| 摘要 |
PURPOSE:To rapidly form a highly clear image in accordance with the optional movement of a substance by finding out OR operation of two-dimensional digital images and extracting an area requiring hidden face erasing processing on the basis of the OR result. CONSTITUTION:A coordinate conversion means 111 forms two-dimensional graphic data obtained before and after change corresponding to a drawing plane from three-dimensional graphic data 101, 102 obtained before and after a change due to the movement of a substance to be drawn. On the other hand, an image drawing means 112 forms two-dimensional digital images 123, 124 obtained before and after the change corresponding to the data 121, 122. An image operating means 113 finds out OR operation between the images 123, 124 obtained before and after the change and extracts an area 131 required for the hidden face erasing processing. Since only one hidden face erasing processing is executed, the processing time can be shortened and the drawing processing is speeded up as a whole. |
