| 摘要 |
<p>PURPOSE: To form wire frame graphic display having no hidden line through the computer processing of a triangle by comparing the Z value of a point on the side of each polygon with a value stored at the storage position of a correspondent depth buffer and separating that point from the other points. CONSTITUTION: The Z value of a display point belonging to the side of a visible polygon is calculated and when that point is positioned closer to a viewpoint rather than the Z value stored in a depth buffer 28, the Z buffer 28 is updated by the reserved Z value of ZCLOSE or the like. Next, a Z value concerning each point on the triangle decomposing the polygon to be processed is calculated. When that value is positioned much closer to the viewpoint, the depth buffer 28 is updated by that value and a background color is written in a frame buffer 14. Then, the Z value of the display point belonging to the side of the polygon is calculated again. When the value of the depth buffer is equal with the ZCLOSE or the calculated value expresses the position closer to the viewpoint, the depth buffer 28 is updated by the calculated value and a foreground color is written in the frame buffer 14.</p> |
