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第七章 消除隐藏线和隐藏面的算法 PowerPoint PPT Presentation


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第七章 消除隐藏线和隐藏面的算法. 消隐 面消隐 线消隐 三维形体表示为 多边形 表面形集合 投影约定为沿着 z 轴正向的 正交 投影 消除隐藏面算法: 图象空间算法 客体空间算法. 图象空间算法对显示设备上每一个可分辨 象素 进行判断,看组成物体的多个多边形表面中哪一个在该象素上可见,即要对每一象素检查所有的表面。 客体空间算法把注意力集中在分析要显示 形体 各部分之间的关系上,这种算法对每一个组成形体的表面,都要与其它各表面进行比较,以便消去不可见的面或面的不可见部分。. 第一节 线面比较法消除隐藏线. 多面体的面可见性

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第七章 消除隐藏线和隐藏面的算法

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