Introduction to Unity. What is Unity? Games Made with Unity /666 Computer Game Programming Fall 2013 Evan Shimizu

Transcription

1 Introduction to Unity /666 Computer Game Programming Fall 2013 Evan Shimizu What is Unity? Game Engine and Editor With nice extra features: physics engine, animation engine, custom shaders, etc. Cross-platform distribution: Win, Win 8 Store, Mac, Linux, Native Client, Browser Plugin, Android, ios, PS3, Wii, X360 Scripted with C# or Javascript Assets can be in standard file formats Thomas Was Alone Endless Space Temple Run 2 Sir, You Are Being Hunted Gone Home Games Made with Unity Also: Project Eternity, Torment: Tides of Numenera, Shadowrun Online, Surgeon Simulator 2013, Shroud of the Avatar, Kerbal Space Program, English Country Tune, Deus Ex: The Fall, Race the Sun, Rochard

2 What Unity Does Unified Environment for Development Distribution on practically all platforms Integrated Editor and Asset Manager Scripting Interface What Unity Does Not Design your game for you Program your (entire) game for you Make art for you Make version control very easy (pre-4.2 apparently) The Unity Interface

3 Interface Project Browser Interface Hierarchy Interface Scene View

4 Interface Game View Interface Inspector Using Assets Asset refers to any external content 3D Models Max, Maya, Blender, Cinema4D, Modo, Lightwave & Cheetah3D format support through conversion Need to have software installed to use conversion Supports.FBX,.dae (Collada),.3DS,.dxf,.obj natively

5 Using Assets Textures (2D Art) Supports the usual formats,.jpg,.png, etc. Textures get assigned to materials, which then get assigned to models Imported textures on models will be converted to texture and material files in Unity Using Assets Material Contains the shader for a model You can write your own shader if you want Audio WAV, MP3, OGG, AIFF supported Automatically optimizes files for the platform the game is built for Unity Projects Each Unity Project is a Folder Assets are kept in the Assets folder Library is Unity s internal cache folder Output is where your builds go ProjectSettings is what it says but manual editing is not recommended

6 Unity Projects Unity.scene files are where the magic happens Contains information about how your assets are arranged Multiple scenes are allowed in each project How Unity Makes Things Go GameObject Node in Unity s scene graph hierarchy Each GameObject can have multiple Components attached to it GameObjects can have child GameObjects If you want something to do a thing, there must be a GameObject for it How Unity Makes Things Go Components Get attached to GameObjects and give them additional functionality Every GameObject has a Transform Component

7 How Unity Makes Things Go Component Types Camera Mesh Collider Physics Objects Particle System Audio Scripts! How Unity Makes Things Go Scripts C# is highly recommended, though Unity supports Javascript too C# support is through a modified version of the MonoFramework Unity s version is closest to.net 3.5 How Unity Makes Things Go Scripts Attached to GameObjects C# is highly recommended, though Unity supports Javascript too C# support is through a modified version of the MonoFramework Unity s version is closest to.net 3.5

8 An Aside About C# Language Features Object-oriented Single-inheritance Managed Memory Most object types are passed by reference An Aside About C# Types Value: int, float, bool, enum, struct Reference: Everything else (objects, strings, delegates, etc.) Literals have suffixes to indicate type 0.0 is a double 0.0f is a float An Aside About C# Properties Special shorthand for getters and setters for class values Can be small functions public float chanceheads { get {return 1.0f this.chancetails;} set {this.chancetails = 1.0f value;} }

9 An Aside About C#.Equals and == Be careful when using these C# is generally smart enough to use == correctly, as in comparing contents rather than if reference is the same Check == and.equals if getting unexpected results An Aside About C# Collections Unity s C# comes with the Collections library Collections are generic Declared as List<MyObject>, like C++ templates An Aside About C# Collections Types List<T> Dictionary<T> Queue<T> Stack<T> SortedList<T>

10 An Aside About C# Collections Can be iterated over with a foreach loop if contents are not modified foreach( KeyValuePair<string, string> kvp in mydictionary ) { Console.WriteLine("Key = {0}, Value = {1}", kvp.key, kvp.value); } An Aside About C# Functional Features Functions can be arguments in C# C# calls these Delegates I have not had to use these in Unity yet, so see online examples or ask me at office hours for more details Back to Scripting Script must have an object that is the same name as the file This object needs to inherit from MonoBehaviour Script should use UnityEngine and System.Collections Unity will do this for you if you create the script with Unity Assets > Create > C# Script

11 Scripting Unity provides functions for you to override to make things go Start Called on startup For initialization Scripting Update The really important one Called on every frame Do movement, input checking, etc. here But what about potential dropped frames? Scripting FixedUpdate Called with the physics engine update loop Runs on discrete timesteps Best place for physics-related code

12 Scripting LateUpdate Called after Update and FixedUpdate For things that need the results of the update to happen first OnGUI GUI Drawing function On a separate loop than the other updates Scripting Variables Declaring your variables in your class as public will allow Unity to display and manipulate them in the inspector GameObjects can be public and can be assigned defaults in Unity Variables can be modified while the game is running in-editor Scripting Getting Around the Hierarchy Getting attached components: Rigidbody rb = GetComponent<Rigidbody>(); Getting Other Objects Child Objects: foreach (Transform t in transform) Find By Name: GameObject.Find( name ) Find By Tag: GameObject.FindWithTag( tag ) Find Collection by Tag: GameObject.FindGameObjectsWithTag( tag )

13 Scripting Events Some components give you extra events to override See the Unity documentation for more info Scripting Transforms Position - Position in world space Forward - Blue axis (Z) in world space Up - Green axis (Y) in world space Right - Red axis (X) in world space Scripting Rotations Quaternions Can manipulate quaternions directly or through Euler angles Use Transform.Rotate(Vector3) or Transform.Rotate(x, y, z) to do basic rotations

14 Debugging Debug.Log( string ) is always good You can do step-through debugging too Launch MonoDevelop to edit your script Set breakpoints in MonoDevelop Start the Unity project Attach MonoDevelop to Unity. Run > Attach to Process and find your Unity process Version Control Unity 4.2 has apparently allowed for text serialization for free users Practically this means Git and SVN should work with Unity If you want to use source control, set it up immediately after creating a new project Version Control Setting up Version Control Edit > Project Settings In the Inspector Version Control > Meta Files Asset Serialization > Force Text Ignore Library and Temp folders and *.csproj, *.pidb, *.unityproj, *.sln, *.userprefs

15 Additional Resources Unity Documentation Manual Component Reference Script Reference Unity Tutorials Stealth Additional Resources Me Office Hours or if you can t remember that, dragon@cmu.edu works too