这个新的贴图坐标被用来索引一般的材质贴图和其他用在表面上的贴图。

The new texture coordinate is used to index a regular texture map and any other maps applied to the surface.

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但是，当你看着一个实际表面而不是带材质贴图的多边形的时候，你将会看到的是点b。

However, if you were viewing the actual surface instead of a texture mapped polygon, you would see point B.

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当使用材质贴图在光滑的多边形上表现一个粗糙的表面时，那个表面看起来像是平坦的。

When a texture map representing an uneven surface is applied to a flat polygon, the surface appears to get flattened.

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