Skip 30-Minute Keystone Fiddling & Blurry Ruler Guessing at Your Table.
Point your phone at 4 calibration cards or a printed sheet once. Bags of Folding locks any battle map, animated video, or VTT view to an exact 1-inch (25.4mm) miniature grid—then shuts off your camera so 100% of GPU power drives 60 FPS Fog of War and spell effects.
Advanced Media, Voice, NFC & Shader Controls
CV Web Worker & Dual-Node Sync
Runs zero-copy Transferable frame analysis off the main thread and immediately tears down camera tracks once 15 consecutive frames yield σ < 0.5 mm.
How It Works in 3 Steps
- Place Your Target: Drop a $1 dollar-store 22" × 28" poster board, printed US Letter sheet, or 4 calibration cards on your table.
- Run 15-Frame Auto-Lock: Launch the Display Window on your projector/HDMI monitor and scan once from your handheld controller.
- Play at Exact 1" Scale: Your camera turns off automatically while you pan, zoom, paint Fog of War, and cast Chained Fireballs at 60 FPS.
Frequently Asked GM Questions
Will every square really measure 1 inch (25.4 mm) when my projector is angled on a shelf?
Yes. The inverse 3×3 homography solver (`H⁻¹`) runs per fragment on the GPU, correcting trapezoidal keystone distortion and locking 1 grid square to `25.4 mm × 25.4 mm` on the physical surface.
Does my phone camera stay on and drain battery during a 4-hour session?
No. The instant 15 consecutive frames settle below `0.5 mm` variance, `TEARDOWN_VISION` stops every `MediaStreamTrack` and ends WebXR. You can trigger a 2-second quick recalibrate any time if the projector bumps.
What happens outside the poster board or map edges?
The GLSL fragment shader clamps everything outside `[0, tableBoundsMm]` to pure black `#000000`, preventing projector light spill onto players or floors.