = floor(x * FREQ_RANGE) / FREQ_RANGE;
    float next = floor(x * FREQ_RANGE + 1.0) / FREQ_RANGE;
    return mix(getfrequency(index), getfrequency(next), smoothstep(0.0, 1.0, fract(x * FREQ_RANGE)));
}

float getfrequency_blend(float x) {
    return mix(getfrequency(x), getfrequency_smooth(x), 0.5);
}


float getMaxFreq(){
    return texture(SOUNDSOURCE, vec2(1.)).x;
}

vec3 gradients( in vec2 coord ) {

    return hsv2rgb(vec3 (
        0.5+0.5*sin(0.4*iTime*WARP)*(
            sqrt(
               (pow(0.5-0.6*cos(0.3*WARP*iTime)*(coord.x*1.77-0.385),2.))
               +
               (pow(0.7-0.4*sin(0.15*WARP*iTime)*coord.y,2.))
            )
        ),
        0.8+0.2*cos(0.2*WARP*iTime)*(
            sqrt(
               (pow(0.5-0.6*cos(0.3*WARP*iTime)*(coord.x*1.77-0.385),2.))
               +
               (pow(-0.1*cos(0.3*WARP*iTime)*coord.y,2.))
            )
        ),
        0.9+0.1*sin(WARP*iTime)*(
            sqrt(
                (pow(0.6-sin(2.*WARP*iTime)*(coord.x*1.77-0.385),2.))
                +
                (pow(0.2-cos(WARP*iTime)*coord.y,2.))
            )
        )
    ));
}

vec3 ripples( in vec2 uv, in vec2 cent ){
    float r = max(length(cent-uv),0.03);
    float wave_speed = 5.*WARP*iTime;
    return vec3 (
        1.-0.9*sin(500.*WAVELENGTH*r-wave_speed)
    );
}

vec2 yscale( float pos_x, float pos_y ){
    float y_scale = iResolution.y/iResolution.x;
    return vec2 ( pos_x, pos_y*y_scale );
}

float fade( in float f_in, in float f_out){
    float warp_time = iTime*WARP;
    float fade_duration = f_out-f_in;
    return max(0.,min(1./(f_out-f_in)*(f_out-warp_time),1.));
}

void mainImage( out vec4 fragColor, in vec2 fragCoord )
{
    float weight = 0.9;
    float pi = 3.141592653589793;
    vec2 uv = fragCoord/iResolution.xy;
    vec2 uv_c = yscale(uv.x-0.5 , uv.y-0.5);
    vec2 cent = vec2(0.5);
    float scale = iResolution.x/1920.;
    vec2 offset = yscale(-10.*WAVELENGTH, -10.*WAVELENGTH);
    vec2 cent2 = yscale(-0.7, -0.7);
    vec2 cent3 = yscale(0.7,0.7);
    vec2 cent4 = yscale(-0.7,0.7);
    vec2 cent5 = yscale(0.7,-0.7);
    vec2 cent6 = yscale(-0.05, 0.55);
    vec2 cent7 = yscale(0.05, -0.65);

    vec3 col = fade(60.,80.)*gradients(uv)*weight
               +fade(80.,60.)*(
                               hsv2rgb(vec3 (
                                   0.6*sin(1./60.*iTime)
                                   -0.5*getfrequency_smooth(
                                        sin(min(0.25,
                                                max(0.07,
                                                    0.8*length(uv_c)
                                   )))),
                                   0.99,
                                   0.3
                               )))
               -(
                   fade(25.,40.)*(
                    cos(-iTime*WARP*0.02)*ripples(uv_c,cent3)
                    +cos(-iTime*WARP*0.02)*ripples(uv_c,cent3+offset)
                    +cos(-iTime*WARP*0.02)*ripples(uv_c,cent2)
                    +cos(-iTime*WARP*0.02)*ripples(uv_c,cent2+offset)
                    +cos(-iTime*WARP*0.02)*ripples(uv_c,cent4)
                    +cos(-iTime*WARP*0.02)*ripples(uv_c,cent4+offset)
                    +cos(-iTime*WARP*0.02)*ripples(uv_c,cent5)
                    +cos(-iTime*WARP*0.02)*ripples(uv_c,cent5+offset)
                   )
                   +fade(37.,20.)*fade(50.,60.)*(
                    +2.*cos(-iTime*WARP*0.1)*ripples(uv_c,cent6)
                    +2.*cos(-iTime*WARP*0.1)*ripples(uv_c,cent6-offset)
                    +2.*cos(-iTime*WARP*0.1)*ripples(uv_c,cent7)
                    +2.*cos(-iTime*WARP*0.1)*ripples(uv_c,cent7+offset)
                   )
                   /*+fade(0.,300.)*(
                    +cos(-iTime*WARP/10.)*ripples(uv_c,cent)
                    +cos(-iTime*WARP/10.)*ripples(uv_c,cent+offset)
                   )*/
                   +fade(80.,40.)*(0.2+0.8*getfrequency_smooth(mod(iTime,1000.)))*(
                     ripples(
                         uv_c,
                         (0.9+0.1*getfrequency_smooth(mod(iTime,1000.)))
                         *vec2(-WAVELENGTH*sin(0.1*iTime*WARP),
                               -WAVELENGTH*cos(0.1*iTime*WARP))
                         +(0.95+0.05*getfrequency_smooth(0.001*mod(iTime,1000.)))
                          *0.1*vec2(1.5*WAVELENGTH*sin(2.1*iTime*WARP),
                                    1.5*WAVELENGTH*cos(2.1*iTime*WARP))
                      )
                    +ripples(
                         uv_c,
                         (0.9+0.1*getfrequency_smooth(mod(iTime,1000.)))
                         *vec2(-WAVELENGTH*sin(0.1*iTime*WARP),
                               -WAVELENGTH*cos(0.1*iTime*WARP))
                         +(0.95+0.05*getfrequency_smooth(0.001*mod(iTime,1000.)))
                          *0.1*vec2(-1.5*WAVELENGTH*sin(2.1*iTime*WARP),
                                    -1.5*WAVELENGTH*cos(2.1*iTime*WARP))
                     ))
               )*(1.-weight);

    fragColor = vec4(0.2+0.8*sqrt(col),1.);
}