With this turn of events, and realizing that my stash of cash from previous software contracting is not inexhaustable, my search for something to keep red beans and rice on the table has now gotten me to developing applications for the iPhone.  Still having a great love for playing with OpenSim, I have been looking for some way to bring these two activities together.  That has resulted in the creation of a new project which will generate a series of posts of which this will be the first.

Maria Korolov left a comment to a prior post regarding an iPhone app which received streaming video from an OpenSim world.  That would be a great app, but just a bit complex for a first try.  Instead, I am going to embark on the development of an app which will tell me who is on my OpenSim world.

To the extent possible, it is desirable to limit interrogation of an OpenSim instance to what is contained in its database.  The reason is that a completely separate application can be created on the server hosting the OpenSim instance which can access the database.  In this way, no code modifications and additions need be made to the OpenSim code itself.  This is desirable since the folks at OpenSim keep turning out new versions every few months.  Downloading the new version of OpenSim, then once again adding code to it can be something of a hassle.  However, each time you upgrade OpenSim, you keep the same database that the previous build had.  Since the evolution of the database schema seems to have more or less stabilized with OpenSim upgrades, the separate application used to access the database need not change as a rule.

This does present something of a problem for xorgrid, however.  Information as to which of the users who have an account on xorgrid can be read from a table in the database.  The problem is, except for me, the only people who get on xorgrid do so by means of hypergridding.  There doesn’t seem to be any information about hypergrid visitors in the database.  That information is held by objects created by the code, and is not persisted.  So, at least this first iPhone app will only tell me if one of my accounts is active, which I will sort of already know.  Still, the project will have its value as yet another learning experience, and may yet spawn some other ideas which can be exploited later.

The project will thus have two components.  One will reside on the server which is hosting xorgrid and will receive requests for information over the internet, in response to which it will access the OpenSim database and return the results.  The second will be an iPhone app which will connect over the internet to the xorgrid server, request information, and display it on its screen.  This app will actually reside on my iPod Touch, but could well be installed on an iPhone as well.

There are a couple of possibilities for the application running on the server.  Perhaps the simplest would be to get the webserver running, set up port forwarding to allow web access, and just create a web page.  For privacy sake, a login page could be added so the whole world couldn’t see who is running around on xorgrid.  This would eliminate any need to write something for the iPhone, since it and the iPod Touch come with Safari, Apple’s web browser, already installed.  Sort of takes all the learning out of the learning experience, doesn’t it?

So, the first step will be to crank up Visual Studio Express (you don’t think I would actually pay for Visual Studio do you?) and whip out a C# application with a server socket and an ODBC connection to OpenSim’s MySQL database.  I’ll be doing that during the coming week and give you a report in my next post.  Those of you faithful readers who have been with me for a while will recall that xorgrid runs on a dedicated server which is one of several computers connected to the internet through a LinkSys router, and uses dynamic DNS to maintain a permanent domain name.  This will result in the need to edit the port forwarding in the router, and I’ll talk about that as well.

The displacement can be a bit tricky, and the Second Life LSL Wiki says that it is not exactly the same for male and female avatars.  The best way to set it seems to be to start the vector at <0.0,0.0,0.0> then adjust it and see where the avatar is sitting with respect to the bench.  It turns out that the adjustment is not quite what you would think.

The rotation type is a four element object called a quaternion, and setting it directly is rather complicated.  LSL has a conversion function which simplifies that.  That function is llEuler2Rot().  This function takes a vector which represents rotation about the x, y, and z coordinate axes of the sitball, with the angles expressed in radians.  Alt-printscrn won’t show these axes when you have the sitball in editing, so I’ll just tell you that in the images below, x is pointing out from the bench in the direction you expect the avatar to face when sitting, y is pointing to the avatar’s left, and z is pointing up.

Here is Ingemar trying to sit on the new pew I built for the chapel.  The inset is the sitball’s script, showing no displacement and no rotation. C’mon, Ingemar, a Lutheran Gottesdienst isn’t supposed to be that uncomfortable.  The first thing we need is a rotation about the y axis.  That axis is horizontal, and the positive direction points to Ingemar’s left.  The Right Hand Rule applies, which means that a rotation of -90 degrees, or pi/2 radians, is called for.

Now, that is an improvement, but next we have to get Ingemar up off the floor.  A displacement is called for, and you would think that this is a displacement in the z direction, since that is supposed to be up.  Actually, it’s not.  Take a look at the next picture, and look where the displacement actually is.

Look at the vector in the first argument of llSitTarget().  Notice that it is in the x component, not the z component.  And, it is -0.8, not +0.8.  Still, it gets Ingemar elevated properly.

The final step will be to move the sitball back a little so Ingemar can lean back against the back of the pew.  I’ll just do that by repositioning the sitball.

There we have it.  Ingemar is sitting right, although I hope he is not too uncomfortable sitting with that ball up his rear!  There is room for another avatar on the pew, and I’ll just copy the sitball to the other side of the pew, then link everything together.  The final step will be to copy enough pews to fill the chapel.

