If no cascaded shadow maps were used, the entire shadow distance (still 50 units in our case) must be covered by the shadow texture uniformly. Hard shadows would look like this with no cascades.

如果不使用级联阴影，整个阴影距离(仍然是50单位)内，阴影纹理均匀的覆盖。没有级联，硬阴影看起来像这样。

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For Directional lights Unity can use so called Cascaded shadow Maps (alternatively called "Parallel Split shadow Maps") which give very good shadow quality, especially for long viewing distances.

对于平行光，Unity可以使用级联阴影贴图(或成为平行分割阴影贴图)有很好的阴影质量，特别是远距离观看。

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