Ray J. Greenwell
3bbe3a6330
This has been happening for a while on PX and I've been meaning to track it down. When a peer shuts down an object that's proxied on other peers, the other peers receive an ObjectDestroyedEvent, and clear the object from their omgrs. Other listeners may also receive the event and will need to clear the proxying information, but that causes an unsubscribe to be queued up, which when it runs will find the DObject already gone, and log an error. At first I considered not queuing up the unsubscribe action if the object is no longer present in the omgr, but in the case that I'm working with we have 2 or more objects that will all be destroyed simultaneously. Even if I test to see if the first object is around or not, this same test would always pass for the second object even though its death event is next on the queue. The unsubscribe would be enqueued after THAT, so there's no test to detect that the two objects are linked. Instead, just suppress this message if we're a peer client. I didn't want to suppress it altogether because we might want this message logged for normal client connections. Maybe not. Perhaps there is a better way. Maybe the PeerNode should add its own ObjectDeathListener and clear out the proxy information and ensure that the proxied object is also destoyed, and clients need not unproxy manually in that case. RFC.
The Narya library
Narya provides a framework for building realtime distributed systems with an emphasis on multiplayer online games (massive or otherwise). Its various packages include:
- presents: A distributed object and remote procedure call framework for creating realtime distributed systems.
- crowd: A foundation for a multiplayer environment with notions of bodies and places, and support for chat and moving between places.
- admin: Useful administrative functionality including a mechanism for declaring configuration that can be viewed and modified at runtime by an administrative client.
- bureau: A framework for managing a network of code execution servers, which can be used to host ActionScript server-side code in addition to the Java server normally used by presents.
Javadoc documentation is provided.
Tutorials, etc.
Three Rings hosts a site called Game Gardens where the Narya library is used to develop a wide array of multi-player online games. On that site you can find tutorials and sample code relating to the use of Narya in game development.
Building
The library is built using Maven, or Ant.
The Maven build uses the standard targets:
package: builds the code and creates the jars and swcs
install: builds and installs the artifacts into your local Maven repository
test: builds and runs the unit tests
The Ant build uses the following targets:
all: builds the distribution files and javadoc documentation
compile: builds only the class files (dist/classes)
javadoc: builds only the javadoc documentation (dist/docs)
dist: builds the distribution jar files (dist/*.jar)
If you wish to build the ActionScript components via Ant, you will need to supply the location of the Flex SDK on the command line:
% ant -Dflexsdk.dir=SOMEPATH dist
Artifacts
Narya provides three different build artifacts, for differing purposes:
- narya: contains the main Java library; exports dependencies only for libraries which are required by a running client or server.
- naryalib: contains the main ActionScript library; exports dependencies for libraries needed when building a SWF using naryalib.
- narya-tools: contains the code generation portions of Narya which one need integrate into their build; exports dependencies for various libraries needed when running code generation.
Narya is published to Maven Central. To add a Narya dependency to a Maven
project, add the following to your pom.xml:
<dependencies>
<dependency>
<groupId>com.threerings</groupId>
<artifactId>narya</artifactId>
<version>1.11</version>
</dependency>
</dependencies>
To add it to an Ivy, SBT, or other Maven repository using project, simply remove the vast majority of the boilerplate above.
If you prefer to download pre-built binaries, those can be had here:
Related Libraries
Narya is extended by the Nenya and Vilya libraries which provide additional game related functionality like 2D and 3D graphics support, animated character rendering and a more sophisticated virtual world framework.
Distribution
Narya is released under the LGPL. The most recent version of the library is available at http://github.com/threerings/narya
Contact
Questions, comments, and other worldly endeavors can be handled via the Three Rings Libraries Google Group.
Narya is actively developed by the scurvy dogs at Three Rings Contributions are welcome.