Dublin Unity User Group Meetup Sept 2015

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DEV TIPS FOR STARTING NEW UNITY PROJECTS

DUBLIN UNITYUSER GROUP

MEETUP SEPTEMBER 2015

BY DOMINIQUE BOUTIN

CTO @ DIGIT GAME STUDIOS

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AGENDA– About Me

– About Digit

– High Level Game Dev Process

– Unity As A Platform

– App Code Organisation

– App Flows

– App Flow Customisation

DEV TIPS FOR STARTING NEW UNITY PROJECTS

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MEDominique Boutin

CTO @ Digit Game Studios

Professional industry experience:

5 years: F2P game dev

15 years: game technology

Was Director of Dev&Tech @ Bigpoint HQ

Started using Unity with v2.0 in 2007

Was Virtools expert before switching to Unity

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THE DIGIT TEAM

Founded in 2012

Ireland’s largest game developer, based in the center of Dublin.

World leading team of engineers, artists and game developers.

Combined experience of launching 100+ titles on Mobile, Browser, PC and Console.

Experts in MMO strategy games and high fidelity mobile game development.

Staff of ~ 35

Digit’s first title is on 5 platforms and everybody plays in the same big world !

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COMING SUMMER 2016

?

Digit’s second title is an iconic AAA-IP based mobile strategy MMO

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Indie?

Decide: project for learning or project for publishing?

Do active risk managent:

reduce the risk to fail using a good approach

Key:

Move risks to very early stages of any project

(where it’s cheaper to

handle)HOW WE MAKE GAMES

HIGH LEVEL GAME DEV PROCESS

8 HOW WE MAKE GAMES

HIGH LEVEL GAME DEV PROCESS

Preproduction Production Release Post Release

Exploration

Validation

Core definition

Stretch goals

Tech Vertical Slice

First Playable

Tools

Team Rampup

Full Production

Alpha

Content Completed

Beta / Soft Launch

Fine Tuning

Full Release

Hot fixes

New Content

New Gameplay

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You don’t do FarCry3 for the WiiWork and design for limitations of Unity and target platforms

Unity is closed source butVery extensible and customisableNot only for programmers: include designers, artists etc.

Unity promotes one way of doing butNot always the best

But also allows to be used differently

UNITY AS PLATFORM

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APP CODE ORGANISATION

RELATIONS INSIDE YOUR CODE

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– It’s about

• How do elements communicate with each otheror use each other

• Approach for references and dependencies

• Events vs direct usage / calls

• Avoiding processing overhead (GC, lookups etc)

– Also

• Code base easy to understand?

• Code base easy to extend or to refactor?

• Easy to debug?

• Testautomation possible?


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– Don’t follow industry recommendations blindly

• Programming cultures are too dogmatic (smells, best practices, patterns, testdriven etc.)

• Some solutions should not be ported 1:1 into Unity

• Avoid heavy frameworks (MVC frameworks, dependency injection frameworks etc)

– coding overhead and coding complication= High friction of change as it leads to = Low coder morale, especially for special cases

– You can achieve the same results much leanerAnd with better performance and maintability

• Avoid over abstraction by having an interface for everythingBe pragmatic!


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At Digit

• Composition over inheritance (Has-a vs Is-a)

• Related topics are organised as groups and sub-groups via namespaces and object composition

• Multi-Layered / -tiered APIs (think of Physics, Networking etc.)

– Don’t hide internals

– Instead layer APIs (internals, low level, service level)

• Use self-speaking names (that’s actually not easy)

• Comment smartly to avoid study of code context

• Rely on the programmer to do his job well:Education over enforcement.


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At Digit

• One “singleton” called “Hub”

– Doesn’t do anything

– Initialised and populated at startup of the app

– High Level Topic-Groups

» Allows access all systems

» Use interfaces where stubbing/mocking for testing is desired but don’t force it globally through the entire code base

– Only main thread usage


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At Digit

• Hub-Groups usually lead to systems related to the topic

– Easy to “dot” to what you are looking for e.g.

Hub.App.LifecycleManager

– Manually use interfaces for systems if you want stubbing/mocking for testing but not recommended to force it as requirement

• Consider keeping a local reference to a system if it makes sense

• Expose C# Events for callbacks / signals related to the topic


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At Digit

• If you need decoupling consider using static c# events

– Plus usaging Code Generation to speedup creation of new events


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APP FLOWS

WHAT HAPPENS WHEN

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GAME ENGINE CORE LOOP

Traditionally something like

*Nowadays more parallelised

How do you organise your logic within a frame?

Network Physics Inputs Game Logic Rendering

GAME SCRIPT LOGIC LOOP?

Main Logic

Managers

Cameras

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Study:

Execution Order of Events

http://docs.unity3d.com/Manual/ExecutionOrder.html

*system could have been designed better

SCRIPT EXECUTION

ORDER




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SCRIPT EXECUTION ORDER

Use

• LateUpdate e.g. for updating camera movements

• Start to initialise and cache calculations or lookups

• Etc.

Also use Script Execution Order Settings• http://docs.unity3d.com/Manual/class-ScriptExecution.html

• Run somelogic upfront or after everybody body else

• You can also use this to proxy events into your custom framework via c# delegates in combination with non-destructible Gos and layered scene management

http://docs.unity3d.com/Manual/class-ScriptExecution.html

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CUSTOM APP FLOWS, INJECTION

– Permanently root app/hub manager script(s) into the Unity app

• Use a base-scene for app management

– and scenes as layers via Application.LoadLevelAdditiveAsync

• Use DontDestroyOnLoad on the managing GameObjects

• Note to SDK developers:

– Creating the persisting game object should be a service.Assue the game is already doing it and just want to pass gameobject or events along

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– Some unity APIs work with coroutines

• Make a coroutine starter component available that sits on your main app / Hub game object

• And can be passed into your systems e.g. for doing Web-Requests

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– Do you own event pump or

– Forward Unity events into your custom c# framework (if wanted)

• Expose events e.g. via c# delegate to your framework

• Not recommended:Specialise MonoBehaviour through inheritancee.g. to call via reflection

– Usually hybrid approaches are used

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CUSTOM APP FLOWS

– We recommend NodeCanavas (commerical product)

– Visual tools do help. Go for a healthy mix of code and data driven tools

– We worked with the author to make it work on 5+ platforms

– Behaviour trees are not only good for AI. In general for App flows quite useful (e.g. tutorials)

– Also comes with a visual state machine toolset

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CUSTOM APP FLOWSConsider using reactive patterns

• Automatic notification when a value changed incl. the new value

– Score data changed: UI is updated automatically

• For a piece of logic: listen to what you are interested in

• A data field can have multiple subscribers

• If you go for c# delegates, use code gen

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APPENDIX

• Use sub-folders (don’t pollute root)• Use Standard Asset Folder to split into

compilation units to save compilation time

digitgaming.com

WE ARE HIRING !

https://www.digitgaming.com/careers/

Dublin Unity User Group Meetup Sept 2015

Technology

Transcript of Dublin Unity User Group Meetup Sept 2015