Presentation on theme: "Building Game UI with WebKit Christopher Stott GDC Canada – May 6 th 2010."— Presentation transcript:
Building Game UI with WebKit Christopher Stott GDC Canada – May 6 th 2010
Building online frontend can be expensive. There’s a way that makes things a lot easier. Not without trade-offs.
skate’s always been a sharing game
Over 3 million videos uploaded Over 20 million videos watched Players shared over 400k spots
May 11th !
skate.feed Extensible system. We can add new messages even after we ship. Gives us the chance to highlight DLC Permeates through the entire game You, your friends and the wider community
Landing page. What’s been happening since you last played?
View the videos, photos and parks your friends created as you launch into the game.
‘Friend beat your challenge score’ ‘You’ve been invited to a team’ ‘Friend uploaded a skate.park’ ‘Friend uploaded a video to skate.reel’ ‘Content was featured’ ‘Team Logo was changed’ ‘Somebody joined your team’ ‘Your friend unlocked a new trophy / achievement’ ‘New DLC available for download’ What messages do we send?
Teams can compete together and create together. Plenty of tools for customising the experience and communicating.
skate.Park Create a park. Share with friends & community. Play online together in it.
INTRODUCTION TO WEBKIT
What is WebKit? At the heart of many modern web browsers : chrome / safari / iphone / other smart phones
Web Layout Engine Heart of a web browser Job to render HTML Responds to user input Reads resources from network
EA took WebKit & got it working on consoles
How did Skate 3 use it? Used it for about 50% of our UI Particularly online-connected features – Team Management / Team Profiles – skate.Feed landing page – Leaderboards – Player Profiles
It isn’t about letting users go to arbitrary websites within the game. Present them with a walled garden.
T Two key concepts of the talk Using a web layout engine to build UI Dynamically serving content from online Separate ideas, but fit naturally together.
Very new. First console game to integrate WebKit Has huge potential, but plenty to prove Not a silver bullet Not right for all feature sets Requires different skill sets from those working with it
WEB DEVELOPMENT IN 5 MINUTES
CONTENT THE HTML PART
HTML Content of the page, separated from how it looks & how it behaves. Let’s us focus on what information should be on screen, separately to how it’s presented.
What’s AJAX? Basically means ‘Background Update’ Initiated by client (user activity or timer) Way to update the page without doing an expensive & jarring full page load.
How content gets onto a page
Where does HTML come from? file://Real Web ServerIn-Game Web Server Really that’s entirely up to you One of the most important points of the talk Most powerful is a combination of all three.
Bring your own backend.
APPEARANCE THE CSS PART
CSS Also us to globally set up style. Separates the Artist’s work from the Engineer’s
CSS Zen Garden Quick highlight of the power & flexibility Exact same HTML, but radically different appearance An artist could reskin an entire game without talking to an engineer
Shared Components Let’s us quickly build new screens Leverage already developed components Drops cost of development eg. Tab Bars, Pagination, Dynamic Updating pages
Need people on the team with these skills to succeed
LOWER DEVELOPMENT COSTS
why? because we can act faster
Decouples things Decouples artists from engineers Decouples the data source from the presentation Decouples the logic from the game code
Fast Iteration Break the usual compile-link-run-test cycle Can see things in game earlier Test most changes inside a browser Fewer people can do more We estimate we were at least 4x more productive
Fix bugs faster Bugs are often just less complex / easier to fix Iteration time helps Can get changes into QA’s hands faster skate3’s Community Scrum had half the projected number of bugs & we could fix them far faster.
Different from building regular web page? No mouse / keyboard / cursor Needs to fit with the rest of the game TRCs to comply with on consoles
Should feel like game frontend & not a web page
Dealing with change When new information comes in, need to update. No ‘push’. Have to poll for updates (AJAX) Handle the cursor when page layout changes.
How to navigate page properly with only a controller?
Needs to deal with pages that change dynamically, where new arbitrary content is added or removed. Don’t want to hardcode, maintainance would be a nightmare. Can hardcode. As a fallback.
Very simple system for attaching controller buttons to actions. Left Trigger Controller Buttons
Banish cursor. No where else in the game uses it.
Highlight the ‘current’ element Using CSS & jQuery, came up with a simple system for to highlight the element the cursor is hovering over, without needing to render the cursor.
INTEGRATION WITH REST OF GAME.
WebKit Input Transport Handlers Texture Game Actions
Pick the appropriate art style
Don’t be scared to mix Flash & WebKit Room for a hybrid UI-model
Custom URL handlers Like http points to a web resource browser:// skatepark:// dlc:// skatereel://
Presenting WebKit WebKit renders to a texture. That’s all. Up to you how to present that texture – Fade in / Animate in – Overlay over the rest of the game with alpha – Transform and present in 3d On skate we’re always full screen and playing a Flash intro & ambient animation on top.
Animation Global: Animating the entire webkit texture Local : Animate within the page (CSS + JS) jQuery provides easy way to implement simple animations No where near as powerful as Flash tools
Debugging Much easier in Chrome Great developer tools an artist can use Harder in game, but possible. Mostly printf’s.
Memory can be a challenge Code’s in a DLL – about 6 megs Pages typically require 6-8 megs to display Tighter on memory you are, the more you have to worry about the page.
Overall Makes building online connected UI much easier Overall 4x productivity win & easier to final Needs people willing to learn the right skills There are lessons for everyone to learn. Some sacrifices necessary on visual quality Memory could be an issue
Potential Uses Prototyping Launch page Sign up / Sign in Flows In Game Media / UGC Galleries Video Libraries Tutorials Team Management Messaging
Skate played it safe Couldn’t dedicate significant resources to this For a long time this was just a ‘science project’ Went for a ‘safe’ implementation that we could guarantee we could ship. Meant we never had to cut anything. Plenty of lessons learned to take it to the next level for the next project
Benefits aren’t exclusive to WebKit, anyone can… Focus on being data-driven Build shared components Deliver content & layout from a server Find a way to get iteration times down
Current WebKit naturally aligns with a lot of trends happening in the industry right now. – Lower development costs – Pushing Direct-to-Consumer – Social & Always Connected Gaming
Thanks! GDC for inviting me Jeff Howell & Brian Lindley Joe VanZeipel & Hideki Bessho Arpit Baleva, Chris Sidhall, Paul Pedriana Skate3 Team & Blackbox for their support