APPARATUS AND METHOD FOR DRAWING THREE DIMENSIONAL GRAPHICS BY CONTROLLING α VALUE BASED ON Z COORDINATE VALUE

摘要

In the three-dimensional graphics drawing apparatus, a color register has an alpha register in which a Z-coordinate value of an object is set as its alpha value. A drawing unit draws the object based on coordinate data stored in a coordinate register and color data stored in the color register. Accordingly, the degree of transparency of a drawing object that is closer to the front increases, and a portion that is hidden behind the drawing object becomes apparent. Visibility is thus increased.