#define GLSLIFY 1
uniform float time;
uniform float seed;
uniform vec2 resolution;
uniform vec2 cursor;
uniform vec2 scroll;
uniform float transition;
uniform vec2 cursorSpring;
float noise3D(vec3 p){
return fract(sin(dot(p,vec3(12.9898,78.233,128.852)))*43758.5453)*2.-1.;
}
float simplex3D(vec3 p){
float f3=1./3.;
float s=(p.x+p.y+p.z)*f3;
int i=int(floor(p.x+s));
int j=int(floor(p.y+s));
int k=int(floor(p.z+s));
float g3=1./6.;
float t=float((i+j+k))*g3;
float x0=float(i)-t;
float y0=float(j)-t;
float z0=float(k)-t;
x0=p.x-x0;
y0=p.y-y0;
z0=p.z-z0;
int i1,j1,k1;
int i2,j2,k2;
if(x0>=y0)
{
if(y0>=z0){i1=1;j1=0;k1=0;i2=1;j2=1;k2=0;}
else if(x0>=z0){i1=1;j1=0;k1=0;i2=1;j2=0;k2=1;}
else{i1=0;j1=0;k1=1;i2=1;j2=0;k2=1;}
}
else
{
if(y0<z0){i1=0;j1=0;k1=1;i2=0;j2=1;k2=1;}
else if(x0<z0){i1=0;j1=1;k1=0;i2=0;j2=1;k2=1;}
else{i1=0;j1=1;k1=0;i2=1;j2=1;k2=0;}
}
float x1=x0-float(i1)+g3;
float y1=y0-float(j1)+g3;
float z1=z0-float(k1)+g3;
float x2=x0-float(i2)+2.*g3;
float y2=y0-float(j2)+2.*g3;
float z2=z0-float(k2)+2.*g3;
float x3=x0-1.+3.*g3;
float y3=y0-1.+3.*g3;
float z3=z0-1.+3.*g3;
vec3 ijk0=vec3(i,j,k);
vec3 ijk1=vec3(i+i1,j+j1,k+k1);
vec3 ijk2=vec3(i+i2,j+j2,k+k2);
vec3 ijk3=vec3(i+1,j+1,k+1);
vec3 gr0=normalize(vec3(noise3D(ijk0),noise3D(ijk0*2.01),noise3D(ijk0*2.02)));
vec3 gr1=normalize(vec3(noise3D(ijk1),noise3D(ijk1*2.01),noise3D(ijk1*2.02)));
vec3 gr2=normalize(vec3(noise3D(ijk2),noise3D(ijk2*2.01),noise3D(ijk2*2.02)));
vec3 gr3=normalize(vec3(noise3D(ijk3),noise3D(ijk3*2.01),noise3D(ijk3*2.02)));
float n0=0.;
float n1=0.;
float n2=0.;
float n3=0.;
float t0=.5-x0*x0-y0*y0-z0*z0;
if(t0>=0.)
{
t0*=t0;
n0=t0*t0*dot(gr0,vec3(x0,y0,z0));
}
float t1=.5-x1*x1-y1*y1-z1*z1;
if(t1>=0.)
{
t1*=t1;
n1=t1*t1*dot(gr1,vec3(x1,y1,z1));
}
float t2=.5-x2*x2-y2*y2-z2*z2;
if(t2>=0.)
{
t2*=t2;
n2=t2*t2*dot(gr2,vec3(x2,y2,z2));
}
float t3=.5-x3*x3-y3*y3-z3*z3;
if(t3>=0.)
{
t3*=t3;
n3=t3*t3*dot(gr3,vec3(x3,y3,z3));
}
return 96.*(n0+n1+n2+n3);
}
float sdRect(vec2 uv,vec2 tl,vec2 br){
vec2 d=max(tl-uv,uv-br);
return length(max(vec2(0.),d))+min(0.,max(d.x,d.y));
}
void ray(inout vec4 col,inout vec2 uv){
col+=vec4(
.04*2.*simplex3D(vec3(uv/1541.325,time*.562)),
.02*2.*simplex3D(vec3(uv/1443.654,time*.315)),
.08*2.*simplex3D(vec3(uv/1612.252,time*.524)),
1.
);
}
void noise(inout vec4 col,inout vec2 uv){
col+=vec4(
.2*simplex3D(vec3(uv/1.325,time*.252)),
.1*simplex3D(vec3(uv/1.654,time*.352)),
.4*simplex3D(vec3(uv/1.252,time*.256)),
1.
);
}
void grid(inout vec4 col,inout vec2 uv){
vec2 oUv=vec2(uv);
uv*=10.;
uv.x+=sin(time+oUv.y*6.125)*.3151;
uv.y+=cos(time+oUv.x*5.5312)*.225;
uv=fract(uv)-vec2(.5);
float borderDist=1.+sdRect(uv,vec2(-.5),vec2(.5));
col=mix(col,vec4(vec3(0.,.3,.4),1.),pow(borderDist,20.)*.3);
}
float expImpulse(float x,float k){
float h=k*x;
return h*exp(1.-h);
}
void blackHole(inout vec4 col,inout vec2 uv,out float mag){
vec2 center=resolution*.5;
center+=(cursor-resolution*.5)*vec2(.1,-.1);
float dx=(uv.x-center.x)/(resolution.x*.5);
float dy=(uv.y-center.y)/(resolution.x*.5);
mag=pow(clamp(1.-sqrt(pow(dx,2.)+pow(dy,2.)),.0,1.),5.);
float dist=1.-sqrt(pow(uv.x-center.x,2.)+pow(uv.y-center.y,2.))/resolution.x;
float xMag=pow(expImpulse(fract((dist+time)/4.)*4.,4.),1.);
uv.x-=dx*(mag+xMag*.07)*10000.;
uv.y-=dy*(mag+xMag*.07)*10000.;
col=mix(col,vec4(vec3(.1,.1,.2),1.),xMag*.7);
}
void main(){
vec2 aspect=vec2(1.,resolution.y/resolution.x);
vec2 uv=gl_FragCoord.xy;
vec4 col=vec4(.04,.02,.08,1.);
float bhMag;
blackHole(col,uv,bhMag);
ray(col,uv);
uv/=resolution.xy;
uv-=vec2(.5);
uv*=aspect;
vec2 gridUv=vec2(uv);
grid(col,gridUv);
col=mix(col,vec4(vec3(.3,.8,.9),1.),pow(smoothstep(0.,.9,bhMag),.5));
col=mix(col,vec4(vec3(0.),1.),pow(smoothstep(0.,.2,bhMag),20.));
gl_FragColor=col;
}
