For the last couple of months I’ve been working on a new project in my spare time. Dopplr is a social network for frequent travellers, designed to increase the amount of serendipity in the world. It lets you share your travel plans with your trusted fellow travellers, and uses them to find the coincidences, near-misses and surprises. Maps, mobile, timelines, feeds, calendars: you can have the information pretty much any way you want it.

Dopplr’s still invite only, but there’s a good chance you know someone with an account by now. We’ll be issuing new invite tokens from time to time, so keep an eye out. There are some screenshots on Flickr, and alpha travellers Stowe Boyd and Roo Reynolds have written some illuminating reviews. I’ll be at XTech in Paris in May (don’t forget, online registration closes soon) so track me down and I’ll give you a demo.

I’m having a great time making something of my own and collaborating with people whose skills and opinions I trust and respect. I showed the alpha release around ETech and SXSW and got some great reactions. We started inviting people in to test the app, a few at a time, and their feedback has been very encouraging.

Because I’m having so much fun and I want Dopplr to be as good as it can possibly be, I’ve taken the decision to suspend my freelancing and work on it full time. It seems they’ll let anyone be a CTO these days.

If you want to follow our day-to-day progress, I’m collecting dopplr-related links and coverage on del.icio.us.

Many people find the creation of 3D models in SL to be rather tricky. This is because there’s no built-in way to import polygon data as a mesh of 3D coordinates from an external modelling tool. Imagine if there was a factory object that could read a list of coordinates and spit out the results straight into the world, like a virtual 3D printer. As part of this project, I’m working on exactly that.

Update: As I suspected, I’m not the first to attempt this kind of work, although it looks like I’m only the second or the third. Although I had a good look around before starting to code, it wasn’t until I published this post that a couple of people contacted me to point out this Second Life forum post which provides a scripts for doing much the same thing.

To try out my new system, I went looking for entertaining test data. I have fond memories of Quakeworld – it was the first multiplayer online game that I spent a lot of time playing, and it got me through my finals. Remember this guy?

There are plenty of handy tools out there that can unpack the Quake data files and extract the models into easy-to-parse polygons formats. So, here’s my Second Life test rendering:

There’s plenty of work still to do, and lots more to say, but I’ll leave it there for now.

After Foo Camp, I’m planning to stay in San Francisco until at least mid-October, and (having worked my arse off for the last couple of months) I’m going to be able to mostly treat it as a holiday.

Shockingly, I’ve never visited San Francisco before, so I’m looking out to my extended network for fun people to meet, exciting companies to visit, and places to stay in SF.

If anyone has a housemate who’s going to be out of town, a geek apartment they want to sublet or just a comfy couch they can lend me for a few nights, please do let me know. Tips on cheap hotels also very much appreciated.

This is going to be so much fun. Hope I see you in California.

I’m only publishing the LSL code, because the serverside code isn’t very interesting and does pretty much exactly what it says in the previous post. If you want to run your own flickr screen, the URLs in the code below should work just as well for your objects as they do for mine. If you have problems, let me know. I reserve the right to switch off the code if the traffic gets too high, but I’ll post here if I have to do that.

UPDATE: Sorry, but I no longer have the server capacity to run the backend for this service. I’m told that new features in the Second Life Viewer mean that you can achieve the same thing now with Shared Media.

The code uses SL’s streaming media feature to load the jpeg into a texture. This comes with a number of restrictions: ‘You are allowed one movie (or “media” resource) per land parcel. The movie will be played by replacing a texture on an object with the movie. Users will only see the movie when they are standing on your land parcel. Otherwise they will see the static texture. Script functions only work for objects owned by the land owner or deeded to the group that owns the land. (Remember to set asset permissions on your script and object as well as sharing it with the group!)’. I’m hoping for much better media support than this in future Second Life versions.

