IMAGE PROCESSING DEVICE AND IMAGE PROCESSING METHOD

According to the image processing method, when the number of shadow polygons existing between a depth position of pixels of ordinary polygons subject to shadowing and an infinite position is counted and that number is an odd number, those pixels are unconditionally judged to be positioned inside a region of shadow volume. Therefore, regions to undergo shadowing can be efficiently detected by judging whether the number is an odd number or an even number at all pixel positions.