📖 About

Ever walked past a wall of furnaces and wondered which one has your iron in it? Vanilla gives you two dark, empty slits and no answers — the only way to know is to open every single one.

Furnace Peek turns the furnace's front face into a window. The two dark openings show what's actually inside: the item being smelted appears through the top opening, and the fuel appears through the bottom one — rendered right on the block, live, with zero clicks.

It's a purely visual, client-side mod. Nothing about smelting, fuel burn time, recipes, or block behavior changes — the furnace just stops keeping secrets.

🖼️ States

Smelting preview	Fuel preview	Lit & burning
Top opening shows the input slot	Bottom opening shows the fuel slot	Red glow + flame, arch intact

✨ Features

• 🔍 At-a-glance previews — the smelting item shows in the top opening, the fuel item in the bottom one, using the items' own icons.
• 🔥 Living lit state — while the furnace burns, a warm red glow blends into both openings (pixel-exact, following the opening's natural arch shape), with an animated flame flickering behind the fuel.
• 🧊 Honest unlit state — no burn, no effects: icons show in their natural colors. Empty slot? The opening stays exactly vanilla-dark.
• 📚 Stack-size hints — 1 item shows one icon, 2 show a pair, 3+ show a small pyramid stack.
• 🪨 Still unmistakably a furnace — nothing floats, nothing sticks out. Items sit inside the openings, tucked behind the furnace's own frame; the block silhouette and textures are untouched.
• ⚡ Featherweight — a handful of quads per visible furnace, throttled data refresh. Furnace walls welcome.
• 🔄 Live updates — swap the input, top up fuel, or let the fire die: the face updates within a fraction of a second.

❓ FAQ

Does it work on multiplayer servers? Currently the previews appear in singleplayer (and worlds you host). On dedicated servers the mod stays quietly dormant — furnace contents simply aren't sent to clients by vanilla. Server-side support is on the roadmap.

Smoker and Blast Furnace? Out of scope for this first release — regular furnaces only. The same treatment for their cousins is a natural follow-up.

Does it show the output slot? No, by design. Only the two input-side slots (smelting + fuel) are previewed.

Will it lag with a big furnace array? No. Each visible furnace costs a few quads and a cached, rate-limited data lookup (one refresh per ~200 ms per furnace, only while visible).

Does it change gameplay? Zero. No mechanics, recipes, burn times, or block behavior are touched — it's rendering only.

🧭 Roadmap

• Server-side sync for dedicated-server previews
• Smoker & Blast Furnace support
• Config (toggle glow/flame/stack hints)

📜 License

CC0-1.0 — public domain. Source on GitHub.