1. Quick Intro to Unreal
Lecture 7

2. My (totally-biased) Thoughts
Unity
Very clean organization
More programmer-friendly (than Unreal)
A good model for (parts of) our engine.
Strong mobile support
Licensing
Personal = free, slightly limited
Subscription for others
No royalties
Unreal
Very dis-organized
Of course…I’m a n00b
More powerful*
Many FX turned on by default (FSAA, motion blur, etc.)
Unity has many of these – just not on by default
Probably more graphically advanced.
A resource-hog: overheats my PC’s
More for non-programmers
Blueprints
C++ scripting is totally for programmers
Limited mobile support
Licensing
totally free until you make $3K/quarter using it, then unreal gets 5% of profits.

3. interface Start it up! There are a number of starting projects
1st person, 3rd person, puzzle, racing, etc.
Let’s use 3rd person with starter content.
World Outliner (like Unity’s Hierarchy): a Scene Graph
Parent-child relationships
Content Browser (bottom-left): collection of assets
Details: (like Unity’s Inspector)
View / create components (do this in blueprints)
Edit component properties
Scene (middle)
Click the play button to enter “game mode”

4. View manipulation Virtually identical to Unity’s
‘F’: Frame selected object (or double-click name)
Right-click + WASD + QE
Scroll-wheel to zoom
Click the view box in the upper-left of the 3d scene to change from:
Perspective, Ortho-front, Ortho-side, etc.

5. Object manipulation [Add a 3d cube]
W, E, R toggle translate, rotate, scale
Or the buttons in the upper-right of the 3d scene
Local / Global button (earth icon next to ^)
Numeric values in the Details panel

6. blueprints Similar, but more pervasive than Prefabs in Unity
Different Types
To set up a template for a game object (and its components) – like a prefab
To set up a game mode
Default character
The tick rate
Default HUD
A blueprint for the level (a carryover from UE3, sort-of deprecated)

7. Different base-types
Used as a base when creating a new blueprint or C++ class
Actor: close to Unity’s GameObject
Very basic functionality
Pawn: an actor that can be “possessed” and receive controller input
Character: like a pawn, but adds a articulated mesh
PlayerController: an input-drived controller for a pawn
ActorComponent: a re-usable component that can be added to any actor.
… (there are MANY others)

8. Scripting overview Two types Two examples Visual Scripting (Blueprint)
Connect Nodes together
Like a flowchart
Cool “power” effect while running
Good for n00b programmers and artists
C++
It is C++, but it doesn’t look like it
Tons of pre-processor hacks to connect to the editor
Builds a dll that is loaded by the engine at run-time
Much faster than Visual Scripting at run-time
Most professionals seem to recommend this
Uses Visual Studio 2015
Two examples
Bouncing, rotating coin (Visual)
Character controller (C++)

9. Visual Scripting example
Import the coin fbx asset
Make a new actor blueprint
Add a static mesh component (the coin mesh asset)
Add a box collider
Add variables:
rotate-speed (float)
translateMin and Max (floats)
translatePeriodMultipler (float) …
(not really required – just an excuse)
Add a update_transform function
Takes dt (float) as input
Write the spaghetti code
Hook it up to the EventTick in the Event Graph

10. tags and layers Tags Unreal doesn’t have these
You can certainly just make a variable for it, though.

11. Input System Axes and Actions (similar to Unity)
Actions: True / False (‘a’ button on gamepad)
Axes: slider (-1 to 1 usually) (w/s or left-analog stick)
Edit => Project Settings => Input
Configurable (remappable)
Note the names
e.g. “MoveForward” / “Vertical” axes
e.g. “Jump”
Intentionally not a gamepad / key id or name.
[Discuss benefits for game designers]

12. C++ “scripting” Create a new public C++ class (based on Character)
Look at the non-standard macros added to the class.
Don’t mess with the “extra” stuff
Xyz.Generated.h
The macros in front of your class and methods
We’ll need to mimic these when expanding the class.
My example is from

13. C++ “scripting”, cont.
[Do it and build it]

14. Interacting with other G.OBJ’s
Option1: Make a public GameObject variable
plus: level-designer can set it
negative: fixed before run-time
Option2: Find it by name / tag
GameObject.Find or method
GameObject.FindGameObjectsByTag or FindGameObjectByTag
Can modify what you search for at run-time.

15. Mecanim overview A rigged / animated model has n clips
walk, run, idle, etc.
Mecanim does the following:
Blends between two animation clips
Models a state-diagram
You modify animation variables in code.
The state diagram will transition to a new animation.
Frees you from a lot of repetitive code.
First step:
Import a model with animation clips
(optional) Under import settings, set the clip to loop

16. mecanim overview, cont. Step2: Open Animator (not Animation) window
Step3: Drag clips onto stage
Step4: Create transitions between clips
Step5: Tweak transition criteria / variables
Step6: Set variables in script.
[There’s much more you can do with Mecanim]
Modify how the two clips are blended over time.
Mask off parts of the skeleton …

17. GUI Overview A 2d overlay (HUD’s, minimaps, etc.) Composed of:
A canvas: Unity automatically creates one
Buttons, Text-boxes, etc.
The layout is pretty self-explanatory
Unless you get into sprites…another topic!
The 2D button (near the top) is very handy.
These elements can (and often do) have scripts!
NOTE: import UnityEngine.UI or you won’t see UI objects in script!