What materials are the Custom Alpha templates suitable for? What are the special parameters?

Custom Alpha material templates specifically used to create hollow effects.

The only special parameter of this template is the "Opacity Map" parameter. But there is a slight difference with the "Opacity Map" in the Cloth material template. There is no semi-transparent effect here, the material is either completely preserved or completely hollow. Therefore, here it is recommended to use only black and white map to control the hollow effect. White is the material that is preserved, and black corresponds to the hollow position.

In the range of 0~255, Opacity Map gray value greater than 157, the corresponding material will be retained, and gray value less than 156, the corresponding material will be hollowed out.