Launching the Unwrella user interface


To launch the Unwrella plug-in, select Create UVs->Unwrella from the Polygons menu to open the Unwrella user interface.

In Maya 2016 the menu Create UV’s has been renamed to just UV.

The Unwrella user interface


UV Set - Destination UV set. This is where the generated UV’s will be stored. If you leave the field ‘new’ empty, the existing set that is selected in the dropdown will be used. If you enter a name into the field new a UV set with that name will be created and used to store the unwrap result.

Unwrap - Unwrap the UV map. This creates a new modifier node for the selected mesh, calculates the new UV data and writes it into the selected (or new generated) UV Set. Using this button multiple times will add multiple Unwrella nodes to a mesh, not edit the parameters of already erxisting nodes. If you want to change your settings after applying Unwrella use Maya’s attribute editor instead.

Unwrap Mode - Picks the unwrapping method.

  • Organic unwrapping - this mode is suited for irregular shapes.

  • Hard surface - this mode is more suited for many architectural objects where organic unwrapping produces too fragmented results.

  • Pack existing - Uses the already existing UV charts and packs them together into maps without unwrapping anything.

  • Projection unwrap - Unwraps the geometry based on a given view perspective. Visible surfaces are distributed over the UV area while geometry not visible for the given view gets excluded. This allows a much more efficient use of UV space is the geometry is only seen from a fixed or slightly changing perspective. See Projection Unwrap for settings relating to this unwrap mode.

Texture stretch - The amount of stretching allowed. 0 means no stretching is allowed, 1 means any amount of stretching can be used.

Gutter padding - Distance between charts in the texture.

Texture Width - Texture width.

Texture Height - Texture height.

Lock Aspect Ratio - While this is enabled Unwrella will produce an unwrap for a square texture map. The Height option is consequently ignored and the width determines both dimensions. Disabling this option allows for unwraps suitable for non-square texture maps.

Keep Borders - If checked all UV borders that already exist on the mesh in the currently active UV set will be kept while unwrapping. This results in unwrapping results that are more conformant with certain workflows (i.e. manual texture painting). Please see the chapter about manually placed borders for further information.

Cut Grooves - Adds seams to edges that form a groove. The angle defines the threshold for seam placement. If the angle between the normals is higher than the given angle, a seam will be added.

Cut Ridges - Adds seams to edges that form a ridge. The angle defines the threshold for seam placement. If the angle between the normals is higher than the given angle, a seam will be added.

Pack Mode - Selects the used packing mode.

  • Classic - This is the packing engine used by old versions of Unwrella. It is preserved for compatibility reasons but in most cases the other types will produce better results. Keep in mind that this mode contains some limitations:

    • The classic mode uses the reference texture dimensions to determine its packing quality. Using high a high texture size has a significant performance impact.

    • Rotation cannot be adjusted and charts will always be rotated the same regardless of the rotation options chosen below.

    • This mode does not fill holes in UV charts.

    • Packing without any padding is not supported. This option will always result in some padding, even if padding is set to 0.

    • In most cases this mode is significantly slower than the other modes.

  • Efficient - This is the default packing and provides an optimized tradeoff between result quality and performance.

  • High Quality - This is similar to the Efficient type but it performs additional calculations to improve the packing results. It will be noticeably slower but will usually squeeze out a few more percent of texture area utilization.

Rescale - When this option is checked the individual UV charts are rescaled depending on the amount of mesh surface they cover. This results in pixels being more evenly distributred over the mesh. When it is disabled all charts will keep the exact size they had before the packing.

Pre-Rotate - This option rotates all charts to individual, optimal starting orientations. This is independent from the additional rotation orientations provided by the options below and will perform that individual rotation even if rotations are turned off there.

Rotation - These options provide additional rotations by the given angles to better fit the charts into the map. This happens independently of the starting rotation provided by the prerotate option above. Smaller rotation angles can provide more efficient chart arrangements in the map but calculations take more time.

Full Rotation - By default rotations will omit exact 180° alternatives to each rotation angle. This is done because an upside-down alternative of a chart provides very little improvement in quality while significantly increasing calculation time. Enabling this option will perform full circle rotations. This can slightly improve result quality but has a notable performance impact.

Tile UV - When this option is at the default of 1 x 1 all UV charts are packed into a single UV square with coordinates between 0.0 and 1.0. Increasing the number of rows or columns will distribute the charts among additional UV tiles to be used by additional texture maps.

Pick Camera - Chooses the camera which determines the perspective for the unwrap.

Angle - The angle towards the view direction that is used to consider surfaces for the unwrap. An angle of 180 degrees will consider all surfaces visible from the given point. Smaller angles will cause increasing amounts of geometry behind and to the sides of the view direction to be discarded.

Extend - Increasing this value allows for a greater angle of tolerance towards backfacing polygons. This allows inclusion of surfaces that are not visible for the current view but might become visible when the camera and/or object are moved or rotated.

This option can also be set to negative values. In that case surfaces will be discarded even though they are visible when their angle towards the camera becomes too high.

Orthographic - Ignores perspective and uses an orthographic projection to determine visible surfaces. The View Angle option is ignored in this case.

The attribute editor interface


Since Unwrella’s calculation is quite time consuming the node does not automatically propagate changes made in this interface or other nodes that are executed before Unwrella’s node to the output. In order to update Unwrella’s output you have to use the Apply button in the attribute editor. See the chapter ‘Updating Unwrella’s output’ for more information. Settings in this interface correspond to the functionality of the Unwrella user interface.