Lattice Tool

Manipulates the layout of UVs as a group by letting you create a lattice around the UVs for deformation purposes.

To open the Lattice Tool, select it from the Transform > Tools section of the UV Toolkit or select Tools > Lattice from the UV Editor menus.

The following options appear in the Tool Settings window when you select Tools > Lattice > .

Lattice Settings

Columns

Specifies the number of columns for the current lattice manipulator. The minimum number of columns is 2 and maximum number is 8.

Rows

Specifies the number of rows for the current lattice manipulator. The minimum number of rows is 2 and the maximum number is 8.

Falloff

Specifies the lattice manipulator's level of influence or falloff value.

Use Bounding Rectangle

When on, the current lattice manipulator cannot extend past the outer edge or boundary of the target geometry.

Snap Settings

The lattice snap settings are relative to each UV affected by the lattice. Pixel Snap (Image > Pixel Snap) needs to be on in the UV Editor for the UV Lattice Tool Snap Settings to have any effect.
Placement
Select where control points snap to.
Snap Corner

When on, the UV lattice deformer’s control points snap to the corners of each UV.

Snap Center

When on, the UV lattice deformer’s control points snap to the centers of each UV.