//******************************************************************************************
// Dreamcatcher 4k Intro   Shadertoy port
//
// All code by Jan "LJ" Scheurer
//
// Music by Jochen "Virgill" Feldkoetter
//
// http://www.pouet.net/prod.php?which=67977
// https://demozoo.org/productions/161855/
//******************************************************************************************

#define time (iChannelTime[0]-0.95)

float x(float x)
{
return abs(smoothstep(-1.,1.,time-x)*2.-1.);
}
vec2 m;
mat2 s(float m)
{
float z=sin(m),x=cos(m);
return mat2(x,z,-z,x);
}
float s(float x,float m,float z)
{
return-log(exp(-z*x)+exp(-z*m))/z;
}
float x(float x,float m,float z)
{
return-log(exp(z*x)+exp(z*m))/-z;
}
float n(vec3 m)
{
return dot(m,normalize(sign(m+1e-07)));
}
float f(vec3 m)
{
return fract(sin(dot(vec3(12,26,48),m))*49512.);
}
const vec2 v=vec2(0,1);
float f(vec3 m,vec3 x)
{
return mix(mix(f(m+v.xxx),f(m+v.yxx),x.x),mix(f(m+v.xyx),f(m+v.yyx),x.x),x.y);
}
float n(vec3 m,bool x)
{
vec3 z=floor(m),y=x?vec3(.5):fract(m);
return mix(f(z,y),f(z+v.xxy,y),y.z);
}
float p(vec3 m)
{
return n(m,false);
}
float r(vec3 m)
{
m.y*=.5;
float z=0.;
for(int x=1;x<6;x++)
{
float y=float(x*x);
z+=p(m*y)/y;
}
return z/4.;
}
float a(vec3 m)
{
return pow(r(m)+.4,3.)*4.;
}
float i(vec3 m)
{
float z=m.x,y=m.y,v=m.z,c=abs(z);
return s(s(x(-length(vec2(y+.35,v-.55))+.05,x(x(x(-abs(y+1.)+.35,x(x(mix(mix(s(mix(length(m)-.5,c-.4,
smoothstep(0.,-1.,y)*.2),min(max(c+.35,max(abs(y-.2)-.1,abs(abs(v)-.2))),max(abs(c-.4)+.3,max(abs(y-.25),
abs(v)-.12))),10.),length(vec2(c-.4,y))-.3,-.3),length(m+vec3(0.,.5,.5))-.5,-.4),-length(vec3(c-.3,y,v-.5))+.1,17.),
-length(vec3(c-.05,y+.2,v-.5))-.02,17.),6.),-length(vec2(y,v-.9))+.3,20.),-length(vec2(c-.7,y+.4))+.4+
smoothstep(.4,-.1,v)*.1,10.),15.),max(length(vec2(abs(y+.35+z*z*5.)-.035,v-.475))-.1+z*z*10.,c-.4),50.),
max(length(vec3(c-.25,y,v-.42))-.15,-y+.05+.1*cos(time*.7)-c*.4),60.)+a(m*10.)*.012;
}
float w(vec3 m)
{
return m.x=abs(m.x)-.25,m.z-=.45,length(m)-.1;
}
float d(vec3 m)
{
m.y+=1.275;
vec3 z=abs(m)-vec3(.4,.2,0.);
return s(min(max(max(z.x,z.y),z.z),length(max(z,0.))-.32),length(vec3(z.x-.2,m.y-.4,m.z-.14))-.2,30.)-a(m*2.)*.05;
}
float g(vec3 m)
{
return min(s(i(m),d(m),8.),w(m));
}
float l(vec3 m)
{
return m.xz*=s(time*.1),(r(m*3.*p(m*3.+vec2(0.,time*.2).xyx))*1.5-length(m)+1.2)*.5;
}
float e(vec3 m)
{
float z=sin(m.z*.1);
m.x+=z;
return min(a(m*.7)*2.+p(m*.3)*6.+min(m.y*3.,0.)*.5-length(m.xy)+2.+z,m.y+2.+r(m+p(m*2.)-time))*.5;
}
float y(vec3 m)
{
m.xz*=s(time*.2*step(time,122.8));
vec3 x=m;
m.xz=mod(m.xz+3.5,7.)-3.5;
for(int z=0;z<10;z++)
m.xz=abs(m.xz)-.8,m.xz*=s(.9),m.xy*=s(.8);
m=reflect(m,normalize(sign(m+1e-06))*.2);
return n(m)-.5-n(x)*.11;
}
float c(vec3 m)
{
return time<20.4?g(m):time<40.85?l(m):time<81.7?e(m):time<102.?l(m):time<143.?y(m):g(m);
}
const vec2 z=vec2(.01,0);
vec3 o(vec3 m)
{
return normalize(vec3(c(m+z.xyy)-c(m-z.xyy),c(m+z.yxy)-c(m-z.yxy),c(m+z.yyx)-c(m-z.yyx)));
}
vec3 u(vec3 m)
{
return vec3(pow(a(m*4.+a(m*15.+time))+.3,3.),.1,.7);
}
vec3 a(vec3 m,vec3 x,vec3 z,float y)
{
vec3 v=o(z),c=normalize(m-z),a=vec3(-.47,.67,.57);
float f=length(z),s=max(dot(v,a),0.),p=pow(max(dot(v,normalize(c+a)),0.),200.)*r(z*1300.)*3.,l=w(z);
return time<20.4||time>143.?l<.001?u(reflect(v,c))*.25+p*10.:vec3(.8+r(z*60.)*2.,.9,.7)*s*s+p+step(3.,f)*u(x):
min(time<40.85||time>81.7&&time<102.?(2.7-z)*pow(y,1.4):time<102.?vec3(1.,.8+max(-z.y*.7-.5,0.),.5+length(z.xy)*.12)*pow(y,1.4)+p:vec3(.3,.2+length(z)*.1,.9-length(z)*.02)*1.5*pow(y,1.4)+p,1.);
}
vec3 b(vec3 z)
{
float y=length(vec2(m.x*(time>20.4&&time<143.?.65:1.),m.y))*(step(time,20.4)*.2+.8);
return z*smoothstep(180.,167.,time)*smoothstep(0.,8.,time)*x(40.85)*x(61.)*x(81.7)*x(102.)*x(107.2)*x(112.4)*x(117.6)
*x(122.8)*x(143.)*max(1.-y*.5,0.)*(1.-y+max(y-.9,0.)*a((m*s(time*.2)).xyy*20./n(m.xyy)));
}

