1. A simulation method according to which a simulation apparatus generates a simulant image indicating a cut-out position of a wooden piece in raw wood and a shape of the wooden piece having a predetermined three-dimensional shape at shaping of the wooden piece from the raw wood, the simulation apparatus including a storage unit which stores raw wood information about a shape and a grain pattern of the raw wood and shape information about a shape of a wooden piece to be cut out from the raw wood, the simulation method comprising: receiving an input of a grain pattern which is to appear on a surface of a wooden piece cut out from the raw wood; determining whether a wooden piece can be cut out from the raw wood so that the wooden piece has the three-dimensional shape and a surface showing a similar grain pattern to the received grain pattern, based on the received grain pattern, and the raw wood information and the shape information read out from the storage unit; generating a simulant image indicating a cut-out position and a shape of the wooden piece in the raw wood, when it is determined that the wooden piece can be cut out; and outputting the generated simulant image.