The Art and Zen of Mobile Game Creation with Flash

I gave this presentation to an audience of hundreds at the FlashForward event in Boston back in 2007.

CONFERENCE: http://www.flashforwardconference.com/

Transcript

1. The Art and Zen of Mobile Game Creation with Flash Scott Janousek flashforward@scottjanousek.com
2. Presentation Resources You can find everything here: http://www.scottjanousek.com/flashforward (will be available Post‐Conference …)
3. Me GENERAL INFO – From Boston, Massachusetts, USA – Working with desktop Flash for six years – Developer , “Try” to be a Designer – Blogging about Flash (Mobile) for 4 years MOBILE – Working with Flash Lite 1.1, 2.0, 2.1 – Flash Lite 1.1/2.x Training Instructor – Coauthor: “Foundation Flash Applications for Mobile Devices” – Mobile Gaming Enthusiast – ™
4. Flash Lite Design, Development, Training, Consulting
5. Mobile Games Portfolio • Flash Lite 1.1, 2.x, (2.x games coming to 3.0) • Distribution: – Working directly with 3rd party mobile (game) companies – Flash Lite Exchange, Moket MCN (“in talks with”), Partnerships: Handango, ClickApps, other aggregators, etc. • Products soon – Don’t Wake the Dragon, MORE! Symbian Series 60 Content iRiver Clix game viliv p1 Sudoku game
6. Mobile Games “Worldwide revenue for mobile gaming subscriptions could increase from $3 billion to $10.5 billion in 2009.” – Juniper Research Ltd.
7. Mobile Game Markets “Power” – Power Gamers – High Learning Curve – More Expensive – Guilt in not finishing – More time investment “Casual” – Fun, Addictive – No learning curve – Inexpensive – No guilt – Less time investment
8. (Mobile) Game Genres • Arcade/Action – Snake, Bomber, Alien Invasion … • Role playing games (RPG) – Final Fantasy, etc. • Sports – EA SPORTS™ Madden 07 • Skill, Strategy, Logic – Mine Sweeper, Sudoku • Multiplayer – Mario Kart, Texas Hold’em • 2‐D, 3‐D Racers – Tron, Mario Kart • Card and board games – Slots, Blackjack, Monopoly • First Person Shooters – Quake, Doom … Above: these just happen to be Flash Lite games that fit some of the genres …
9. Mobile Game Design with Flash “Casual Games make most use of the inherent advantages of the mobile platform. People want to fill ‘dead time’ with easy to use, but fun games.” – Bruce Gibson, Research Director with Juniper Research.
10. Mobile Game Challenges • Smaller Screen Sizes • Color Depths • Limited Memory • Limited Processor • File Size • Battery Life • User Input • Walled Gardens • Portability • Learning Platforms • Fragmentation • … many more!
11. “Holy Grail” = W.O.R.A. • Write Once Run Anywhere • Nice idea for mobile, but … – Lots of devices, different capabilities, implementations, etc • Fragmentation is “fact of life” – Native, J2ME, etc – Flash Lite is NOT immune, but much LESS affected Handsets PDAs “Consumer Electronics”
12. Platform Decisions for Mobile Games
13. Flash Lite Players * * From Boston? Say “Play‐ahs”
14. Flash Lite Game Life Cycle DESIGN GAME TEST GAME DEVELOP GAME DEPLOY DISTRIBUTION DEPLOY OTHER PLATFORMS Idea/Concept Operators, Aggregators & Content Providers .sis packaging Other platforms … Symbian Series 60
15. Mobile Game Development with Flash “The Flash Lite Platform offers one of the best environments for rapid mobile game development for casual type content found today.” ‐ Me
16. Flash Lite 1.1 versus 2.x FL 2.x ‐ Class Based • Penetration = Lower • ActionScript 2.0 – Code Reuse – Modularity – Maintenance – Extensibility – Less time to learn – Larger project content FL 1.1 ‐ Timeline Driven • Penetration = Higher • “ActionScript 0.5” – Code Reuse – Modularity – Maintainance – Extensibility – Less time to learn – Smaller project content