void mainImage( out vec4 fragColor, in vec2 fragCoord)
{

    m=(fragCoord.xy/iResolution.xy*2.-1.)*vec2(iResolution.x/iResolution.y,1.);
vec3 z,y,x;
float r,v,f=0.;
if(time<20.4||time>143.)
{
r=smoothstep(0.,20.,time-143.),v=1.-r*1.5;
z=vec3(0,.16,.65-smoothstep(15.5,20.,time)*.058+r*.8),y=normalize(vec3(m,-1.));
mat2 p=s(-.5*v),w=s(-.3*v);
z.yz*=w;
y.yz*=w;
z.xz*=p;
y.xz*=p;
}
else
 if(time<40.85||time>81.7&&time<102.)
z=vec3(0.,0.,-1.1+smoothstep(20.4,40.85,time)*2.3),y=normalize(vec3(time<81.7?m:abs(m),-1.+(time<81.7?0.:length(m)*floor((time-81.7)/5.2)*.5)));
else
 if(time<102.)
{
z=vec3(m,-time+5.),y=normalize(vec3(m,-1.75+length(m)*.5));
if(time<61.)
y.yz*=s(-1.5),y.xz*=s(time*.3);
}
else
 if(time<107.2)
z=vec3(-.5,-.8,1),y=normalize(vec3(m,-1.3)),y.yz*=s(1.4);
else if(time<112.4)
z=vec3(1.,-.75+(time-107.2)*.1,1.-(time-107.2)*.2),y=normalize(vec3(m,-.7)),y.yz*=s(1.4);
else if(time<117.6)
z=vec3(0,-.8+(time-112.4)*.2,0),y=normalize(vec3(m,-1)).xzy;
else if(time<122.8)
z=vec3(0.,1.-(time-117.7)*.2,0.),y=normalize(vec3(m,-1.));
else if(time<143.)
z=vec3(0.,1.,-5.+(time-117.7)*.2),y=normalize(vec3(m*s(time*.2),-1.+smoothstep(0.,21.,time-122.8)*.8));

int p;
for(int i=0;i<70;i++)
{
p=i;
x=z+y*f;
float w=c(x);
if(w<.0001)
break;
f+=w;
}
f=float(p)/60.;
fragColor=vec4(b(a(z,y,x,f)),1.);
}