Texture coordinates are named (s, t) in order to distinguish them from the (x, y) used for vertex positions (in literature, (u, v) is commonly used instead).

将纹理坐标命名为(s, t)是为了与用于表示顶点位置的(x, y)区分开来(从文字角度来讲，(u, v)更为常用)。

youdao

His approach allowed the district court in McCollum to distinguish, rather sharply, old standbys such as Wickard v.

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