17. Flash Lite 1.1 Syntax Refresher • tellTarget() – tellTarget( /player_mc/ ) { /:x =+ 1; } – movie clips can act as libraries (“function clips”) • eval() – Simulate Pseudo Arrays using variables and eval – x1 = “foobar”; i = 1; eval( “x” add i ); • Game State Frame Labels(menu, gameplay, etc) • More ... – My Flash Lite 1.1 “Reference Sheet” (PDF)
18. Flash Lite fscommand2 API • SetQuality • StartVibrate • StopVibrate • GetVolumeLevel • GetMaxVolumeLevel • GetSignalLevel • GetMaxSignalLevel • GetNetworkConnectStatus • GetNetworkRequestStatus • GetNetworkStatus • GetNetworkName • SetInputTextType • Quit • ExtendBacklightDuration (FL 2.x) • setFocusRectColor (FL 2.x) • UnEscape • GetPowerSource • GetBatteryLevel • GetMaxBatteryLevel • SetSoftKeys • ResetSoftKeys • GetDateDay • GetDateWeekDay • GetDateMonth • GetDateYear • GetLocaleShortDate • GetLocaleLongDate • GetLocaleTime • FullScreen • GetTimeHours • GetTimeMinutes • GetTimeSeconds • GetTimeZoneOffset • GetTotalPlayerMemory • GetFreePlayerMemory • GetLanguage • GetDeviceID • GetPlatform • GetDevice • Launch • Escape retVal = fscommand2( “FullScreen”, true ); //‐‐ fullscreen mode (if supported) fscommand2’s execute immediately and have return values
19. Device Keys/Text Input • Target devices often vary • Keys: 0,1,2,3,4,5,6,7,8, #, * • Soft Keys – Typically LEFT, RIGHT – FL 2.x supports multiple softkeys • Text Input – FL 1.1 uses device for input – FL 2.x built in text input (T9) • 5 Way Direction Joystick – UP, DOWN, LEFT, RIGHT, SELECT
20. Keys in Flash Lite 1.1 • Flash 4 style syntax • “Key Catchers” – button off Stage with ActionScript on( keyPress “<UP>” ) { /player_mc/:y += 1; } • Soft Keys – Typically 2 or more retVal = fscommand2( “setSoftKeys”, “left”, “right” ); on( keyPress “<PAGEUP>” ) { //‐‐do xyz } EXAMPLE
21. Keys in Flash Lite 2.x //‐‐ method #2 – Key Listener move_obj:Object = new Object(); move_obj.onKeyDown = function() { switch (Key.getCode()) { case Key.UP : player_mc._y += 1; break; } } Key.addListener( move_obj ); //‐‐ method #2 – keyDown event player_mc.onKeyDown = function() { switch (Key.getCode()) { case Key.UP : this._y += 1; break; } } } Key.addListener( player_mc ); //‐‐ method #3 ‐ onEnterFrame and isDown() move_mc.onEnterFrame = function() { if (Key.isDown(Key.UP)) { player_mc._y += 1; } } EXAMPLE
22. ne Button Casual Games • Focus – user input, game play and graphics • Should be very responsive – Smooth Animations – Immediate Actions • Game Challenge – Better to have many stages/levels – Timing + Rhythm + Reaction = GAME EXPERIENCE • Key Lag – Between device platforms – Tweak timing calculations (if needed) Sample
23. Collision Detection FLASH LITE 1.1 • Flash 4 syntax • hitTest() • Primitive Math • Chapter 6 in our book FLASH LITE 2.x • ActionScript 2.0 • hitTest() available • More complexity possible • … also in 6 EXAMPLE EXAMPLE
24. onEnterFrame() • Can be your friend for Flash Lite 2.x games – i.e. Character movement, etc. enemy_mc.onEnterFrame = move; player_mc.onEnterFrame = function() { //‐‐ do xyz } • Performance – Remember call is executed X times per FPS – LIMIT multiple onEnterFrames() • Use only for more robust target devices • Flash Lite 1.1 = “frame looping”
25. Math and Physics • Limited Device Capabilities – Handsets vs. portable consoles – Memory and Performance • Avoid overtly complex game computations • Flash Lite 1.1 – supports limited Flash 5 object – Drawing API can be simulated (sort of) • Flash Lite 2.x – supports AS2 Math object – Drawing API – onEnterFrame() EXAMPLE
