How To Play

1. Select a numbered piece. The selected piece appears below the silhouette until you move it onto the board.
2. Drag it with a mouse or touch. Use the arrow buttons for precise quarter-unit moves.
3. Rotate in 45° steps or flip the piece. Arrange all seven pieces to cover the silhouette without overlap.

Standard seven pieces

The set contains two large right triangles, one medium right triangle, two small right triangles, one square and one parallelogram. Together they have the area of the starting square. Pieces cannot be resized.

Keyboard controls

Keys 1–7 select a piece. Arrow keys move it. R rotates clockwise by 45° and F flips it. The visible turn-back button rotates counterclockwise. All touch controls stay available.

Guides and fitting

Show piece guide outlines an intended position for the selected piece. It does not move the piece. Once its orientation matches and it is very close, the piece snaps precisely into place. Matching triangles can be exchanged. Any valid coverage is accepted, not just one stored arrangement.

The Fitted count includes pieces fully inside the silhouette with no overlap. Every piece must fit before you win. Seven original silhouettes are available from the selector.

Undo and replay

Undo move restores the last completed drag, move, rotation or flip. An interrupted drag is cancelled. Restart shape returns all pieces to the tray after confirmation if unfinished. After a win, Next silhouette opens the next shape; a previously completed next shape starts again.

Rule reference

The standard seven-piece set was checked against Mathigon’s official Polypad guide. Foldgrove’s silhouettes, colours, controls and wording are original.