Smooth Mesh

The Smooth Mesh Preview feature controls how Maya displays a polygon mesh in the scene. The mesh can be displayed either un-smoothed, fully smoothed, or in both modes simultaneously.

You can enable this option under the Smooth Mesh section on the polyShape node for the mesh.

The Smooth Mesh Preview display modes are controlled by first selecting the mesh and then pressing the Hotkeys: 2 or 3. In addition, the level of smoothing/subdivision that occurs on the Smooth Mesh Preview can be controlled via the Hotkeys: Page Up, Page Down. Other attributes for this feature are set on the polyShape node via the Attribute Editor. Press the 1 key to turn off the Smooth Mesh Preview feature so that the mesh displays in its default display mode.

The following describes the Smooth Mesh Preview attributes available on the polyShape node.

Note Smooth Mesh Preview affects only the display of the polygon mesh in the scene view. If you render the mesh while Smooth Mesh Preview is turned on the mesh will appear in its original un-smoothed state in the final image.

If you want the mesh to appear smoothed in a rendering you can convert the smooth preview to a smoothed polygon mesh using Modify > Convert > Smooth Mesh Preview to Polygons or to a subdiv proxy using Proxy > Subdiv Proxy.

Smooth Mesh Preview: Turns the Smooth Mesh Preview feature on or off. The default setting is off. If the feature is on you can turn off Smooth Mesh Preview by selecting the polygonal object and then pressing the 1 key.

Display

Determines the display mode for Smooth Mesh Preview. Two display modes are possible:

Cage + Smooth Mesh: Press the 2 key to display the selected polygonal mesh in this mode. The original un-smoothed version of the mesh is displayed in wireframe (cage) as well as a smoothed shaded preview version of the mesh simultaneously. The Edit options lets you specify whether you can select and edit components on either of the separate versions of the mesh, or both, by setting it to Cage, Smooth Mesh, or Both.
Smooth Mesh: Press the 3 key to display the selected polygonal mesh in this mode. Only the smoothed preview version of the mesh is displayed in this mode. You select and edit components on the smoothed preview when working in this mode.

Note
When editing components on the mesh in either preview mode, the transform manipulator always appears in the location of the component as it appears on the original version of the mesh.

Subdivision Levels

Display Subdivisions: Controls whether the subdivided components in the smoothed preview are displayed on the smoothed preview version of the mesh. Subdivided components will be displayed when a check mark appears.
Preview Division Levels: Controls the number of times the original version of the mesh is subdivided (Default hotkeys: Page Up, Page Down). The slider range is between 0 and 4. The default setting is 2. A value of 0 indicates no smoothing while a value of 4 is the highest smoothing within the range of the slider. You can input values higher than 4 in the text field.

Note
Whenever a polygon mesh has an associated subdiv proxy object and the Smooth Mesh Preview option is turned on, the Page Up and Page Down hotkeys will only control the smooth level on the subdiv proxy.
Use Preview Level for Rendering / Render Division Levels: See Use Preview Level for Rendering / Render Division Levels of the Rendering guide for more information regarding these attributes.

Extra Controls

Continuity: Controls the amount of smoothness on the smooth mesh preview. The slider range is between 0 and 1. A value of 0 applies no smoothing.
Smooth UVs: Applies the same smoothing operation to the UV texture coordinates as occurs on the vertices. Smooth UVs is on by default and provides better results for UV texture coordinates.
Propagate Edge Hardness: Copies the edge hardness values from any hardened edges on the original mesh to the associated new edges on the Smooth Mesh preview. The default setting is off.

Map Borders

Controls how UV borders are smoothed when the Smooth UVs option is turned on.

Do not smooth: Border UVs are not smoothed.
Smooth Internal: Internal UVs are smoothed. This is the default setting.
Smooth All: All UV borders are smoothed.

Preserve

Specifies what components will remain unaffected by the Smooth Mesh Preview.

Geometry Borders: This option preserves the properties of border edges on the mesh.
Hard Edge: Preserves the properties of any existing manually hardened or softened edges.

Notes on Smooth Mesh Preview

When the Edit option for Cage + Smooth is set to Both you may want to change the active and inactive display colors for the Smooth Mesh Preview to more easily differentiate between the cage and the smoothed versions of the mesh. Select Window > Settings/Preferences > Color Settings and then choose either the Active or Inactive tabs to set the related active and inactive color settings found in the Smooth Mesh Preview section of Colors preferences window.
If you turn on Smooth Mesh Preview for one or more meshes that contain 15,000 polygons each or more you are prompted with the following message: "The selected mesh <object name> contains a large number of faces and may take a while to smooth or run out of memory. Do you want to continue with smooth mesh preview?". This message indicates that the interactive performance may be affected if you proceed with using the Smooth Mesh Preview on these high polygon count objects. There are a few ways you can modify the triggers for this warning.
If you want to set the default face limit to another value, for example: 20,000 polygons, you can type the following in the command line:

optionVar -intValue smpSizeOfMeshForWarning 20000;

Alternatively you can disable the warning altogether by typing the following in the command line:

optionVar -intValue smpSizeWarningDisabledForAllPolys 1;

To re-enable the message, input the same command with a value of 0.