To prevent a fixed graphic from being erased from a screen by first plotting an omitted graphic in the next scene by providing a means for inquiring the identifier of the graphic omitted in plotting in the middle of one scene while adding the identifier to the graphic to be plotted.

After the end of the plotting processing of one scene, a user can inquire a graphic display priority inquiry information table 56. Inside the table 56, in addition to graphic display priority information, a graphic identifier 52 and a plotting flag 53 for showing whether it is a non-plotted graphic or not are stored. Since there is the case of returning plural sets of graphic display priority inquiry information, the size of a main table has a variable length. After one scene is plotted, the user acquires main table information and can know the graphic to be first plotted in the next scene. Concerning such animation display, the graphic, which can not be plotted in the preceding scene, is plotted in the next scene without fail.