// A place to remember the ID for the latest http request we made, so the callback doesn't process out-of-order responses
key http_id;
// Test pattern - Used as default video texture when one is missing in parcel media
key VIDEO_DEFAULT = "6e0f05ad-1809-4edc-df29-fae3d2a6c9b8";
// Set the texture to the jpeg provided by url
seturl(string url)
{
key video_texture = llList2Key(llParcelMediaQuery( [PARCEL_MEDIA_COMMAND_TEXTURE]), 0);
if(video_texture == NULL_KEY)
{
video_texture = VIDEO_DEFAULT;
llParcelMediaCommandList([PARCEL_MEDIA_COMMAND_TEXTURE, VIDEO_DEFAULT]);
}
llSetTexture(video_texture,ALL_SIDES);
llParcelMediaCommandList([PARCEL_MEDIA_COMMAND_URL,url]);
llParcelMediaCommandList([PARCEL_MEDIA_COMMAND_PLAY]);
llParcelMediaCommandList([PARCEL_MEDIA_COMMAND_AUTO_ALIGN,TRUE]);
}
default
{
state_entry()
{
// set a default jpeg
seturl("http://www.flickr.com/images/flickr_logo_gamma.gif.v1.2");
// start listening for nearby speech
llListen(1,"",NULL_KEY,"");
// start sensing nearby agents once a minute
llSensorRepeat("",NULL_KEY,AGENT,10,10,60);
}
sensor(integer num_detected)
{
integer i;
for (i = 0; i < num_detected; i++)
{
// ping the server so we know who's around
string url = "http://www.hackdiary.com/secondlife/experiments/seen?name="+llDetectedName(i);
// but don't record the request ID, because we don't need
// http_response to care about this request
llHTTPRequest(url,[],"");
}
}
listen(integer channel, string name, key id, string message)
{
llSay(0,"Setting the tag for "+name+" to "+message);
string url = "http://www.hackdiary.com/secondlife/experiments/set_tag?name="+name+"&tag="+message;
llHTTPRequest(url,[],"");
}
touch_start(integer total_number)
{
// ask the server for a jpeg appropriate to the agent who touched us
string url = "http://www.hackdiary.com/secondlife/experiments/sensed?name="+llDetectedName(0);
llSetText("Finding a picture for "+llDetectedName(0),<0,0,1>,1);
llParcelMediaCommandList([PARCEL_MEDIA_COMMAND_STOP]);
http_id = llHTTPRequest(url,[],"");
}
http_response(key request_id, integer status, list metadata, string body) {
// make sure we're processing a response we care about
if(request_id == http_id) {
// only on request success
if(status == 200) {
// data is coming back as pipe-delimited
list data = llParseString2List(body,["|"],[]);
// url is the first field
string url = llList2String(data,0);
if(url == "UNKNOWN") {
llWhisper(0,"I don't know what kind of picture to show you.
Type '/1 sometag' to tell me what tag to search for on flickr and I'll remember it.");
} else {
// name is the second field
string name = llList2String(data,1);
llSetText("Showing a picture for "+name,<0,0,1>,0.5);
seturl(url);
}
}
}
}
}

I won’t be taking on any more commercial projects until I return to the UK at the end of the season in May 2006. As always, do email me before then if you have interesting things in mind. The nearest airport is Geneva; if you’re in the area, get in touch, hop on a shuttle bus and drop in for a cup of tea.

I’ll be sad to leave the company of so many informed, intelligent and engaging colleagues (to link just three), and more than anything I will miss my team. Paul Clifford, Matt Patterson and Matthew Wood are three of the most talented individuals I’ve ever worked with.

What happens next? I don’t know. I haven’t yet arranged a next step. Perhaps you have interesting work for a software designer and developer, in which case you should email me to talk about it right away.

Here are some things our department has done that have been written about in public:

• SMS and Radio One
• MMS on the BBC website
• Releasing content for downloaded in unencumbered MP3 format
• Redesigning Radio 3′s online presence to fit the way the web works
• Making radio shows available online for streaming

$ gpg --gen-revoke 6382285E

6382285E is the ID for my key. You’re asked if you want to provide a reason for the revocation (key comprised, superseded or no longer used) and an optional free-text description. After supplying your passphrase, an ascii-armoured key block is printed out. Paste this text into a file. In my case, it looked like this:

-----BEGIN PGP PUBLIC KEY BLOCK-----
Version: GnuPG v1.2.4 (GNU/Linux)
Comment: A revocation certificate should follow

iGwEIBECACwFAkAKbmwlHQJLZXkgd2FzIG9uIGEgbGFwdG9wIHRoYXQgd2FzIHN0
b2xlbgAKCRBQw2pwY4IoXlv4AJ0XgWhSuSwv2jpd2ifFA5IXyijnEACfXfn/qtfq
KyMdShD0odXAliKD43w=
=mRL+
-----END PGP PUBLIC KEY BLOCK-----

This step could be performed when you first generate your key, and the results stashed in a safe place for later use if you lose it. In my case, I’d kept a backup copy of the original keypair, so I was able to generate a revocation after the event.

$ gpg --import my_revocation.txt

Issuing this command imports the revocation into your keyring, revoking your key.

$ gpg --keyserver pgp.mit.edu --send-keys 6382285E

This send the revoked key to the public keyserver at pgp.mit.edu. If it succeeds, you’ll get the message ‘gpg: success sending to `pgp.mit.edu' (status=200)‘. If you check your key’s verbose index page on pgp.mit.edu, you’ll see *** KEY REVOKED *** on the first line of the details.

For the record, my new key has the ID 097891DA.

Update: I just found the official word on how to do this. It’s in question 4.17 of the gpg faq.

I’ve blatted my savings and ordered a shiny new replacement, but until that arrives I won’t be able to properly finish any of the code I’ve been working on. I’m looking forward to posting a new RDF scutter based on an updated version of the foaftool code posted here a few weeks ago.