js/mc-parser.js - master - hamster75/Life

js/mc-parser.js
73 строки3 KB
Dmitry Smirnov
large experiment
25 май 2026, 14:59
25 май 2026, 14:599ad2a72
import { join, emptyTree, DEAD, LIVE } from './algorithms/hashlife.js';

// ── Build level-3 node from 8×8 cell array ───────────────────────────────────

function l1(cells, ox, oy) {
  const c = (x, y) => (cells[y] && cells[y][x]) ? LIVE : DEAD;
  return join(c(ox, oy), c(ox+1, oy), c(ox, oy+1), c(ox+1, oy+1));
}

function l2(cells, ox, oy) {
  return join(l1(cells, ox, oy), l1(cells, ox+2, oy), l1(cells, ox, oy+2), l1(cells, ox+2, oy+2));
}

function leafToNode(cells) {
  return join(l2(cells, 0, 0), l2(cells, 4, 0), l2(cells, 0, 4), l2(cells, 4, 4));
}

// ── Parse one leaf RLE line into 8×8 cell array ──────────────────────────────
// Rows separated by '$', '*' = alive, '.' = dead, trailing empties omitted.

function parseLeaf(line) {
  const rows = line.split('$');
  const cells = [];
  for (let y = 0; y < 8; y++) {
    cells.push([]);
    const row = rows[y] || '';
    for (let x = 0; x < 8; x++) {
      cells[y].push(row[x] === '*' ? 1 : 0);
    }
  }
  return leafToNode(cells);
}

// ── Main parser ──────────────────────────────────────────────────────────────

export function parseMC(text) {
  const lines = text.split('\n');
  // nodes[0] = null sentinel (empty, resolved per-context); nodes[1..] = real nodes
  const nodes = [null];

  let rootLevel = 3; // updated as we see non-leaf lines

  for (const rawLine of lines) {
    const line = rawLine.trim();
    if (!line) continue;
    if (line.startsWith('[')) continue; // [M2] header
    if (line.startsWith('#')) continue; // comment

    if (/^[0-9]/.test(line)) {
      // Non-leaf node: "level nw ne sw se"
      const parts = line.split(/\s+/);
      const L         = parseInt(parts[0], 10);
      const childLvl  = L - 1;
      const empty     = emptyTree(childLvl);
      const resolve   = idx => (parseInt(idx, 10) === 0 ? empty : nodes[parseInt(idx, 10)]);
      const nw = resolve(parts[1]);
      const ne = resolve(parts[2]);
      const sw = resolve(parts[3]);
      const se = resolve(parts[4]);
      nodes.push(join(nw, ne, sw, se));
      rootLevel = L;
    } else {
      // Leaf node: 8×8 RLE block (level 3 = 8×8 cells)
      nodes.push(parseLeaf(line));
      rootLevel = 3;
    }
  }

  const root = nodes[nodes.length - 1];
  // Center offset: tree covers [0, 2^level), world origin = tree center
  const half = 1 << (root.level - 1);
  return { root, offsetX: half, offsetY: half };
}