OpenSim has a problem which I hope will soon be fixed.  When an avatar tries to sit on somthing, it ends up sitting in the middle of it.  Take a look at Ingemar as he tries to sit on this park bench.

Turns out that there is a workaround for this, which amounts to putting a transparent box on a chair, or in this case a park bench, and letting the avatar sit on that.  Below you can see how this park bench has been modified by the addition of three such boxes set next to each other.  They are made partially visible so you can see their placement, although in practice the transparency of each would be set at 100% in the edit dialog.

The boxes are made this big so that when they are completely invisible, and you try to sit your avatar on the park bench seat, you can’t help right clicking on an invisible box instead.  Ingemar is sitting inside the box, but once the box is made invisible, it looks as though he is actually sitting normally on the park bench.  Now there will be three seating positions on the bench and three avatars can sit side by side.

One other thing, though.  If you use this approach, you will have to rotate the boxes to make the avatar sit properly.  In edit, rotate a box so that the red position arrow points in the direction you want the avatar to face when sitting.  If you were to edit one of these boxes, and select Position in the edit dialog, you would see the red position arror facing out, the direction Ingemar is facing.

This fix is not without its problems however.  When you select “Stand Up”, the avatar will leap high into the air and come down somewhere in the vecinity of the park bench.  That will have to do until our friends at the OpenSim Project get around to this little problem.  You will be able to tell when they do, because all of a sudden avatars will all be hovering over the chairs instead of sitting in them, because they will then be sitting properly on the invisible boxes.  When that happens, just delete the boxes.

Ingemar is relaxing in the newly furnished patio.  Patio furniture and some bar items courtesy of Zonja Capalini’s free-to-copy items.

Here you see the newly finished but as yet unfurnished chapel, complete with stained glass window.  The pews will take a bit of doing, so they will not be in until next week.  OpenSim still has problems with where you sit on an object.  The avatar seems to have his bottom placed at the center of the object.  The trick seems to be to add an invisible block around the chair, the center of it being where the avatar is to sit.

There is some new furniture in the visitor center, courtesy of some free-to-copy items Ingemar picked up in Nibiru, courtesy of Tiffiny Sicling

Here you see an interior view, including a reproduction of the famous painting of rubber clocks by Salvador Dali, Ingemar’s favorite painter.

The office, located in the second floor of the visitor center,  hasn’t been neglected either.  Office furniture is also more free-to-copy items from Nibiru.

There are two more building sites in this small complex, and with a little luck, at least one of these should be finished by next week.  After that, I want to get back to some more technical details when there is time.  I want to add a visitor log, and it needs to be sufficiently modular so that when the next version of OpenSim comes out, I won’t have to graft it in.  Doing it with scripting is a lot more work for a lot less functionality, but at least it doesn’t have to be reinserted into the OpenSim code in the next update.  The best way seems to be to use scripting to do HTTP access to my webspace, where information can be stored in the SQL Server instance there.

Now that I have gone headlong into the development of iPhone and iPod Touch applications, I think that there has to be a way to integrate them into OpenSim in some useful way.  It’s doubful that there will ever be a version of the Hippo viewer running on iPhone, but at least iPhone apps can do HTTP requests.  If you have any thoughts, leave a comment.

That’s it for this week.  Once again, if you are into hypergridding, drop in to xorgrid when you have time.  The Helicon region is open for anybody’s building.

A couple of anomalies have been experienced in xorgrid lately.  One is that for some reason I don’t quite understand, when hypergridding in one lands not in Helconia, at the southwest end of the island, one lands in UpperSide instead, and sees this:

Not much in UpperSide except this, so use the map and teleport south, or just fly.

The region which is supposed to be open is the one with the port number which is the same as the published listening port for hypergridding, in xorgrid’s case being 9000.  That is the port number for Helconia, and it is the port given in the [Network] section of Opensim.ini as the network listening port.  UpperSide, the region you actually land in, is given port 9007 in its terrain file in the Regions folder.  This is a bug to be traced when I get time.

My friend from Second Life, Athena Python, hypergridded in today, landed at UpperSide, and looked around to find an island that shouldn’t be there just to the north of this location!  It was a small island, and there was a nice sailboat moored to it!  Of course, xorgrid doesn’t have such an island, and she could’t get over to it.  She had entered via her new account on ReactionGrid, so presumably this somehow was left over from it.  Unfortunately she didn’t do an Alt PrintScreen and save it, so I can’t show it to you here.

I have had time to do a little building, and below are three views of the new visitor center and the buildings going up around it.

Here you see the street entrance and a view of the dock.  The next photo is a view from the patio.

Finally, a view showing the stairs to the second floor.

There is plenty of building space in the vicinity, so let’s see what you can do.  We’re still reachable from ReactionGrid, but unfortunately I tried from OSGrid earlier today and a search for xorgrid in the map didn’t turn up anything.

I plan on putting a big table and chairs on that corner patio, but that will have to wait until the next version of OpenSim comes out.  Seems that when you sit on something, you still end up sitting in the middle of it.   Sort of makes furniture a waste of time at the moment.

