Circle Select allows items to be selected in a circular radius around the mouse cursor. While in this mode, dragging with the left mouse button will select any items that touch the circle, and dragging with the right mouse button (or the left mouse button while holding the control key) will deselect all items that touch the circle.

Hit detection is discrete rather than swept. Only items directly within the displayed radius during a screen update will be selected. As such, very fast cursor movements may be able to pass over selectable items without affecting them.

Using the scroll wheel or the square bracket (\[/\]) keys will adjust the radius of the selection circle. Holding the shift key allows the radius to be adjusted in smaller increments.

Pressing the Enter (or C) key will accept all changes made to the selection and exit Circle Select mode. Pressing the Escape key will exit Circle Select mode while canceling all changes made to the selection, reverting it to its previous state prior to when Circle Select mode was initiated.

The type of item to be selected depends on the current select mode:
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[*]In [link=select_mode_vertex]vertex select mode[/link], vertices will be selected if their center falls within the selection circle. If the mesh is not in [link=wireframe]wireframe[/link] mode, vertices occluded by geometry will not be affected.
[*]In [link=select_mode_edge]edge select mode[/link], edges will be selected if any part of the line formed by the edge falls within the selection circle. If the mesh is not in wireframe mode, edges occluded by geometry will not be affected.
[*]In [link=select_mode_face]face select mode[/link], faces will be selected if any part of their surface falls within the selection circle. If the mesh is not in wireframe mode, faces occluded by geometry will not be affected.
[*]In [link=select_mode_face_corner]face corner select mode[/link], behavior is identical to vertex select mode as described above. All face corners associated with each selected vertex will be selected.
[*][!todo]Currently, bone, bone endpoint, and light selection modes are unimplemented, and these items cannot be selected by this selection tool.
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