You can control which types of objects are selected when you click in
the Design
View or use the mouse to select multiple objects in the Design View.
The Pick Filter combo box () allows you to set a filter for
what the LevelEditor selects when you click within the Design View:
With a pick filter active, if you click on an object that is not included within the filter, your click is passed to objects behind or within that object. For example, if you specify the “Basic Shapes” pick filter, and click on a linear that is in front of a cube, the cube is selected rather than the linear; the linear is not selectable. Using the filter allows you to select one or more basic shapes to work with them (for example, to rotate them) without affecting the linear (or any other object that is not a “basic shape”) that is near these objects.
These pick filters are provided as examples; a programmer can add additional pick filters that are specific to your game development project. For example, you might want to add a filter for “No Terrain Objects” so that you can easily click objects on a terrain without ever accidentally selecting the terrain itself.