Function tick

packages/webapp/components/world/engine/world.js:10543–10653

()

   hidden tab pauses rAF, and the only way to step the world in that state is to
   have a tick that does not re-queue itself. */
function tick(){
  if(disposed)return;
  const t=clock.getElapsedTime(), dt=Math.min(0.05,t-last); last=t;
  /* The overlay covers the whole canvas with an opaque surface for as long as
     this is loading, and a frame costs three passes over the scene plus a label
     solve. Painting them under it is what was stealing time from the chunked
     build the progress bar is reporting on. boot() draws one real frame the
     moment it flips to ready, so nothing is ever revealed unpainted. */
  const curtained=STATE.status==='loading';
  if(resizeDirty){ resizeDirty=false; reflow(); }

  if(W){
    /* Before anything reads DAY this frame, and before the land rebuild below,
       so a scrubbed day is fully standing by the time this frame draws. */
    flushSeek();
    if(playing){
      acc+=dt*DPS*speed;
      let stepped=false;
      while(acc>=1&&DAY<W.nT-1){ acc-=1; step(DAY+1); stepped=true; }
      /* Once for the frame, not once per day crossed. At 16x a frame can cross
         two dozen days, and only the last one is ever drawn or emitted — the
         per-day work inside step (toasts, pulses, level-up queueing) stays
         where it is, because those are events rather than a state to paint. */
      if(stepped) updateHud();
      if(DAY>=W.nT-1) stop();
    }
    /* A realm's LAND only changes ten times over a whole history, but the
       monuments standing on it change constantly — and refreshing a realm costs
       ~100ms, so doing it per level-up stutters and doing it only on pause left
       the world visibly frozen while the numbers climbed. So: at most one realm
       refresh every 0.4s, oldest first, playing or not. */
    if(!OPEN&&!queue.length&&!active.length&&t-lastSky>0.4){
      const q=W.quarters.find(x=>x.skyStale&&x.island&&HAND.x!==x);
      if(q){ q.skyStale=false; lastSky=t; raiseRealm(q,realmLevelOf(q.shown),playing); }
    }
    /* Queued rebuilds, two a frame — one level-up is ~40 ms of work and a burst
       of them at 16× would otherwise land in a single frame. */
    for(let n=0;n<2&&queue.length;n++){
      const it=queue.shift(); const L=it.queued; it.queued=0;
      if(!L)continue;
      /* Rebuilding what the hand is holding would dispose the group mid-swing.
         It waits its turn; you cannot hold a town for long enough to matter. */
      if(HAND.x===it){ it.queued=L; queue.push(it); continue; }
      if(it.list) raiseRealm(it,L,true);
      else if(L!==it.level) raise(it,L,true);
    }
    /* The transition: everything already standing keeps its exact transform,
       and only the delta animates — new land RISES, new structure BUILDS. */
    for(let i=active.length-1;i>=0;i--){
      const d=active[i], age=t-d.t0; let live=false;
      for(const nd of d.nodes||[]){
        if(nd.done)continue;
        live=true;
        if(nd.mode==='rise'){
          const u=clamp(age/RISE,0,1);
          nd.obj.position.y=lerp(-1.8,0,smooth(u));
          if(u>=1){ nd.obj.position.y=0; nd.done=true; }
        }else if(nd.mode==='build'){