// Seeded worlds, no storage round-trip (saves quantize heat and land flying grains).
function perfScene(name, w, h) {
  GAME.running = false;
  // Match a fresh page: generation retains the power scheduler and weather random stream.
  nextPowerBuild = 0; WS = 0x1b873593 | 0;
  for (const key of Object.keys(stats)) stats[key] = 0;
  generateWorld(424242, w, h, null);
  for (let k = 0; k < 600; k++) simTick();
  if (name !== 'settled') {
    const x0 = Math.max(8, (W / 4 - 100) & ~3), y0 = Math.max(16, Math.min(H - 176, (surfY[Math.max(8, W / 4 | 0)] - 100) & ~3));
    for (let y = y0; y < y0 + 160; y++) for (let x = x0; x < x0 + 200; x++) {
      setCell(y * W + x, y >= y0 + 144 ? STONE : EMPTY, AMB[y], 0);
      bgm[y * W + x] = 0;
    }
    bot.x = x0 + 98; bot.y = y0 + 50;
    if (name === 'factory') {
      // Furnace and hopper from experiments/factory_cost.js, with a screw/filter line.
      const mx = x0 / 4 + 3, my = y0 / 4 + 16;
      const place = (code, v, x, y, extra) => {
        const error = placeBlock(code, v, x, y, true, extra);
        if (error) throw Error(`factory ${x},${y}: ${error}`);
      };
      for (let by = my; by < my + 4; by++) for (let bx = mx; bx < mx + 4; bx++) {
        if ((bx > mx && bx < mx + 3 && by > my && by < my + 3) || (by === my && bx === mx + 2)) continue;
        place(BP_WALL, RSTONE, bx, by);
      }
      for (let y = (my + 1) * 4 + 3; y < (my + 3) * 4; y++) for (let x = (mx + 1) * 4; x < (mx + 3) * 4; x++)
        setCell(y * W + x, (x + y) & 3 ? COAL : CUORE, 700, 0);
      for (let x = mx + 8; x < mx + 25; x++) place(BP_BELT, 1, x, my + 5);
      for (let x = mx + 25; x < mx + 30; x++) place(BP_SCREW, 1, x, my + 4);
      for (let x = mx + 30; x < mx + 40; x++) place(BP_FILTER, 128, x, my + 5, { m: [SAND], inv: 0 });
      // Two full silos keep both materials flowing for the entire real run.
      for (const [dx, material] of [[9, SAND], [33, CUORE]]) {
        const silo = addMachine('silo', mx + dx, my - 2, 0);
        silo.sm = material; silo.sn = SILO_CAP; silo.open = true;
      }
      // Start with a loaded line, rather than timing its initial travel delay.
      for (let x = (mx + 8) * 4; x < (mx + 40) * 4; x++)
        setCell(((my + 5) * 4 - 1) * W + x, x & 3 ? SAND : CUORE, AMB[(my + 5) * 4 - 1], 0);
    } else {
      for (let y = y0 + 100; y < y0 + 144; y++) for (let x = x0 + 12; x < x0 + 188; x++)
        setCell(y * W + x, y < y0 + 114 ? WATER : MAGMA, y < y0 + 114 ? 20 : 1450, 0);
    }
    for (let k = 0; k < 60; k++) simTick();
  }
  enterGame(); GAME.paused = true;
  SET.fog = false; SET.autosave = 0; SET.cameraLead = false; SET.shake = false;
  SET.fpsCap = 0; SET.showPerf = false;
  document.querySelectorAll('.card, .toast').forEach(e => e.remove());
  R.particles.length = 0;
  snapCamera(); acc = 0;
  return perfState();
}
function perfState() {
  let a = 0, h = 0;
  for (let c = 0; c < NCH; c++) { if (awake[c]) a++; if (hot[c]) h++; }
  return { tick, awake: a, hot: h, chunks: NCH, moved: stats.moved,
    flyers: flyers.length, silos: machines.filter(m => m && m.type === 'silo').map(m => ({ material: m.sm, grains: m.sn, pouring: tick - m.pourT < 10 })), camera: [R.camX, R.camY], bot: [bot.x, bot.y] };
}
function perfView(look, zoom) {
  SET.look = look; SET.zoom = zoom; SET.lighting = 'full';
  resizeRender(); snapCamera();
  for (let k = 0; k < 5; k++) { R.frame++; drawWorld(); }
  if (look === 'smooth' && (!R.smoothOn || (!R.gpuOn && !SM.ok))) throw Error('Smooth look unavailable: ' + SM.why);
  return { grains: R.bw * R.bh, buffer: [R.bw, R.bh], scale: R.gpuOn ? 1 : SM.scale };
}