TinyChan

//Started: 19 Aug 2024 13:56:32. Finished: 14:19:48.
//Moving points connected with lines to make a waveform.
rand=Math.random;
pToLine=(a,b,x)=>a.y+((b.y-a.y)*(x-a.x)/(b.x-a.x));
function makeChordSynth(count=5){
  let p=[];
  for(let i=0;i<count;i++){
    p.push({x:rand(),y:rand(),vx:(rand()*2)-1,vy:(rand()*2)-1});
  }
  p.sort((a,b)=>a.x-b.x);
  function step(speed=1){
     for(let i=0;i<p.length;i++){
       p[i].x+=p[i].vx*speed;
            if(p[i].x>1){p[i].x=1-(p[i].vx*speed);p[i].vx*=-1;}
       else if(p[i].x<0){p[i].x=0-(p[i].vx*speed);p[i].vx*=-1;}
       p[i].y+=p[i].vy*speed;
            if(p[i].y>1){p[i].y=1-(p[i].vy*speed);p[i].vy*=-1;}
       else if(p[i].y<0){p[i].y=0-(p[i].vy*speed);p[i].vy*=-1;}
     }
     p.sort((a,b)=>a.x-b.x);
  }
  function wave(x){
    //p must be in order first
    //p positions must be within the range [0,1] (but this returns in range [-1,1])
    if(x>=0&&x<=p[0].x){return(pToLine({x:p[p.length-1].x-1,y:p[p.length-1].y},p[0],x)*2)-1;}
    if(x>=p[p.length-1].x&&x<=1){return(pToLine(p[p.length-1],{x:p[0].x+1,y:p[0].y},x)*2)-1;}
    for(let i=0;i<p.length-1;i++){
      if(x>=p[i].x&&x<=p[i+1].x){ //This could be improved? (By going backwards and only using one comparison?)
        return(pToLine(p[i],p[i+1],x)*2)-1;
      }
    }
  }
  return(t)=>{
    step(1e-6+(sin(t/20)*1e-5));
    return(wave((t*60)%1)+wave((t*90)%1)+wave((t*200)%1)+wave((t*302)%1)+wave((t*480)%1))*.3;
  };
}
a=[
  //[synth,speed,LFO]
  [makeChordSynth(4),1.61,.2],
  [makeChordSynth(6),1.2,.6],
  [makeChordSynth(12),.401,.5]
];
return(t)=>{
  let m=[0,0];
  for(let i=0;i<a.length;i++){
    m[0]+=a[i][0](t*a[i][1])*sin(t*a[i][2]);
    m[1]+=a[i][0](t*a[i][1])*cos(t*a[i][2]);
  }
  return[m[0]/2,m[1]/2];
};