One of the projects that I’m planning is a big space station, which will hover high over the central region, Kraton.  I had one back when I had a world on OuterWorlds, and have always wanted to build another one.  I hope to get some progress with that sometime during the summer.

Greetings tonight from the Arrabal Tango Club located in Zonia Capalini’s fabulous Condensation South region.  The decor is quite elegant, but the bar tender seems to be occupied elsewhere.  I started my hypergrid journey in xorgrid, made a stop at opensim.mydyn.de:9090, and upon arrival zoomed the map out only to find one of the Condensation regions on the map.  I transported here and had an extensive look around, finally ending up here.  After that long journey, I could really use a stiff drink.  Just where the hell is that bartender, anyway?

My sincerest thanks for this most exquisite build.  I hope this visitor will return more often, and perhaps leave a comment on this blog so we can know who to thank.  In the background you can see the beginnings of Helconia Village rising up, and on the left, a cone left by our second visitor.  At the bottom of the picture, the black hemisphere you see is the top of Ingemar’s head.

Now a bit of bad news.  Hypergridding in general doesn’t seem to be doing so well this afternoon.  Last night I was able to make several teleports to opensim.mydyn.de:9090 but this morning it was no go.  Wanting to find out if xorgrid was at fault, I went to ReactionGrid and tried to teleport from there.  No such luck there either.  I also found that ucigrid04.nacs.uci.edu:9003 was unreachable both from xorgrid and ReactionGrid.  It continues to be possible to reach xorgrid from both ReactionGrid and OSGrid, however.

You may recall, if you have been reading this blog for a while, that in a previous post I gave some directions of how to configure settings in the [Network] section of OpenSim.ini for running OpenSim behind a router, and using dynamic DNS. This section of OpenSim.ini is where the URI’s for the UGAIM servers are set.  I had set the IP address to the server’s address on the router’s private network, which is 192.168.1.101.  Port forwarding had also been set up so that incoming requests to xorgrid.ath.cx would be forwarded to the corresponding ports on 192.168.1.101.  While that setting has worked when hypergridding in, it apparently is not sufficient for hypergridding out.  Unfortunately, I overlooked the fact that the URI settings in the [Network] section are forwarded to the remote hypergrid destination  when teleporting out.  The remote OpenSim instance can’t access xorgrid with those URL’s.  It bacame obvious that this was the problem when, having teleported to the German world, placing the cursor over Ingemar’s avatar showed him to be “Ingemar Zenovka @ 192.168.1.101″.  The problem was fixed by replacing the internal address 192.168.1.101 for URI’s in the [Network] section with the expected xorgrid.ath.cx and appending the correct port.  After that change, Ingemar ceased to be a ghost anymore while in Germany.

In other news, some actual building is now going on in xorgrid.  Helconia Village, a small piece of the Helconia region, is now Ingemar’s private building area, but the remainder of Helconia is still open for all visitors to build.  A fair amount of work has been, and will be, expended in getting that small piece built up so I made Helconia Village off limits.  As for the rest of Helconia, it’s open so enjoy!

Recently the world was upgraded to OpenSim 0.6.5, so I wanted to see how that would work with outgoing hypergrid teleportation.  I first tried some URL’s for open hypergrid sites listed on the OpenSim website, but most simply couldn’t be found when searched with the map.  The bridge site at ucigrid04.nacs.uci.edu:9003 wasn’t accepting hypergrid teleports, but it wasn’t accepting them from ReactionGrid today either. Finally, I tried opensim.mydyn.de:9090 and found that it showed up on the map.  Once I teleported there, I arrived as a ghost (actually “ein Geist” since I was in Deutschland), rather like what happens on Second Life occasionally when the sim you log onto is running slow.  Only this time, Ingemar’s corporeal existance never arrived.  It was a pity that no one else was arround at the time.  I always wanted to shriek “Booooooo” at some other avatar when that happens.  Clicking the Teleport Home submenu item under the World item on the main Hippo viewer brought me back again, but I was still permanently a ghost.

Eventually I am going to have to unleash the pursestrings, and move the dedicated server that xorgrid is running on to a dedicated highspeed access, and get a real domain name.  For now though, if you’re planning to do a virtual world performance of Dickens’ “A Christmas Carol”, I can do a great “Geist of Weinachtszeit Past”.  Booooooo, y’all!

Our first visitor, Maria, mentioned that she has had problems teleporting from OSGrid regions to xorgrid and indicated that there might be an incompatibility between the two server versions causing a browser crash.  That incompatibility between server versions may have been the cause of the xorgrid crash which occurred about the time she hypergridded in as well.  Apparently with my version of the Hippo viewer and with xorgrid running the new version, the problem is either gone away, or hiding and waiting to bite later.

If any of you have problems hypergridding in, please leave a comment.  This sort of information is quite valuable.  For now I want to proceed to build up xorgrid a bit, and of course, I remind you that the Helconia region is fully open for visitor building as well.  And, that includes the area near the dock where some streets have been laid out.  Have fun.