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# Bitangent

The geometric bitangent vector of the currently-processed data in a given coordinate space.

## Parameter Types

|Input  |Type  |
        |-------|------|
        |`Space`|String|
        |`Index`|Int32 |

|Output|Type    |
        |------|--------|
        |`Out` |Vector3f|

## Parameter descriptions

- `Space`: The space in which the shader defines the bitangent vector. Defaults to `object`.
- `Index`: The index of the texture coordinates that the node computes the tangent against. Default is `0`.

## Discussion

Valid values for the `Space` parameter include:

- `model`: The local coordinate space before the shader applies any local deformations or global transforms to the geometry.
- `object`: The local coordinate space after the shader applies local deformations, but before it applies global transforms to the geometry.
- `world`: The global coordinate space after the shader applies both local deformations and global transforms to the geometry.

---

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