语法：

vertex_format_add_normal();

返回：

N/A（无返回值）

描述

Tell GameMaker Studio 2 to accept surface normal data (nx, ny and nz) as part of the new vertex format being created.

例如：

vertex_format_begin();
vertex_format_add_textcoord();
vertex_format_add_normal();
my_format = vertex_format_end();

The above code will create a new vertex format with just texture and surface normal values and then store the format id in the variable "my_format".