The object tree

The white section in the upper left of Figure 1 is the object tree.

To create a world, you begin with a background scene (such as the desert shown in Figure 1).

Then you add objects to the scene (such as the coach shown in Figure 1).

As you add each object to the world, an item appears in the object tree that represents that object.

Later on, you can click on an item in the object tree to select that object for a variety of purposes.