26. File Size • Typically no more than 500 KB for SWF • Some carriers restrict file size (KB) • Available Bandwidth – GPRS 2/2.5G, 3G, others … • OTA content delivery – Sometimes user pays per kB download • Decompression – FL 2.x SWF decompresses incurring penalty – Images, Sounds must decompress
27. Mobile Sound Device Sounds • Playback outside of Flash Lite • Smaller size • Common formats: – MIDI, MFi, SMAF, AMR, others • “Proxy Sounds” • FL 2.x device sound synch • Background MIDI Tracks • Lots of handsets support MIDI Native Sounds • Playback within Flash Lite • Larger Size • Common formats: – PCM, ADPCM, .WAV, .MP3 SONIFY.ORG: SOUND RESOURCES Articles by Hayden Porter
28. Mobile Game Text Device Fonts • Preinstalled device fonts • Results in smaller file size • Position anywhere on x, y doesn’t matter • Not consistent look & feel • No anti‐aliasing • Point Size Restrictions Pixel Fonts • Hundreds available • Larger file size • Position on x, y integer values – i.e. x=0.0, y=0.0 • Consistent look & feel • No anti‐aliasing • Use various point sizes Device fonts save space Device fonts save space Device fonts save space Use pixel fonts for look/feel Use pixel fonts for look/feel Use pixel fonts for look/feel
29. Mobile Game Graphics Bitmap Vector • “Larger” file size • Less CPU resources • More memory • Scaling/Rotating = Bad • “Smaller” file size • More CPU resources • Less memory • Scaling/Rotating = OK Vectors preserve look when scaled Pixilation occurs on bitmap assets when scaled “Versus”
30. Target Device Memory • Memory Heaps: • Static – nearly guaranteed • Dynamic • Typically 1000 KB … 0 kB and up to 6,000 KB • Fluctuates depending on other apps, etc. • FSCommand2 API var total_num:Number = fscommand2( “GetTotalPlayerMemory” ); var free_num:Number = fscommand2( “GetFreePlayerMemory” ); • Problem with Content #1: “Out of Memory” • Garbage Collection • 60 seconds idle or significant rise in memory usage • We need an API to avoid memory leaks!
31. Memory Profiling Tools “OLD” SCHOOL TASK SPY – Symbian Series Devices – Download: www.pushl.com/taskspy “NEW” SCHOOL Adobe Device Central – Static/Dynamic Heap Info – Memory usage graphing – Heap Adjustments
32. Target Device Performance • CPU • Equivalent to “Pentium PC” • Target FPS • CPU “Timer Resolution” • Nokia: 16 FPS, iRiver: 20 FPS • Other Flash Lite devices • 8 fps and up • Speed‐o‐meters • Test FPS capabilities • K.I.S.S. Principle Content = Keep It Simply Silly
33. Memory & Performance Tools OLD TASK SPY – Symbian S60 Devices – Download: www.pushl.com/taskspy NEW ! Adobe Device Central “Performance Calibration Tool” – Each device has “index” – Simulated CPU usage – Performance reporting – Only visual elements • AS 2.0 Profiling Tool http://www.nochump.com/asprof
34. • Some common screen sizes on target devices … • Adobe Device Central – Screen size searching, etc – Device “Profile sets” 176 × 208: Nokia Symbian Series 60 320 × 240/128 x 160: Nokia Series 40 176 × 220 (“204”): Verizon v3c (BREW) 320 × 240: Chumby 320 × 240: iRiver u10, Clix 1/2, u20 128 × 128: iRiver e10 480 × 272: PSP Many others! Screen Sizes
35. Pixel Depths and Color • Not all devices support the same color depth • 12‐bit to 24‐bit … typically 16‐bit • Example Devices • Nokia S40 6131 (24‐bit) versus Nokia S40 5300 (18‐bit) • Adobe Device Central • Search capabilities Color Palette may need adjusting if ported to new target device.
