Repositions the UV shells for selected objects so their arrangement is improved. The desired workflow is generally to lay out UV shells so they are not overlapping.
The default settings give the best results in most situations.
Prescale
Scales the area of the UV Shell proportional to either the surface area of the selected objects in object space or world space before laying out the UVs. Prescale is usually combined with Uniform Scale mode to scale UVs from multiple objects into a single UV region.
Prescale is only available when Layout Objects is set to Single or Multiple Objects (non-overlapping).
Automatically scales the UV shell to accommodate the selected objects’ surface areas in object space.
For example, the UV Shells for a scene consisting of 5 spheres of radius 1 will appear equal in size using the Object setting regardless of their individual scaling. Scaling only affects the objects’ size in world space.
Shell stacking
Determines how the UV shells get stacked in relation to each other when laid out in the UV Texture Editor.
Layout UVs creates a bounding box around each UV shell and then lays out the UVs so that the individual bounding boxes are positioned close together. Sometimes when the borders of two UV shells are positioned very close to each other, the two UV shells may end up sharing the same pixels on a texture map.
When this situation occurs, a portion of one texture may bleed onto another or may wrap incorrectly on the surface, resulting in visual artifacts. When painting a texture, overscanning can also cause the paint to spill onto the adjacent piece.
To avoid this situation, you’ll want to specify a spacing preset to ensure that there is at least one pixel separating the individual UV bounding boxes. Select a preset that corresponds to your texture map size. If you don’t know the size, select a smaller map, which will result in a larger spacing between adjacent shells in the UV space. (The smaller the map in pixels, the bigger the UV spacing must be between bounding boxes.)
Select Custom to set the size of the space as a percentage of the map size (in the Percentage space box) and enter a distance value that is appropriate for your texture map.
A set of common settings for Scale U, Scale V, Offset U and Offset V. The following table outlines the presets.
Label | Scale U | Scale V | Offset U | Offset V |
---|---|---|---|---|
Bottom Half | 1.0 | 0.5 | 0.0 | 0.0 |
Top Half | 1.0 | 0.5 | 0.0 | 0.5 |
Left Half | 0.5 | 1.0 | 0.0 | 0.0 |
Right Half | 0.5 | 1.0 | 0.5 | 0.0 |
Bottom Left | 0.5 | 0.5 | 0.0 | 0.0 |
Bottom Right | 0.5 | 0.5 | 0.5 | 0.0 |
Top Left | 0.5 | 0.5 | 0.0 | 0.5 |
Top Right | 0.5 | 0.5 | 0.5 | 0.5 |
Full Square | 1.0 | 1.0 | 0.0 | 0.0 |