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"Displacement maps_位移映射"和"bump maps_凹凸映射"的区别在那？
"Displacement maps_位移映射"在顶点和片断级别真正的改变了几何位置，换句话说，使用"Displacement maps_位移映射"物体的几何轮廓被真正改变了。
作为对比，"bump maps_凹凸映射"并没有改变物体的几何位置，而是改变了顶点的法线。所以，只有在光源位置改变或视点改变时才起作用。对于一张静态的截图，很难说它是基于"Displacement maps_位移映射"还是"bump maps_凹凸映射"。
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What's the difference between displacement maps and bump maps?
Displacement maps actually change geometric position at the per-vertex or per-fragment level. This means that object silhouettes actually change, based on the displacement map.
In contrast, bump maps keep the geometric position the same, but perturb the normal. Therefore, bump mapping is useful only when lighting changes or when the viewpoint moves (in the case of specular highlights). Given a static screenshot, it is often difficult to tell if a surface is bump-mapped or displaced.
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发表于 2006-12-18 12:08:00