However, Occlusion Culling is more complex, some needs large memory, others has long runtime, anther is suit for the fixed type of the object. 而遮挡裁减算法就比较复杂,一些遮挡裁减算法占用内存大,有些算法的处理时间较长,而其它算法则仅针对某些特定的物体类型。
It can completely remove the isolated small fragments which around the structure of the interest. Secondly, when the grey values of the interest object relatively large changes, a fixed iso-surface is not suitable for use in approximating the boundary surface of the interest object. 能完全去除感兴趣结构周围的孤立细小的碎片。其次,当感兴趣结构边界面上离散采样点灰度值变化比较大,很难用一个具体的等值面对其进行逼近。