sms game development making the most of a sucky technology greg costikyan [email protected]...
TRANSCRIPT
What Is SMS?Short Text Message ServiceBuilt into GSM from the startso everyone in Europe can “text” everyone else20 b + messages exchanged every month
Not yet successful in North America carrier walled gardens breaking down but lower prices for voice & pager/IM availability may continue to keep this smaller here
Why Develop SMS Games?
Everyone in Europe texts Comfortable with technology Perceived as cool (while “WAP sucks”) Potential large audience (and market)
Carriers & Aggregators eager for SMS titles
In North America, too, where they’re waking up to the missed opportunity
How Does it Work?a. Originator inputs
phone number & message.
b. Sends message over air to SMSC.
c. SMSC forwards message over Internet to recipient’s SMSC.
d. SMSC sends message over air to recipient.
SMSC Can Send & Receive with Game Server
User requests game by sending SMS to that number
Server is assigned a “Phone Number”
SMSC must know that phone number = server’s IP address—game service must have a deal with the carrier!
Header info identifies user’s phone number; server parses, processes, responds to user.
SMS Costs Money
Typically 10¢/message (7p in UK)
Carrier can choose to charge more or less for a game’s messages, or to charge a flat fee for a game.
Revenues shared with game serviceMarketing cost in making users aware of phone number to message
Game Should be Playable in Just a Few Message Exchanges
Otherwise will be too costly for many players
Try to keep it to <10 messages per game (or 1-3 per day for games played over a period of time)
Each Message Must Advance the Game
In most games, the result of interaction can be minor (turn left 30 degrees; a card is played). With SMS, a handful of interactions must combine to a satisfying game. A non-trivial design challenge.
Each Message <=160 Characters
That’s a =hard= limit.
Can break into multiple messages, but each costs money…That’s basically 25 words or less.
Localizing generally increases the number of characters in text.
Tricks to Help
2, not two.
Abbrev. if can keep clear.
Cn u use txting abbrevs?
Edit ruthlessly.
Put rules in separate “Help” message.Test all boundary conditions.
No Graphics Means...
Hard to show physical layout with pure text. Text adventures (N thru Door)—but a
lot of text used for navigation. Text representations (Ship 2 > 3,7)—
but hard to visualize.
Can’t Rely on a Monospace Font
This: looks like this:
CNRQKRNCPPPPPPPP........................PPPPPPPPCNRKQRNC
CNRQKRNCPPPPPPPP........................PPPPPPPPCNRKQRNC
Avoid Games that Depend on Locations
Most electronic games are an exploration of space
But it’s not true of all game styles: Word Games “Choose a Maneuver” Fighting games Tamagotchi
Hammurabi
#conquest
A Player’s Orders Are Text
A command-line environment.
Syntax Must be Transparent Syntax Must be Forgiving
Demand the least text entry possible.Allow “stackable”orders.
Latency is Off the Scale
Typically, a minute or more.
Interaction at discrete, separated moments.
Each message really must count
Dealing with LatencyTurn-based games. Round-robin Simultaneous movement
“Act whenever” games. Limited by real time
“Slow update” games.
Multiplayer or Die
Head-to-Head games
Limited-interaction large-scale multiplayer games
Handful of players
In-game messaging
“Smart Messaging”
Message concatenation (459 characters)
B&W bitmapped images (72x28)
Ring tones (single voice)
EMS: Enhanced Message Service
Message concatenation (3-6 messages)
Flip animations (32x32, 4-frame)
B&W images, max 1k (32x32)
Ringtones & sounds
10 pre-installed sounds
MMS: Multimedia Message Service
GIF89a animations, PNGs, JPEGs 640x480 in theory, in practice 174x133
Sound: AMR, WAV
No limit to message length
Punisher: The Mobile Game
www.punisherthemobilegame.comwww.riot-e.com
Botfighters
www.botfighters.comwww.itsalive.com
Fisu
www.fisupeli.comwww.smallplanet.fi
Mobile Rome
www.gripstudios.com
Doing Better
Messaging & Challenges
Persistence
Algorithmic, not Instantial
URLs
Nokia information & emulator for MMS: http://www.forum.nokia.com/main/1,35452,1_2_7,00.html (requires free registration)
Ericsson info & emulator for MMS:http://www.ericsson.com/mobilityworld/sub/open/technologies/messaging/index.html?PU=messaging (requires free registration)