Tangram

Tangram is the centuries-old Chinese dissection puzzle: one square cut into seven pieces — two large triangles, one medium triangle, two small triangles, a square and a parallelogram — that can be rearranged into an endless gallery of figures. This digital version keeps the geometry exact: the pieces are the true tangram set, cut from a verified dissection of the 4×4 square, and they begin each round assembled as that original square on the right of the board, just as a physical set would be handed to you.

Six silhouettes are provided — Boat, House, Rocket, Fish, Candle and Cat — plus an unlimited free-play sandbox. Pieces drag smoothly, snap to a fine quarter-unit grid when dropped, rotate in exact 45° steps, and the parallelogram can be flipped, which matters because it is the only chiral tangram piece: some silhouettes are impossible without its mirror image. Solution checking is done by point sampling rather than exact placement matching: the game measures what fraction of the silhouette your pieces cover and what fraction of your pieces lies inside the outline, and compares both against what is geometrically achievable, so any genuinely good arrangement passes — not just one memorised layout.