No one on the Linden side is saying WHEN we might see SSA (Server Side Appearance baking) roll out. Today at the Server Beta meeting we found one reason it is taking longer than anyone would like. I think the Lindens are ready for SSA to rollout. But, they have to get problems fixed and they have a dandy one.

SSA is in testing on the Preview Grid (ADITI). You can go into Testy Sandbox and Lagland to try it out. But, be warned, read the rest of this article first.

Corrupted Textures

JIRA SUN-74 – Apparent avatar skin and eye texture asset corruption with Server Side Appearance.

This bug is about SSA corrupting textures your avatar is wearing. Skin and eyes are definitely affected. It appears any Mod-OK skin is at risk.

When the JIRA description says “texture asset corruption” it means on the asset server. If you don’t know, the asset servers are the machines that hold the files that make up all our stuff. So, a skin or a shirt, which is made from an image file, has its file sitting in the asset servers. If that file is corrupted, it stays corrupted.

We are used to seeing textures fail because of corruption. But, that is almost always a problem on our side. The texture fails to download properly or something happens to the file in our cache. That we can fix for ourselves. We logout and clear the cache. When we log back in we get a new copy of the texture from the asset servers. Usually things are all better.

But, if you corrupt the file in the asset server, there is no place left to get a fresh copy.

How?

So, how does the texture get corrupted? Well, it isn’t all that easy, but it also isn’t that hard. If you are using a non-SSA viewer and move from a SSA-disabled region into an SSA-enabled region the texture corrupts. Think you go into ‘cloud’ mode crossing the region boundary. Then you get an error message saying and I’m fuzzy here, the viewer doesn’t understand the error message. Then you are asked if you want to SAVE the changes to clothing/body part. Save and presto the texture eats it. See opening image.

If you come back in another viewer, you see the same corrupted texture. Clear the cache and it is still corrupted.

The current thinking is this can only happen with Mod-OK skins and eyes.

Avoiding

So, using No-Mod skins and eyes when testing SSA is a good idea. If you have a Mod-OK skin you like and you use an older viewer, it is at risk.

Basically only if you use a NON-SSA viewer you can run into this problem. So, update your old viewers to a newer SSA capable viewer.

You only run into the problem if you cross from a non-SSA region into an SSA-enabled region. That is only possible in the Preview Grid, for now.

It shouldn’t be hard to avoid those scenarios.

What’s Being Done?

The Lindens have just become aware of the problem. They are just starting on the fix.

If all regions are running as SSA-enabled, there is no problem. So, this bug is delaying enabling SSA in the Snack release candidate channel and the other release channels. The Lindens will have to resolve the problem or flip the whole grid at the same time. But, no matter how they go about it. Current processes require some time. That leaves a window open for someone to get bitten.

The only other choice is to throw everyone off the grid. I suspect that is pretty much a last resort thing for the Lindens… way unlikely.

So… it may take a couple of more weeks before we see SSA. If things go well, you should never see this problem on the main grid. …but that corrupted texture might be good for Halloween…