Subdiv Surfaces > Texture > Automatic Mapping

Projects UV texture coordinates onto the selected subdivision surface from multiple angles simultaneously.

Subdiv Surfaces > Texture > Automatic Mapping >

Planes: Select the number of planes you are projecting from. The more planes used, the less distortion occurs and the more UV shells created. You can choose a projection mapping based on shapes with 4, 5, 6, 8 or 12 planes.

Optimize

Select how you want the projection optimized.

Less Distortion: Projects all planes equally. While this method provides the best projection for any face, you may end up with more pieces. It is particularly useful if you have a symmetrical model and you want the pieces of the projection to be symmetrical.
Fewer pieces: Projects each plane until the projection encounters a projection angle that is not ideal. This can result in larger pieces, and fewer of them.

Shell Layout

Select where you want the UV pieces to lie in the texture space.

Scale mode

Select how you want the UV pieces scaled within the texture space.

None: Performs no scaling.
Uniform: Scales the pieces to fit the 0 to 1 texture space without changing the aspect ratio.
Stretch to Square: Stretches the pieces to fit the 0 to 1 texture space. The pieces may become distorted.

Shell stacking

Determines how the UV shells get stacked in relation to each other when laid out in the UV Texture Editor.

Bounding Box: Creates a rectangular bounding box around each UV shell, then stacks the shells based on the borders of the bounding boxes. The UV shells will have more space between them when this option is set.
Shape: Stacks the UV shells based on the boundaries of each individual shell. The UV shells can be more tightly arranged to fit into any available spaces when this option is set.

Spacing Presets: Maya puts a bounding box around each piece and lays out the pieces so that the bounding boxes are very close together. If the shells end up positioned exactly next to each other, two UVs on different shells can share the same pixel and when painting a texture with the 3D Paint Tool, overscanning can cause the paint to spill onto the adjacent shell.

To avoid this situation, ensure that there is at least a pixel between the bounding boxes by selecting a spacing preset from this menu. 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 UV space. (The smaller your 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).
Percentage Space: If you select Custom beside Spacing Presets, enter the size of the space between bounding boxes as a percentage of the map size.

NoteAfter performing an Automatic Mapping projection, you can modify the Planes, Optimize, Layout, and Scale settings for the projection in the Channel Box. However, do not modify these settings after painting a texture—the UVs may change drastically.