1. EEC-693/793 Applied Computer Vision with Depth Cameras
Lecture 13
Wenbing Zhao 1

2. Outline Introduction to Unity3D Based on Book:
Beginning 3D Game Development with Unity 4

3. Creating a New Unity Project
Open Unity
Select the Create New Project tab, change location folder to KinectUnity
Select packages for import, then click Create 3

4. Unity 3D Layout 4

5. Scene View Where you plan and execute your ideas
To show the grid, toggle off the game overlay button 5

6. Hierarchy View Shows what’s in the currently active scene.
GameObjects that are dynamically added and removed from the scene during runtime will appear here when they are active in the scene
By default, the main camera is added 6

7. Project View
Contains all the assets available to the current project, as well as all scenes or levels available for the finished game or application 7

8. Inspector
Inspector is used to access various properties and components for objects you’ve selected in either the Hierarchy or Project views 8

9. Toolbar
Transform tools: provide functionality for navigating the scene and transforming objects
Left most button: pan, orbit, zoom tools for navigating and adjusting scene view
Pan tool: default, left click and drag to move the view around
Orbit tool: hold the Alt key while clicking left click and dragging
Zoom tool: Alt + right mouse click
Other three buttons: move, rotate, and scale 9

10. Toolbar Privot point and coordinate system tools:
Objects can be transformed in different coordinate systems and from different pivot points
Play mode controls
Layers control: Layers are used in Unity for controlling which objects are rendered by which cameras or lit by which lights
Layout control 10

11. Elements to Build a Scene
Assets: non-mesh special effects, physics materials, and scripts
GameObject: base container for objects, scripts, and other components in Unity
Contains its transforms (location and orientation) and a few other properties
Component: items associated with objects, such as meshes, rendering types, sound, scripts, and colliders, as well as those that create or extend functionality with predefined behaviors 11

12. Creating Simple Game Objects: Cube12

13. Creating Simple Game Objects
To zoom, use middle mouse roller or Alt-right mouse click
To set the camera to match the scene view
Select the main camera in the hierarchy view
From the GameObject menu, choose Align with View
You can’t select objects in this view and, unlike the Scene view, it has no default lighting. You’ll have to use the Main Camera to see objects in the Game window 13

14. Creating Simple Game Objects
Toggle the built-in lighting off and the scene lighting on, by clicking the light button
The cube is now lit only with the scene ambient light, as in the Game window
Try out zoom, orbit and pan 14

15. Selecting and Focusing
To focus the viewport back to the cube, or to “find” the cube, do the following
Make sure the cube is selected in the Hierarchy view.
Put the cursor over the Scene window.
Press the F key on your keyboard
You can view scene objects in several other modes
Wireframe, textured wire, textured (default) 15

16. Transforming Objects
In 3D space, the Cartesian coordinate system is used
X, Y, Z are color-coded with red, green, blue
Objects can be transformed (moved, rotated, scaled) around the scene
Select the cube, select the move button, click and drag on any of the three axis; Rotate is similar
Can also do these in inspector 16

17. Lights
Because there are no lights in the viewport yet, it went dark, just as in the Game window, when you toggle off the lighting button
Adding light
Focus the Scene view on the cube again and zoom out a bit
From the GameObject menu, choose Create Other ➤ Create a Directional Light.
Directional lights emit parallel rays, no matter where they are in the scene.
Move the light up and out of the way of the cube.
Rotate it in the Scene window until the cube is lit nicely in the Game window
Use alt-left mouse click, drag/orbit the viewport so you are facing the unlit side of the cube 17

18. Lights Changing light color: in inspector for light
Click and drag in the Color’s image/color swatch and watch the light’s color on the cube change
Choose something subtle.
Close the dialog 18

19. Material In the Inspector, select the Cube
2. In the Mesh Renderer section, click to open the Materials array list 19

20. Material
From the Assets menu, choose Create ➤ Folder, Rename the folder My Materials 20

21. Material
Right-click the new My Materials folder and, from the same Create submenu, choose Material 21

22. Material
A New Material entry appears in the Inspector, Name the new material TestBark
Drag and drop the material from the folder onto the cube in the Scene window.
In the Texture thumbnail window (not the Preview window), pick the Select button and, with the preview slider all the way to the left in the Asset Selector, choose Palm Bark Diffuse. 22

23. Material
In the Texture thumbnail window (not the Preview window), pick the Select button and, with the preview slider all the way to the left in the Asset Selector, choose Palm Bark Diffuse. 23

24. Scripting
A script is a program that controls the game objects in the scene dynamically, Unity support a number of programming languages
We will be using C#
To create a new script
Create a New Folder in the Project view using the right-click menu or Assets menu in the menu bar
Name the new folder My Scripts
With the new folder selected, right-click it to bring up the contents of the right-click menu. Select C# Script from the Create submenu 24

25. Scripting
To edit the script, click the open button. The MonoDevelop editor will open
using UnityEngine;
using System.Collections;
public class NewBehaviourScript : MonoBehaviour {
// Use this for initialization
void Start () { }
// Update is called once per frame
void Update () { 25

26. Scripting
The Start function is only called once as the scene is started and is a good place to initialize values that don’t exist until the game has been loaded
The Update function is checked at least every frame during runtime to see if anything needs to be executed
It can make a transform such as a rotation continuously loop, check to see if a particular condition is met, and many other things
To attach the script to the game object, drag the script file to the game object
Add the following line in the Update function, save the script, click play
If you want to animate the object on a per-second basis, use Time.deltaTime
transform.Rotate(0,5,0);
(0,5,0) refers to the X, Y, and Z rotations parameters that are needed by the Rotate function
transform.Rotate(0,5 * Time.deltaTime,0); 26

27. Scripting
We can also move the game object using the Translate function
You can also add private or public variables into script
Public variables are listed in the inspector and their values can be set their
Challenge Task:
Animate the cube such that it drops to the ground and then bounce back like a ball
transform.Translate(2 * Time.deltaTime,0,0); 27

28. Challenge Task
Add boundary check programmably for the game object when it reaches the boundary of the game view
Change direction of the movement for the game object each time it reaches the boundary, again programmably, so that the game object bounces back and force between the boundaries of the game view 28