In contrast, XML data is "nested", and its depth of nesting can be irregular and unpredictable.
比较而言，XML数据是“嵌套的”，并且其嵌套深度可以是不规则且不可预测的。
2
Light and Shadow - Bright objects appear closer than dark objects. Light and from irregular surfaces also give depth cues.
光与影-明亮的物体看起来比暗物体更近。光线和不规则表面也会产生深度暗示。
3
This paper introduces a method for calculating the contact point, contact normal and penetration depth in collision detection of irregular objects expressed by triangle mesh.