With all due respect to the authors, Julian Lombardi’s comments and the original Why Second Life Won’t Get A Third article both leave out important information which ironically makes the strongest case for Croquet. The Linden Lab folk know far too well the constraints of their architecture but they also believe they can scale because they are moving away from their highly centralized model towards something more distributed - a page out of the book of Croquet. The new second life grid architecture is evolving in a reasonably open manner(see alsoDavid Jones Notes from OOPSLA). While it won’t ever be as elegant as Croquet, it will address enough of the problems to keep growing the base particularly as the business model shifts to leverage the economic infrastructure. Unless Croquet greatly expands it’s niche, it won’t become a means of creating serious alternatives to Second Life. I believe however that it can and will. In 2008, I expect we’ll see some evidence of Worldbase + Interactivity Server architecture I’ve pointed out before.

Multiple monitors and visualization are not a panacea but they do provide a lot of free, already written and debugged tools! These tools aren’t perfect but they generally don’t crash! Well, people do get sick and die, but in general, the software running our mind/body systems is very robust and stable. If I start looking/pointing to the wrong screen, I gracefully recover. For you Matrix fans, this is the “your other left” scenario. I sleep but I’ve never done a full system reboot! If I’m not sure what the best arrangement is I can put post-its on the monitors or notes on a whiteboard within view. This approach has been used for a very long time in complex systems where humans are in the loop. In the past half century aerospace and finance come to mind but the practice goes back much further to the art of memory and beyond to ancient Egypt. In the world of ubiquitous computing and locative art I call the meshverse, coding has to move beyond the text editor and even the traditional IDE - it will be come both visual and location oriented at the same time. Imagine a mash-up between the text adventure-like game playsh and Croquet annotations! I am at present working on the infrastructure for such an environment, bits and pieces of which you can see at my BOP Space and GVScript sites. Both of the previous two links are showing Squeak’s Wonderland but if you’ve been here before, you’ve seen earlier versions of the building blocks.

For the time being, I’m disabling comments here while I try to get to the bottom of what appears to be malicious tampering with the site. During this time, you may notice some entries that are blank, but I hope to have the database restored soon.

Thanks for stopping by.

CroquetHarness cleanup

Next save the image and see if the file size shrunk back to a reasonable level. If not you’ll either have to go zombie hunting or start from a clean image. Sometimes zombie hunting doesn’t produce the results you want. It may be that you’re not looking for the right kind of objects but in other cases, there are just too many zombies of different types and it’s taking a long time to figure out how to untangle them. In either case, if you don’t have any data or graphics bound only to the image, AND your code is reasonably well organized(this doesn’t have to mean Monticello - some projects can be managed well with change sets) the quickest solution may be to just dump the code and load it into a clean image. However, one often learns valuable lessons while zombie hunting so there’s good reason to learn some basic techniques.

The first steps in zombie hunting are simple “is-it-plugged-in” type of things. First look to see if any error windows are hidden from view. Then a look at workspaces you have open in the image and see if you dumped any large objects into variables while exploring. As above, save the image and then check the file size.

Next, you’ll want to identify likely candidate classes that may have instances hanging around. There are no hard and fast rules for this but I tend to look for:

• objects that open and/or initialize central or frequently used UI elements
• objects whose existence depend upon plugins
• objects making calls to any low level system
• objects created by recently loaded packages code I didn’t write

If you browse the CroquetHarness cleanup method, you’ll see a series of statements many of which look like:

SomeClass allInstances do:[:i | i doSomethingToGetRidOfMe.]

I usually get a count first:

SomeClass allInstances size

If there are a lot and you happen to know the appropriate doSomethingToGetRidOfMe method you’re in luck. Things aren’t always that simple though because you may not want to get rid of all the instances or the doSomethingToGetRidOfMe method only works under certain conditions. In the latter case you’ll need some method or script to identify suspect instances

(SomeClass allInstances select: [:z | z suspect]) do:[:i | i doSomethingToGetRidOfMe.]

Often, none of the above works because the doSomethingToGetRidOfMe was not intended to deal with a broad spectrum of circumstances but rather the ones likely to occur under “normal” use. In such cases, one needs more powerful instruments which fortunately Squeak is full of. So start out by opening an ObjectExplorer on all the instances.

Then you can use the menu to find out what objects are still referring to each instance and thus preventing it from being garbage collected:

This will open an inspector with a list of objects:

that are referencing the instance. If you’re fortunate, there’s an obvious reason why the reference still exists and a convenient doSomethingToGetRidOfMe to clean things up. However, there’s a good chance that neither exist in which case, you’ll need to call upon an experienced zombie buster or become one yourself!

HTH

Shiny Life(detailed step-by-step video tutorial)

New World Notes: Sculpties Made Simple

Plopp Second Life: Even a child can do sculpties 

3Greeneggs: Plopp has potential but flops

PloppSL allows you to create intriguing Sculpted Prims for SecondLife™ easily. Both texture and model are created in one step. Simply paint the front and back side of your model and it will be converted to a Sculpted Prim by PloppSL.

Second Plopp

Julian Lombardi’s Blog: HP Joins the Consortium!

• Getting Started: Starting Croquet
• Programming: Simple World

If you’re itching for more right now, you might try to understand what the quick and dirty path has in common with the route taken by Simple World. To do that you need to find out where and how the SimpleWorld class is used. One approach would be to open a class browser and choose Class Refs from the menu:

However, this will take you on a somewhat thorny path

that ends at a fork where you have to decide what classes to explore further but haven’t really learned anything to base that choice on. Often in Squeak, whenever there’s interaction with the UI, the most direct path to understanding starts with the morph you are clicking. You can cmd-click(Mac) or right-click (Windows) on any morph to bring up a set of icons called a halo.

Repeated clicks will drill down to the object you are mousing over.

Once you have a halo for the object of interest, use the red icon to bring up a menu and open an Object Explorer

Even without knowing anything about the protocol, you can figure out that when you drag one of these buttons out, it sends a message to CroquetMaster. Browsing that class you can see it’s purpose in life seems to be to create a Croquet Harness which is where SimpleWorlds get created

Careful observers will notice the class CroquetParticipant which is probably somehow related to KCroquetParticipant so try using the class menu

to open a Hieararchy browser and see

Once you start exploring KCroquetParticipant, you’ll see that it provides a framework to do what hard-coded methods in SimpleWorld and CroquetMaster accomplish. Hopefully it won’t be long before Matthew covers this better and expands on it but for those chomping at the bit, there’s something to chew on. You may also find the context provided by the Subsystem Overview useful.