Rangoli Rush

Inspiration

In India, homes greet guests with rangoli: patterns of coloured powder drawn on the floor at Diwali, weddings and the start of a new season. You pinch powder between thumb and finger and let it trickle into a petal. That pinch is the most natural gesture on Quest hand tracking, so I asked what rangoli would feel like if your living-room table became the courtyard floor.

What it is

Rangoli Rush is a seated, hands-only mixed-reality puzzle. A chalk-outlined rangoli appears on a slate tile in front of you with brass bowls of powder at your sides. Pinch inside a bowl to scoop powder, brush over the petal that needs that colour, or flick your wrist to throw powder across the board. Quick fills build a combo whose notes climb a Bhupali pentatonic scale. A 30-second tutorial teaches pinch, brush and flick, then three levels ramp from two to five powders. A Daily Rangoli gives everyone the same new pattern each day and keeps a local streak.

How I built it

WebXR on the Immersive Web SDK (IWSDK 1.1, three.js), as an immersive-ar session so the rangoli sits on your real table under passthrough, with a procedural dusk courtyard as fallback. Pinch is detected from raw hand-joint poses with hysteresis; flicks use the hand's peak velocity in the ~150 ms before release; gaze plus pinch selects at a distance. All meshes, particles and sound (WebAudio) are procedural, so nothing downloads at start. Tested end to end in IWER with emulated Quest 3 hands.

Hand interactions

Poke buttons or look and pinch. Pinch in a bowl to scoop, or look at a bowl and pinch in the air to pull powder. Hold the pinch and brush to fill (red flash on wrong colour). Flick to throw; release slowly to drop. Hands only, seated, within ~0.6 m; controllers optional. Shape glyphs for colour-blind players.

What's next

Kolam, mandana and alpana pattern families, a festival calendar, a shared two-person family rangoli in co-presence, spatial anchors that remember your table, a relaxed no-timer mode, then a Horizon Store PWA release in Q1 2027.

Built With

• github
• iwsdk
• three.js
• typescript
• vite
• webaudio
• webxr