Edge matching

Edge matching

Choose a preset or edit the prototype, set the maximum size and Generate. Plain edge labels match equal labels; a+ matches a−, never a+. Every coincident contact must match, with full edges and no interior overlap.

Edge labels contains one input for each polygon side in vertex order. Coordinates edits the selected vertex; expressions such as sqrt(5)/2 are accepted. Drag vertices or polygons, click an edge to insert a vertex. With canvas focus, Delete removes a vertex and Enter ends drawing. Ctrl/Meta + wheel zooms; a plain wheel scrolls.

The solver tries quarter-turn rotations greedily, without backtracking. Stopped growth does not prove that no larger tiling exists. Grid controls drawing/snapping, not the placement search. Edits clear the result; resize redraws cached tiles. PNG exports the current patch.

Simple polygons with 3–64 vertices, 1–300 tiles and labels up to 32 characters. Geometric comparisons use relative floating-point tolerances; extremely thin features may be unresolved. Settings restore without automatic growth.

Choose Draw your own for a blank grid; click at least three vertices and press Enter to finish.