Use these enum flags to specify which elements of a vertex to compress.
默认设置：通常需要实现高精度，因此不会压缩位置和 TexCoord1。其他内容都会进行压缩，以节省内存和带宽。
| None | Vertex compression disabled. |
| Position | Position compression enabled. |
| Normal | Normal compression enabled. |
| Tangent | Tangent compression enabled. |
| Color | Color compression enabled. |
| TexCoord0 | Texture coordinate 0 compression enabled. |
| TexCoord1 | Texture coordinate 1 compression enabled. |
| TexCoord2 | Texture coordinate 2 compression enabled. |
| TexCoord3 | Texture coordinate 3 compression enabled. |