SL project news week 5 (2): servers, issues, viewer, SSB, deformer

Server Deployments week 5

On Tuesday 29th January, the Main channel received the threaded region crossing code previously deployed to BlueSteel and LeTigre in week 4release notes.

On Wednesday 29th January, the following updates were deployed to the Release Candidate channels:

  • BlueSteel received the server-side materials processing code – release notes
  • LeTigre received the maint-server project originally deployed to Magnum in week 3. This deployment includes the bug fix for the places / search indexing issue which occurred following the original deployment of the code to Magnum – release notes
  • Magnum received a further update to the interest list code deployed in week 4, with fixes intended to deal with issues of high packet lossrelease notes.

Reported Issues

Main Channel

A number of initial problems were reported  in the forum discussion thread, Several of which  appeared to be related to initial region caching / capabilities problems which lead to some strange initial experiences for users, ranging from teleport failures / potential viewer crashes on region crossings (physical or teleport) and  out-of-range controlled flight (i.e. avatars could continue to fly under full control when apparently at coordinates well outside the region (e.g. 320, 128, 75). These issues seem to cease once regions were correctly caching following a (protracted) restart period.

There were also some reports in the forum discussion thread that use of the estate tools to eject / teleport home / ban an avatar can lead to a region cross. However, as the reports appear to be the same / similar to previously filed SEC JIRA (SEC-1215 and SEC-1204, neither of which are open to public viewing), and may be an isolated series of incidents (others are not reporting the same problems, so they have not been repro’d outside of the affected region), there is a reluctance within LL to attribute them directly to the region crossing code.

Magnum RC (Interest List Code)

The Interest List Code problem relates to the use of bots. Originally, it had been hoped that one of the fixes deployed this week would correct the issue; however this has not entirely been the case.

Following further investigation by Latif Khalifa and Andrew Linden, an explanation of the problem is provided in the deployment forum thread. The issue has its routes in the fact that the Second Life UDP protocol requires an acknowledgement (or “ACK”) for all messages sent to the viewer. However, rather than sending a distinct “message received” back to the server for each packet received, certain types of bot append the acknowledgement to other outgoing messages. A bug in the interest list code means these appended ACKs aren’t read. This results in original data been regarded as a packet loss, so it is repeatedly re-sent to the viewer controlling the bot, leading to the huge increases of bandwidth which have been witnessed. Andrew is currently working on a fix for this issue.

Deployments for Week 6

There is currently no clear news on deployment plans for the week commencing Monday 4th February. Currently, it appears that the main-server release re-deployed to LeTigre will most likely be promoted to the Main channel.

SL Viewer Updates

Issues relating to the beta viewer 3.4.5 code have been resolved, and an updated beta viewer (, was released on Thursday January 31st – see the release notes for updates. Also released on the 31st was a new version of the CHUI development viewer, The SL development viewer rolled to on Wednesday January 30th.

An interesting issue has been noted recently by those using multiple versions of the SL viewer. When swapping between more recent versions of the SL development viewer and older versions of the code base, toolbar buttons can vanish from the viewer’s UI. The exact cause is unclear, and the problem appears intermittent (I’ve personally only encountered it once jumping between project and release versions of the viewer).

Mesh Deformer Project Viewer

Sovereign Engineer assisted with code merges for the parametric deformer project viewer with the result that the code is now merged-up to the 3.4.4 codebase with the latest release of the mesh project viewer ( on January 29th. There are apparently no functional changes to the deformer itself.

The updated shape selection options for mesh clothing and human shapes in the mesh upload floater
The mesh deformer project viewer has now been merged-up to the 3.4.4 viewer codebase. There are apparently no updates to the deformer itself with this release

This removes one of the three bottlenecks to the project as noted in the first part of this week’s reports. However, the issue of internal resources at the Lab remains a problem, although Oz Linden is attempting to address this and there may be further news in week 6.

Continue reading “SL project news week 5 (2): servers, issues, viewer, SSB, deformer”

Taking a Leap (Motion) into Second Life

While I’ve been buried in dio, working on an interactive guide to … something … Linden Lab slipped out another little surprise this week via the blog.

Reaching Out into Second Life looks at the use of Leap Motion for interacting with SL. The work is being carried out by Simon Linden, and is clearly tagged as experimental, but it shows the potential of Second Life as a platform for exploring gesture-based interactions with controllers like Leap Motion.

Nor are the Lab keeping matters to themselves. The blog post states:

If you have a Leap Motion controller and would like to experiment with the Second Life Viewer, you can find the source code for these experiments at The indra/newview/llleapmotioncontroller.cpp file contains most new functionality. The Viewer is built to work in several different modes. These modes can be used to control the avatar while flying, send data into Second Life for scripts to intercept, detect hand motions that trigger avatar gestures, or control the camera and avatar movement. To switch between these modes use the “LeapMotionTestMode” value in the Debug Settings, accessible from the Advanced menu.

Commenting on his work, Simon Linden re-emphasised the experimental nature of the work and it’s possibilities, “It’s nowhere near a real feature. But it’s certainly fun to make things happen waving your hand around … I think we’ll see some very interesting stuff in the future.” He went on, “I think there’s potential there, along with touch screens, but it’s going to take a lot of work and experiments to see what really is good or not.”

The Leap Motion device (image courtesy of
The Leap Motion device for Windows / Mac (image courtesy of

If you’re wondering why Simon has his hand cocked sideways when firing the pop-gun in the video, he’s not trying to emulate any cool Hollywood or gangster-style of shooting, the Leap Motion device sensors demonstrated a blind spot when he was testing the unit, and would not register his thumb motion if he had his thumb pointing upwards.

For those wishing to try things out for themselves, Leap Motion can be ordered from the Leap Motion website, with prices starting from $69.99 + shipping (for the USA), which does not make it prohibitively expensive. It’s also capable of being put to a wide variety of uses as Leap Motion’s own promo video demonstrates.

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