1. A method of generating a three-dimensional (3D) shape by specifying a boundary between materials, comprising: acquiring numerical data of a boundary line of a first two-dimensional (2D) shape in a plane; generating a second 2D shape by moving the first 2D shape in a direction intersecting the plane based on the acquired numerical data specifying a shape of the boundary and by deforming the first 2D shape; and configuring a solid based on data of the generated second 2D shape.