Session I: Setting Up and Using Unity 3D for VR¶

The User Interface¶

The interface in Unity is organized as a series of "windows" laid out in an adjustable grid. Windows can be resized and dragged around to a position that makes sense for your workflow. Each has at least one tab which identifies the and in the upper right hand corner a dropdown menu will let you close, maximize or add a new tab.

Unity Documentation: Learning the Interface

• Hierarchy: shows objects in the current scene and how they are nested as parents and children (sometimes this is for organization, sometimes this is for efficient operations or a group of objects)
• Scene: shows a view of how objects are arranged in a scene with an xyz axis indicator in the upper right corner
• Game: shows a view from the perspective of the camera - when you click the play button in the Toolbar, it will be brought to the front automatically and run your scene inside the editor
• Inspector: a view into the metadata of each object.
• Project: your file system directories under ./Assets which can be dragged into the Hierarchy, Scene, or certain places in the
• Console: this is the stdout of Unity - when you break stuff, errors show up here - and you can write there directly from scripts using Debug.Log("hello console");
• And more...: there are several additional window types that will help you perform more complicated functions (and, you can even create your own!) but these cover most of what you need to get started

Creating GameObjects¶

Now that you've got some sense of the interface, lets make some GameObjects!

In the main file menu, select GameObject > 3D Object > Cube. You should see a cube appear in the Scene window. If you do not see it, find the Cube in the Hierachy window and double click on it. That should bring the Cube into focus in the Scene view.

Notice that in the Inspector window, under the object name are a set of rows for Transform, MeshFilter, BoxCollider, MeshRenderer, and DefaultMaterial. These are all Components. Each has different properties available in the editor but they all have a link to documentation and a menu in their upper right corner.

Add some additional 3D objects to the scene such as a Sphere and a Cylinder.

Now, try creating an Empty. Notice that it appears in the Hierarchy tab as a GameObject and that it appears in the Inspector as a Transform.

Move, Rotate, and Scale¶

Just as the fundamental unit of a GameObject is a Transform, the fundamental actions you'll take on GameObjects in the Scene window are manipulations of that Transform.

The most obvious way to switch between these methods of manipulation is the Toolbar. When you click on one of the icons in the upper left, it changes how your mouse behaves in the Scene window (and )

But you don't really want to be sliding your mouse up to the Toolbar every time you want to move and rotate an object, do you? Of course not. The faster way to switch modes is to utilize the provided hotkeys. They are arranged optimized for right-handed users of QWERTY keyboards, but even if that's not you, they can still be really useful, so it's worth building the muscle memory to use them.

hotkey table

The complete list of hotkeys can be found at Unity Documentation: Hotkeys

Take a few minutes to play with the position, rotation, and scale of your objects (you may want to )

Notice that the colored lines correspond to the axis key in the upper right hand corner: red => x, green => y, blue => z. The direction they are pointing is the positive number.

If you maximized a Scene tab, select from the upper right corner again to unmaximize.

Working With Hierarchies¶

Once you have a few objects in scene, you can see them stacking up in the Hierarchy view, but right now the objects are probably all children of the scene itself. You can place objects in a hierarchy by dragging and dropping them in that window.

Let's go back to our basic objects and arrange them with a little more intention.

• add a Cylinder and rename it 'Axel' (you can do this in the Inspector window)
• add a Cube above it and rename it 'Gear'
• add a few spheres and position them at varying distances from the cube.
• make the cube a child of the cylinder.
• make the spheres all children of the cube.

Now you should have a set of five objects arranged in a hierarchy where:

[Scene]
|-- Axel
  |--Gear
    |-- Sphere
    |-- Sphere
    |-- Sphere

• select the 'Gear' in the hierarchy and change its scale.
• then, select a few of the spheres and change their scale.
• then, select the 'Axel' in the hierarchy and change its rotation

Working With Imported Assets¶

OK, enough with these cubes, spheres and cylinders - what else can we put in our scene? As you're getting started, it's much easier to prototype with creative commons or other free-as-in-beer licensed assets than to learn how to create them from scratch. You can find some suggestions for places to find assets of varying quality in the resources section.

When you import assets from other sources, however, they may not be optimized for Unity (much like free stock photography vs paid stock photography, good optimization is one of those things you should look for and expect as your project gets to a place you are willing to spend more money for assets). Here's a couple of things you may have to manage as you import things from different sources:

Avoiding Project Gotchas¶