Selection Preferences

General Options

Select Single Object in Region	When selecting objects using either the Rectangle or Lasso selection tool, only a single object is selected.
SI\|3D Selection Model	Switches on the same selection model as SOFTIMAGE\|3D for objects and components. If this option is off, use the following mouse and keyboard combinations: Use the left mouse button to node-select objects. Use the middle mouse button to branch-select objects and their descendants. Use the right mouse button to tree-select objects, or branch-select the chain roots of chain elements. However, there are couple of Selection preferences that can affect this behavior. Use the Shift key in combination with the left, middle, or right mouse buttons to add objects, branches, or trees to the selection. Use the Ctrl key in combination with the left, middle, or right mouse buttons to toggle the selection of objects, branches, or trees. Use the Ctrl+Shift keys in combination with the left, middle, or right mouse buttons to deselect objects, branches, or trees. If this option is on, use the following mouse and keyboard combinations: Use the left mouse button to toggle the selection of objects. Use the middle mouse button to toggle the selection of branches. Use the right mouse button to toggle the selection of trees, or toggle the branch-selection of chain roots of chain elements. However, there are couple of Selection preferences that can affect this behavior. Use the Shift key in combination with the left, middle, or right mouse buttons to add objects, branches, or trees to the selection. Use the Ctrl key in combination with the left, middle, or right mouse buttons to toggle the selection of objects, branches, or trees in the case of multiple selection. Use the Ctrl+Shift keys in combination with the left, middle, or right mouse buttons to deselect objects, branches, or trees.
Extended Component Selection	Switches on the SI\|3D selection model for components only. This allows you to perform multiple component selections without holding the Shift key. If both this option and SI\|3D Selection Model are off, use the following mouse and keyboard combinations to select components: To select new components and deselect any that are currently selected, don't press any modifier keys. To add components to the selection, press the Shift key. To toggle-select, press the Ctrl key. To deselect, press Ctrl+Shift. To deselect all, click or click+drag over an empty area of a viewport. With any of the above key combinations, use the left mouse button for components or the middle mouse button for clusters. You can also use the Cluster filter on the Select panel or press =. To display a context menu showing commands that are applicable to the selection, right-click anywhere on the object with selected components. If either this option or SI\|3D Selection Model are on, use the following mouse and keyboard combinations to select components: To add components to the selection, use the left mouse button. To deselect components, use the middle mouse button. To toggle-select components, use the right mouse button. To select clusters, use the Cluster filter on the Select panel or press =. To display a context menu showing commands that are applicable to the selection, Alt+right-click anywhere on the object with selected components in Windows (Ctrl+Alt+right-click on Linux).
Click to deselect	Deselects objects or components when simply clicking in the background of a viewport, instead of requiring you to click and drag in the background to deselect. This affects the Rectangle and Lasso tools.
Upon Selection using RMB on Chains	Determines the behavior when right-clicking to select chain elements: Chain Select branch-selects the chain root, even if the chain is part of a larger hierarchy. This is useful for quickly selecting a chain from any of its parts. Tree Select branch-selects the top-most object in the hierarchy. However, it doesn't select a model node if there is one. This makes it easier to animate and set keys on only those parameters that are within the model's namespace (the model itself is in the scene root's namespace). Model Select branch-selects the top-most object in the hierarchy, whether or not it is a model node. The Scene_Root object is not selected.
Upon Selection using RMB on Objects	Determines the behavior when right-clicking to select objects: Tree Select branch-selects the top-most object in the hierarchy. However, it doesn't select a model node if there is one. This makes it easier to animate and set keys on only those parameters that are within the model's namespace (the model itself is in the scene root's namespace). Model Select branch-selects the top-most object in the hierarchy, whether or not it is a model node. The Scene_Root object is not selected.

Rectangle Select Options

Surround Edges

When on, you must completely enclose edges to select them with the Rectangle and Lasso tools. When off, you need only enclose part of them. This item is also available directly on the Select menu.

Surround Polygons

When on, you must completely enclose polygons to select them with the Rectangle and Lasso tools. When off, you need only enclose part of them. This item is also available directly on the Select menu.

Raycast in Shaded Mode

Prevents the Rectangle selection tool from selecting elements that are occluded behind other elements in Hidden Line Removal, Constant, Shaded, Textured, and Textured Decal viewing modes.

This option is ignored if Override Object Properties is off in the Display Mode menu of a viewport.

Raycast Select Options

Include Backfacing Polygons

Allows you to select backfacing polygons with the Raycast selection tool by clicking on a silhouette edge shared by the backfacing polygon. When this option is off, the Raycast tool selects only polygons with normals facing the camera. This item is also available directly on the Select menu.

Selection Change Command

Executes the command specified in the adjoining box, each time a selection is made.