[ brush ]
[ shape ]
select a number
[ tools ]
Painting
- Click a number (1–20) in the palette to select a brush.
- Left-click any empty cell to paint it.
- Right-click a painted cell to erase it. Brush auto-switches to the erased number.
- Counters show have/need. Green = complete, red = over-placed.
Locking
- Right-click a palette button to lock/unlock. Locked numbers (green border, “L”) survive “Clear All”.
Shape Preview
- When a brush has cells on the grid, the shape preview appears.
- Click a cell in the preview to set the anchor (pink border).
- Cycle orientations with Scroll, Q/E, or the numbered buttons.
Stamp Mode
- Click Stamp to activate.
- Set PAINT AS with ± to stamp a shape as a different number (e.g. use 12-omino shape to stamp as 13).
- Hover over the grid to preview placement.
- Click to place.
- Right-click or Esc to exit.
Containment
- When both N and N+1 are fully placed, a check runs automatically.
- ✓ = contained. ✗ = invalid.
Tools
- Export / Import — save/load grid state as JSON.
- Clear All — removes all non-locked cells.