This enum is used to build a bitmask for controlling per-channel vertex compression.
Default settings: Position and TextureCoordinate1 are uncompressed because high precision is usually desired. The rest of the channels are compressed to save memory and conserve bandwidth.
| kPosition | Position. |
| kNormal | Vertex normal. |
| kColor | Vertex color. |
| kUV0 | Texture coordinate channel 0. Usually used for Albedo texture. |
| kUV1 | Texture coordinate channel 1. Usually used for baked lightmap. |
| kUV2 | Texture coordinate channel 2. Usually used for realtime GI. |
| kUV3 | Texture coordinate channel 3. |
| kTangent | Tangent. |