EEC-693/793
Applied Computer Vision
with Depth Cameras
Lecture 13
Wenbing Zhao
[email protected]
Outline
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Introduction to Unity3D
Based on Book:
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Beginning 3D Game Development with Unity 4
Creating a New Unity Project
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Open Unity
Select the Create New Project tab, change location folder to
KinectUnity
Select packages for import, then click Create
Unity 3D
Layout
Scene View
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Where you plan and execute your ideas
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To show the grid, toggle off the game overlay button
Hierarchy View
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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
Project View
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Contains all the assets available to the current
project, as well as all scenes or levels available for
the finished game or application
Inspector
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Inspector is used to access
various properties and
components for objects
you’ve selected in either
the Hierarchy or Project
views
Toolbar
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Transform tools: provide functionality for navigating
the scene and transforming objects
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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
Toolbar
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Privot point and coordinate system tools:
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Objects can be transformed in different coordinate systems
and from different pivot points
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Play mode controls
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Layers control: Layers are used in Unity for controlling
which objects are rendered by which cameras or lit by
which lights
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Layout control
Elements to Build a Scene
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Assets: non-mesh special effects, physics materials,
and scripts
GameObject: base container for objects, scripts, and
other components in Unity
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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
Creating Simple Game Objects: Cube
Creating Simple Game Objects
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To zoom, use middle
mouse roller or Alt-right
mouse click
To set the camera to
match the scene view
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Select the main camera in
the hierarchy view
From the GameObject menu,
choose Align with View
Creating Simple Game Objects
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Toggle the built-in
lighting off and the scene
lighting on, by clicking
the light button
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The cube is now lit only
with the scene ambient
light, as in the Game
window
Try out zoom, orbit and
pan
Selecting and Focusing
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To focus the viewport back to the cube, or to “find”
the cube, do the following
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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
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Wireframe, textured wire, textured (default)
Transforming Objects
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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
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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
Lights
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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.
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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
Lights
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Changing light
color: in inspector
for light
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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
Material
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In the Inspector,
select the Cube
2. In the Mesh
Renderer section,
click to open the
Materials array list
Material
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From the Assets menu, choose Create ➤ Folder,
Rename the folder My Materials
Material
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Right-click the new My Materials folder and, from the
same Create submenu, choose Material
Material
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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.
Material
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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.
Scripting
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A script is a program that controls the game objects in the
scene dynamically, Unity support a number of programming
languages
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We will be using C#
To create a new script
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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
Scripting
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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 () {
}
}
Scripting
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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
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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
transform.Rotate(0,5,0);
(0,5,0) refers to the X, Y, and Z rotations parameters that are needed by the Rotate function
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If you want to animate the object on a per-second basis, use
Time.deltaTime
transform.Rotate(0,5 * Time.deltaTime,0);
Scripting
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We can also move the game object
using the Translate function
transform.Translate(2 * Time.deltaTime,0,0);
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You can also add private or public
variables into script
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Public variables are listed in the inspector
and their values can be set their
Challenge Task:
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Animate the cube such that it drops to the
ground and then bounce back like a ball
Challenge Task
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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