The Projection modifier's Selection rollout is for managing sub-object selections.
Interface
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Cage
- Click to turn on the Cage sub-object level.
The Cage is the surface from which normals are projected. At the Cage sub-object level, you can adjust the cage manually by transforming sub-object selections of cage vertices.
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Face
- Click to turn on the Face sub-object level.
The Face sub-object level lets you assign different source geometry to different portions of a surface.
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Element
- Click to turn on the Element sub-object level.
The element sub-object level lets you assign different source geometry to individual elements. (An element is a group of contiguous faces.)
- Shrink
- Reduces the sub-object selection area by deselecting the outermost sub-objects. If the selection size can no longer be reduced, the remaining sub-objects are deselected.
- Grow
- Expands the selection area outward in all available directions.
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With Shrink and Grow, you can add or remove neighboring elements from the edges of your current selection. Shrink and Grow work at any sub-object level.
- Ignore Backfacing
- When on, selection of sub-objects affects only those facing you. When off, you can select any sub-objects under the mouse cursor, regardless of visibility or facing. If multiple sub-objects lie under the cursor, repeated clicking cycles through them. Likewise, with Ignore Backfacing off, region selection includes all sub-objects, regardless of the direction they face. Default=off.
- Get Stack Selections
- Click to collect sub-object selections from modifiers that are below the Projection modifier on the stack.
- Select SG
- To select by smoothing group value, use the spinner to set the number of the smoothing group, and then click Select SG.
- Select MatID
- To select by material ID, use the spinner to set the ID number, and then click Select MatID.
- Sub-material drop-down list When a multi/sub-object material is applied to the low-res object, this list shows the names and numbers of sub-materials that are assigned to faces or elements of the object. When you have selected by material ID, the corresponding sub-material appears in the field above the list.
- Clear Selection
- When on, each stack, smoothing group, or material ID selection you make replaces the previous selection. When off, each new selection is added to the previous selection set. Default=on.