PURPOSE: To efficiently correct the shape mode such as a three-dimensional model by detecting the extent of interference between shape models displayed on a screen, and indicating the extent of interference with a display or voice.

CONSTITUTION: A processing part 1 after generating the three-dimensional shape model according to operator's indications registers the three-dimensiona1 shape model as component data in a component data memory 5. Then, whether or not the three-dimensional models displayed on a display device 2 interfere with each other, is detected. When it is known that they interfere with each other, the extent of the interference, concretely, the rate of the extension of the range of the interference to the three-dimensional shape models is detected, color data corresponding to the extent of the interference is selected in a color data memory 4, and the range of the interference between the three-dimensional shape models is painted in the color. Further, voice data on the contents corresponding to the extent of the interference are selected in a voice data memory 6 and the voice of the contents corresponding to the voice data are outputted from a speaker 3.