COMS W4172 : 3D User Interfaces

Prof. Steven Feiner

Date out: March 12, 2019

Date due: April 2, 2019

Assignment 3: Making a Machine

At this point, you've started to learn about some of the many ways to select and manipulate

objects in 3D user interfaces. Now, it’s time to try this yourself, using Unity and Vuforia to write

your first augmented reality app. You will construct an augmented reality app in which a user

can create, delete, select, and transform instances of virtual objects to assemble a simple

apparatus inspired by a Rube Goldberg machine . The goal is to prepare you to understand the

techniques and programming tools you’ll be using in your final project.

First, make sure that you included Vuforia in the version of Unity on your computer, which must

be no older than 2018.3.2. Whichever version of Vuforia is installed should automatically update

to the latest version ( Vuforia Engine 8 ). At the same time, we strongly suggest that you upgrade

to the current version of Unity (Unity 2018.3.8). If you did not check the Vuforia package box

when you installed Unity, you will need to reinstall Unity and click that box in the installer. (Refer

back to Step 2 in our IA document on Installing Unity and Vuforia if you need help.) The Vuforia

Developer Portal will be a crucial resource throughout this assignment. Begin by reading the

Vuforia Getting Started page. You should also watch the following three video tutorials before

proceeding with the assignment: ARCamera prefab in Unity , Image Targets in Unity , and

Vuforia Play Mode for Unity . You will be using Image Targets in this assignment; therefore, it will

be essential for you to read the Image Targets guide to understand how they work. Your targets

should be defined in a Device Database (which we provide, as described below). You should

also read our IA document on Developing with Unity and Vuforia . ( Please be sure to familiarize

yourself with all documentation mentioned in this paragraph! )

All selection, translation, scaling, and rotation in this assignment should be accomplished based

on the relative positions and orientations of tracked Vuforia Image Targets, tracked parts of the

environment (on a device that supports Vuforia Ground Plane —if your device does not, please

contact us asap and we will lend you an Android phone that does), and your Android/iOS

device. These can be optionally accompanied by triggers or modifiers specified using one or

more button or touchscreen interactions. That is, you should not use the touchscreen for

selection, translation, scaling, or rotation, except as a trigger (e.g., tapping the screen), or a

modifier (e.g., touching the screen to modify some behavior). Note the additional requirement of

needing to use at least one toolbar for selection, as described below. Furthermore, triggers or

2D UI components should not be used to specify the magnitude of a transformation ; for