36. Debugging Flash Lite Games • trace() statement trace( “Got here!” ); • Toggling trace //trace( “Got here!” ); … or: • Friendly Ghost Tool • Flash Lite 1.1 • Flash Lite Error Codes • Common Errors – Out of Memory – “Bad Data” – ActionScript Stuck Orison Technologies Product
37. Optimization “Tips and Tricks” • Use bitmaps over vectors where possible • .PNG’s over .JPG’s for bitmaps • Optimize shapes and outlines • Split up and tile complex Background Bitmaps • AVOID: – animating simultaneous movieclips – complex uses of Math and looping – a lot of ActionScript contained in one frame
38. • Analyze size reports and optimize • Devnet Articles have LOTS OF TIPS! – http://www.adobe.com/devnet/devices/ • MANY MORE tricks for Flash Lite (2.x) … Optimization “Tips and Tricks” “Optimizing content for Flash Lite 2.0” ‐ Josh Ulm (Adobe) http://www.adobe.com/devnet/devices/flash_lite_optimization.pdf
39. Misc Platforms “Perhaps the hardest thing with Flash Lite is knowing the strengths and weaknesses of the each and every reference platform.” – Me
40. Flash Lite Games for iRiver • iRiver Portable Media Players • Flash Lite 1.1: u10 • Flash Lite 2.x: e10, Clix, “u20” (Clix 2G), others • D‐Click Flash Lite interface • Up, Down, Left, Right, “softkeys” are +/‐ • Capabilities: • Flash Lite Games • MP3, stored data (u10), more! • Custom fscommand2’s • Flash Lite API limitations on legacy devices
41. iRiver Clix Game • ALIEN INVASION – Casual Game – Rapid Game Development = 2‐3 days for DEMO – Flash Lite 2.0 (ActionScript 2.0) – OOP (Object based style architecture) WALKTHROUGH
42. Chumby Games • Flash Lite 3.0 Player (Linux) • WiFi enabled • Screen size: 320 px × 240 px • Sound: MP3 • User Inputs: • Touch Screen, Bend Sensor, • Light Sensor, Accelerometer • “Channels” and SWF “Widgets” • “Ultra” causal type games • Simple == better Chumby Games
43. PSP Flash Games • Download, update, configure … not preinstalled – Sony PSP ROM update version 2.70 or later • Flash Player 6 (6,0,72,27) – Reality = Think “Flash Lite 2.1” • Run methods – embedded SWF in HTML page for web browser – file:/flash/filename.swf • PSP Dev Center on Adobe – Features, Technical, DevNet Article: • http://www.adobe.com/devnet/devices/psp.html
44. Flash Lite Multiplayer games “’Turn style’ games make most sense … but it depends on your deployment environment including: operator, bandwidth, target devices, etc.” – Me
45. Multiplayer Games • What kind of games make sense? – Turn based games … Card Games, Puzzles, etc. • Challenges – Latency, Bandwidth, Billing Usage (pay per Kilobyte, etc) • Communication Methods – HTTP (Polling) – Flash Lite 1.1 • loadVariables(), loadVars(), etc – XML Sockets – Flash Lite 2.1, 3.0 • Sushi Socket Server (Flash Lite API) • Tornado – Open Source Java NIO Server • Other commercial Socket Servers – SWX • SWF like format for data exchange • http://www.swxformat.org – Flash Lite = Bluetooth • Extending Flash Lite = Kuneri Lite and Flyer (Open Source Project) Custom Socket Server … Chapter 6 Sushi Socket Server Game
46. Mobile Game Testing Emulators help … but “Rule #1: Always test on actual target handsets (when at all possible)!” ‐ Everyone in the Mobile Development Community
47. “Emulators”, Simulators, & Testing • All target devices – Adobe Device Central • GSM – Nokia 3rd Edition SDKs • BREW – Qualcomm Simulator • Others … ALWAYS TEST CONTENT ON TARGET DEVICES!
48. Mobile Game Deployment “Worldwide revenue for mobile gaming subscriptions could increase from $3 billion to $10.5 billion in 2009.“ – Juniper Research Ltd.
49. • Aggregators, Content Providers, Operators • Device Manufacturer Pre‐installation/On‐device • Memory Card, or “Virally” Game Distribution … and MANY OTHERS!
50. Wrap Up Q&A, Where to go from here?, “Future thinking”
51. Q & A • What can we do with Flash Lite 3? – Native Flash Video now supported – T.B.D. • “Wish List” for Flash Lite in the future – Garbage Collection API – Bitmap Caching – Access to Camera/Bluetooth Support – LBS Support (Location Based Services) – Self contained Player distribution files • Questions?
52. Where to go from here? • Foundation Flash Applications for Mobile Devices – http://www.flashmobilebook.com • Resources – http://www.scottjanousek.com/flashforward • – http://frame27.blogspot.com • Contact Me • Mobile Game Community flashforward@scottjanousek.com