# Unwrap UV

> Use this feature to unwrap UV coordinates on 3D meshes, enabling efficient texture mapping and reducing distortions in the unwrapped 2D representation.

API function: [algo.unwrapUV](/asset-transformer-sdk/2026.4/api/python/algo_functions.md#unwrapuv)

Considering a set of UV islands (defined either by existing UV coordinates or by lines of interest over the mesh surface), this function generates UV coordinates by flattening each 3D surface patch corresponding to an island onto the Euclidean plane while minimizing a distortion criterion between both 3D and UV spaces.

| ![](/api/media?file=/asset-transformer-sdk/media/images/unwrap-uv/cube3d.png) | ![](/api/media?file=/asset-transformer-sdk/media/images/unwrap-uv/cube-unwrap-arap.png) | ![](/api/media?file=/asset-transformer-sdk/media/images/unwrap-uv/cube-unwrap-abf.png) |
| ----------------------------------------------------------------------------- | --------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------- |
| An open cube to unwrap                                                        | Isometric unwrapping(edge length preserving)                                            | Conformal unwrapping(angle preserving)                                                 |

> **Important:**
>
> This function only unwraps UV islands, but doesn't pack texture coordinates into the unit square.
> To do so, you must call [algo.repackUV](/asset-transformer-sdk/2026.4/api/python/algo_functions.md#repackuv) afterwards.

## Parameters

### Occurrences

List of occurrences to process.

### Method

Determines the type of solver used for unwrapping (using the enum [algo.UnwrapUVMethod](/asset-transformer-sdk/2026.4/api/python/algo_types.md#unwrapuvmethod)):

* `Isometric`: minimizes edge length distortions using [ARAP](http://cs.harvard.edu/~sjg/papers/arap.pdf) solver.
* `Conformal`: minimizes face angle distortions using [ABF++](https://www.cs.ubc.ca/~sheffa/ABF++/abf.htm) solver.

### Channel

UV channel to run the unwrapping on. If lines of interest are used, the channel corresponds to the destination where the new UV coordinates are stored.

### Create seams from LoI

If checked, UV islands are created by considering lines of interest as boundaries (in other words, as cutting lines over the mesh surface). Otherwise, islands defined by existing UV coordinates are used.

Lines of interests can be computed by [algo.segmentMesh](/asset-transformer-sdk/2026.4/api/python/algo_functions.md#segmentmesh), for instance.

### Iter max

Solver stopping criterion: maximum number of iterations allowed.

### Tolerance

Solver stopping criterion: error threshold.