Cast in Bidri Metal: Four Ancient Karnataka Board Games, Reborn in 3D

Before Ludo, before Snakes & Ladders left the subcontinent and came back Anglicised, our grandmothers drew boards in rice-flour on the courtyard floor and played games older than most kingdoms. This is an attempt to give four of Karnataka's own games a home that honours where they came from — and looks good enough to keep on your phone.

I'm Naveen Gopalakrishna — an AI Global Black Belt at Microsoft, a compulsive builder after hours. This #AI4Good build is four games shipped together, each its own free web app and Android APK:

The games, and where they come from

None of these are inventions. They're games with centuries — sometimes millennia — of continuous play across South India.

• Saalu Mane Ata (Nine Men's Morris) is a mill game — three nested squares, nine seeds a side. Form a connected line of three ("a mill") and you break a rival seed. Pure strategy, no dice: the same family of game scratched into the stone floors of temples at Aihole. A game of foresight.
• Aadu Huli (Goats & Tigers) is an asymmetric hunt on a triangular board — a few tigers leap to capture goats, while a herd of goats tries to hem the tigers in until they cannot move. The South Indian cousin of Bagh-Chal.
• Chowka Bara (Ashta Chamma) is a race game played with cowrie shells for dice on a cross-and-circle board, with safe squares. The ancestor Ludo forgot.
• Alaguli Mane (Pallanguzhi) is a mancala — two rows of pits, seeds sown counter-clockwise, pits of four captured. No luck, just counting ahead. The carved wooden board is a genuine heirloom in Kannada and Tamil homes.

Each game ships with multiple "worlds" — a Realistic heritage board, an Original glowing-3D reading, a Modern interpretation, sometimes a Fable world — and the one this post is really about.

The Bidri world — the reason this build exists

The spark for the whole project was a single question: what would these games look like if a master craftsman of Bidar made them?

Bidriware is a 14th-century metal craft from Bidar, Karnataka. A zinc-and-copper alloy is cast, engraved with floral and geometric tarkashi patterns, inlaid with pure silver wire, then blackened with a special soil from the Bidar fort — a soil that darkens the alloy to deep matte black but leaves the silver brilliant. The result is unmistakable: jet-black metal, glowing silver inlay. A GI-tagged craft, and one of the most striking in the world.

So every game got a bespoke Bidri board — not a generic skin, but a mat whose inlay is designed around that game's geometry:

How we matched real artisan work

Getting AI-generated art to actually read as Bidri — and not as "generic ornate black-and-gold" — took a tight loop:

1. Study first. Real Bidri is matte black, not glossy, the inlay is silver, not gold, the motifs are floral tarkashi and geometric bands, and the craft lives in the contrast. Those became hard constraints.
2. Prompt to the constraints. Every render was pushed toward "near-black blackened-brass ground, brilliant pure-silver inlay, delicate floral tarkashi engraving, museum-quality metalwork, soft studio light with rich reflections" using Azure gpt-image-2. Gold only as a thin rim highlight.
3. Align the board to the mat. The generated ornament had to sit around the playable geometry — central design centred on the board, surrounding tarkashi filling the field, the way a craftsman composes a real tray. The mat and a seamless table tile were rendered as a set.
4. Iterate on light & reflection. Several passes went purely into how the silver catches light and how the black holds shadow, until each board looked photographed, not textured.

The same pipeline produced each game's app icon — this game's own board, cast in Bidri. The Bidri work was distilled into a reusable "Bidri style" skill so the look stays consistent across future builds.

How it was built

The whole suite is deliberately boring where it counts so it can live forever for free:

• Pure static, mobile-first, Kannada-first. No backend, no accounts, no tracking. Each game is a folder of HTML/JS/assets on GitHub Pages. Kannada is the first language, English second.
• 3D in the browser. A shared Three.js core (game3d) renders boards, pieces and worlds, tuned for a mid-range phone. Each game is a thin ruleset on top.
• Four games, one drift-locked core. ~36 shared modules stay byte-identical across all four, enforced by a custom rc-gate that fails the build on any drift and runs the full unit-test matrix (668 tests: AH 206 · AM 161 · CB 152 · SMA 149), i18n coverage, JSON-schema contracts, language/voice-pack freshness, and an asset budget.
• Six languages, packaged. Kannada + English core; four more ship as downloadable text & voice packs (an "asset diet" with a default-core build that fetches optional packs on demand).
• Narration via Azure Speech neural voices, later repacked to cut size.
• APKs from the same web build. Capacitor wraps each web/ folder; GitHub Actions builds a debug APK on every release (JDK 21, cap add android, gradlew assembleDebug) and attaches it automatically. Push to main → Pages redeploys; publish a release → the APK builds itself.
• Art & icons: Azure gpt-image-2. Everything is open source.

What I learned

• Constraints make AI art authentic. "Ornate Indian" gets you tourist-shop clip-art. "Matte-black blackened alloy, pure-silver tarkashi, no gold except a rim highlight" gets you something a Bidar artisan would recognise. Research the craft, then encode it as non-negotiables.
• A drift gate is worth more than a test suite alone when shipping four near-identical apps. The most valuable script in the repo is the one that refuses to let the four codebases diverge silently.
• Ship the culture first, the translation second. Kannada-first (not "English with a toggle") changed how the whole UI reads.
• Static + Capacitor is a superpower for heritage software. One web/ folder becomes a free website and an installable app, zero servers — exactly right for something meant to outlast any hosting bill.
• A tiny asset budget forces good decisions. Packing optional languages/voices and fetching on demand kept the base app small without cutting features.

Try it

Free, offline, no account, open source:

• Saalu Mane Ata — play · APK · source
• Aadu Huli — play · APK · source
• Chowka Bara — play · APK · source
• Alaguli Mane — play · APK · source

If you have grandparents who played these on a courtyard floor, show them the Bidri board. That reaction is the whole point.