可以看出，由于使用了Ajax，视图层的脚本编写量增加了，从而导致三个明显缺陷。

You can see that the amount of scripting code in the view layer increases with the use of Ajax, causing three significant drawbacks.

youdao

按照下面的样子，添加一个图层蒙版，这样可以给整个画面增加整体光的对比度，画面看起来会更好一些。

Add a layer mask to this layer as shown below, this will create a better lighting contrast for the hand and make this overall image look better.

youdao

我需要两个图层是为了精确地控制两个范围小石子的分布——从边石到远距离和第二个从逐渐增加的石子密度到边石。

I needed two layers to precisely control small stones distributing with two ranges - from curbs to distance and the second to increase density of stones close to the curbs.

youdao