Dynamic Updates for Videogames
Seamless and Transparent Integration of Content
and Engine Update in Online and Connected
Videogames
by Thomas Bousquet & Edouard Kieffer
Motivations & Existings Products
However none of them
provides transparent update
of both content and code
Architecture & Technologies
• Technologies : SOA
• Server (JBoss application)
– Back-end : Hibernate, Spring, XFire
– Front End : Flex
• Client
– JNotify, Webservice
Architecture: Back-End
JMS Publisher
RMI Services
JMS Manager
Controllers
Web Services
Services
DAO
Hibernate
Back-End
JDBC
MySQL
Architecture: Client API
JMS Subscriber
RMI Services
JMS Manager
Service Client
DynaCode Manager
Dynamic Objects
ClassLoader
Invocation Handler
Client API
Dynamic Classes: How Do We Update?
Dynamic Classes: Three Suspects
"Automagically"
Managed
Custom
Dynamic Class
Implicit Dynamic
Class
• Leave the migration
process to us!
• You control the
migration process
• The most flexible
implementation
• Migrate to new
version using field
reflection
• May also apply the
automatic process
beforehand
• Doesn't need to
conform to an
interface
• The dynamic class
needs to implement
an interface
• The dynamic class
needs to implement
"ICustomMigration"
• Need only extend
ImplicitDynamicClass
• ... But rather ugly for
now
Dynamic Classes: Back – Client
Interactions
• Two channels
– Client may request through RMI
– Data push emulated by JMS
• On initial connection, client requests upto-date report of dynamic classes
• If an administrator changes current
class revisions, client notified through
JMS
Content Update – Main Concept
Content Update – 1 Interface, 2 Classes
IupdatableResource
ResourceListener
UpdatableResource
Manager
• Provide renewing
• Listen to a particular
method for considered
file
• Manage the listeners
resource
and act as a
• Contains a list of
middleman for
• New implementation
registered
registering
for each 'type' of
IUpdatableResource
IUpdatableResource
resource (texture,
• New implementation
model, sound, XML
• New class inheriting
for each 'type' of
file)
from this for each new
resource (texture,
application
model, sound, XML
file)
Demonstration Time !
• Proof of concept of the applicability of
our framework to existing solution
– Java Monkey Engine
– AirCarrier showcase application
• What we will demonstrate
– Administration Interface
– Dynamic texture update
– Dynamic update of AI Manager Behavior
Evaluation
• Dynamic code :
– constant overhead for calling dynamic :
calls 6 to 8 times slower => only use on
computationnaly intensive methods
• Dynamic content
– Disk access and content renewal creates
'acceptable' stutter.
Limitation of this demo & extension
• With more time and/or a better
architecture:
– Use AMF instead of web services for back /
front communication
– Describe ressources used by object with
XML file and listen to this files.
– Extend the existing resource manager to
integrate smart cache management
What happened to C++ ?
• C++ is still the leading language for
videogame application
• Too complicated for the scope of this
project (lack of existing framework)
• Advantages :
– Function parameters as reference
– SWIG enables to automatically create
wrapper for other languages ranging from
Java to Python, Lisp and C#
Extensions - Code
• Features :
• Tools :
– Plugin eclipse to enable traditionnal
function call for dynamic code
– EJB 3.0 (abstraction of persistence)
Extensions – Content
• Features :
– Intercept message containing data written
from memory to disk to suppress disk
access.
• Tools :
– Model Oriented Programming : provide
tools to create implementation of
IUpdatableResource and IresourceListener
at once.
Conclusion
• Features :
– Intercept message containing data written
from memory to disk to suppress disk
access.
• Tools :
– Model Oriented Programming : provide
tools to create implementation of
IUpdatableResource and IresourceListener
at once.
Thanks for your attention
QUESTIONS ?