Living Deck: Spatial Card Interaction Prototype

Reality Hack 2026 - USplusplus Team

"Cards come alive in the room - you select by reaching into the swarm."

An XR experience where cards dynamically animate and arrange themselves around the user, and selecting a card is a physical act of capture, not a tap.

This is the official repository for the USplusplus team's project for the MIT Reality Hack 2026 (Jan 23-25, 2026).

Quick Links

• 📖 Docs START HERE - Documentation guide and navigation
• ⚡ Quick Reference - One-page critical path (use this during hackathon)
• 🎯 Immediate Next Steps - Step-by-step from Unity setup to first build
• 📋 Development Plan - Complete 36-hour timeline & architecture
• PRD - Full product requirements document

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This document contains essential Git/Unity setup instructions. Please read carefully before cloning the project.

Project Overview

Problem: Most digital card experiences are static, grid-based, or sequential. Spatial computing allows cards to exist as independent, animated entities in the room, moving, clustering, and responding to user presence.

Core Experience: A deck of cards bursts into motion, filling the space around you. Cards fly, orbit, and drift. You select a card by physically reaching into the swarm. Upon selection, the chosen card freezes and expands while all other cards retreat.

Why Spatial Computing: This experience fundamentally relies on:

• Dozens of objects moving independently in 3D space
• Cards occupying the full volume of the room, not a plane
• Selection based on reach, proximity, and timing
• Motion and depth as core interaction, not decoration

Project Setup

• Unity Version: Unity 6.3 LTS (or Unity 2022.3 LTS)

• Target Platform: Samsung Galaxy XR (Android XR)

• Version Control: Git with Git LFS (Large File Storage)

• Team:

  • Ian - Lead Dev (repo management, Unity setup, hand tracking)
  • Jimmy - Helper Dev (motion systems, card physics, asset integration)
  • Jules - Designer (motion design, UX, timing)
  • Casey - Designer/3D Artist (card meshes, materials, Unity scenes)

• Design Resources:

  • Figma Board: https://www.figma.com/board/fAcBaXzzWVGgT6pFd4iwNA/Hackathon
  • Asset Delivery: Jules and Casey use Figma/Google Drive, Ian and Jimmy handle repo integration

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CRITICAL: First-Time Setup Instructions

To avoid repository corruption and merge conflicts, every team member MUST follow these steps on their machine before cloning.

Step 1: Install Git

If you don't have Git installed, download and install it from git-scm.com.

Step 2: Install Git LFS

Git LFS is required to handle the large assets used in Unity projects.

1. Download and Install: Visit git-lfs.github.com, download the installer, and run it.
2. Initialize LFS for your user account: Open a terminal or Git Bash and run the following command. You only need to do this once per machine.

   git lfs install

   You should see the output Git LFS initialized.

Step 3: Clone the Repository

Now that Git LFS is installed and initialized, you can clone this repository.

git clone https://github.com/Deducer/reality_hack_USplusplus.git

After cloning, git lfs will automatically handle the large files defined in the .gitattributes file. You can now open the project in Unity Hub (making sure to use Unity 6.3 LTS).

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Contribution Workflow

1. Always Pull Before You Start: Before starting any work, make sure you have the latest changes from the remote repository.

   git pull origin main

2. Work on Prefabs and Scenes: To minimize conflicts, try to work on separate prefabs or scenes whenever possible. Communicate with the team on Discord or in-person about who is working on what.
3. Commit and Push Regularly: Make small, atomic commits. Write clear and concise commit messages.

   # See what files you've changed
   git status
   
   # Stage your changes
   git add .
   
   # Commit your changes
   git commit -m "Your descriptive commit message"
   
   # Push your changes to the remote repository
   git push origin main

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Important Technical Notes

Performance Target

• 72fps minimum on Samsung Galaxy XR
• Cap active cards at 52 (standard deck)
• Use object pooling, GPU instancing
• Profile early and often

Development Priorities (In Order)

1. Card spawning and spatial motion
2. Hand-based selection + freeze behavior
3. Non-selected cards reaction (retreat/dissolve)
4. Visual polish and timing
5. Focus state and end experience

Critical Success Criteria

• First-time user can select a card without instruction
• Judge can immediately see why this requires spatial computing
• Experience described as "cards living in the room"

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License

MIT License - See LICENSE file

All source code developed during Reality Hack must be open source (per hackathon rules).

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Thank you for following these guidelines. Let's build something amazing! 🚀