PURPOSE: To correct a shape by means of a parametric function while the shape inputted by means of a sketcher function is preserved without destroying the shape which an operator images by collectively executing parametric deformation on the whole drawn shape.

CONSTITUTION: A graphic is generated by using the sketcher function of a graphic processor. After a graphic generation processing is terminated, graphic data storage processing means 101 and 201 store graphic data into a graphic data storage area. A dimension on the graphic element is added and dimension storage processing means 102 and 202 store the added dimension in a dimension storage area. The operator selects whether the whole generated graphic shape is corrected or only the designated graphic element is corrected by judgment. When the correction processing of the whole shape is selected, shape data of the graphic element, which is drawn in a graphic generation procedure, is changed and data is stored in a new graphic data storage area. A new graphic plotting processing means 107 replots the whole graphic shape in accordance with stored data.