Arcane Tycoon — Heroes & Magic theme park tycoon game

Complete browser game inspired by OpenRCT2 with fantasy twist:
- Custom roller coaster designer with physics-based ratings + on-ride POV
- 10 animated rides, 7 shops, 16 scenery items, path network & guest AI
- Heroes guild vs monster invasions (5 classes, XP/gear/bosses)
- Magic spell system (8 spells), research tree, economy/marketing/loans
- Day-night cycle, weather, park rating, awards, 4 scenarios
- Save/load slots + autosave, procedural WebAudio SFX/music
- Isometric canvas renderer, minimap, diagnostics overlay
- Test suites: smoke(13), linkcheck, inputcheck, framecheck, rendercheck, flow

js/game/research.js

@@ -0,0 +1,32 @@
+// ============ research.js — unlock tree ============
+import { UNLOCKS, RESEARCH_TRACKS } from '../core/config.js';
+
+export function isUnlocked(state, key) {
+  if (state.sandbox) return true;
+  return state.research.unlocked.includes(key);
+}
+
+export function canBuy(state, u) {
+  if (isUnlocked(state, u.key)) return { ok: false, why: 'owned' };
+  if (state.research.rp >= u.rp) return { ok: true };
+  return { ok: false, why: 'rp' };
+}
+
+export function buyUnlock(state, key) {
+  const u = UNLOCKS.find(u => u.key === key);
+  if (!u) return false;
+  const chk = canBuy(state, u);
+  if (!chk.ok) return false;
+  state.research.rp -= u.rp;
+  state.research.spentTotal += u.rp;
+  state.research.unlocked.push(key);
+  state.toasts.push({ kind: 'good', title: 'Research complete!', text: `${u.label} is now available to build.` });
+  return true;
+}
+
+export function unlocksByTrack() {
+  const out = {};
+  for (const t of Object.keys(RESEARCH_TRACKS)) out[t] = [];
+  for (const u of UNLOCKS) (out[u.track] || (out[u.track] = [])).push(u);
+  return out;
+}