The real story on 'Library Textures'

Since I was a new resident in SL, I'd always heard that if you want to optimize your build from a 'texture lag' perspective, make use of the Library Textures each of us are provided with.

I've heard various reasons before.... they're pre-cached.... they're optimized in some way.... etc.

Is this really true? In looking at a lot of the library textures, many of them seem to be 512 x 512. Is a 512x512 Library texture better to use than a 512x512 imported texture for some reason?

And better yet - wouldn't I be better off importing my own 256x256 texture instead of a 512x512 Library Texture?

Could someone put to rest this myth/fact once and for all?

Thanks!

If the cache (or intrest list or whatever it is that's borked) was working the library textures would probably load quicker since most people would have seen them already. However, client side it'd be betterto use custom textures to reduce the amount of video memory needed (unless the library textures are already in another build that's visible from your plot).

Thanks, AJ - I'm just trying to think what's best: assuming I'm attempting to optimize the experience for someone with the absolute minimum spec of hardware.

I agree with AJ on this one. Some (but certainly not all) library textures are performance-beneficial only in that they're commonly used, which means there's a good chance they exist in most people's chaches before they get to your build, since most people will have already encountered them elsewhere on other builds. For example, it's a safe bet that most people have Plywood and Blank cached, since those are everywhere. However, some of the less commonly used ones are no more likely to be cached than any custom texture would be.

Nothing at all is "pre-cached", as far as I know. What is and isn't in someone's cache is entirely dependant on where they recently haveve been and what they saw when they were there.

Also, I'd hardly call the library textures "optimized". Many of them are way bigger than they need to be for the amount of detail they contain. There's no need for concrete, for example to be 512x512. Concrete is a uniform enough substance that 256x256 or even 128x128 is more than enough to pull off the effect convincingly. That black & white metal grate thing is even worse. It could problably go down to 64x64 and look just as good. So the answer to your question in this regard is yes, you'd be better off using a smaller texture for things like that.

That would be true even if they were pre-cached, by the way. While pre-caching would eliminate the need for download, thus greatly increasing rez time, it would not improve overall post-rez performance. Every pixel in every texture consumes a certain amount of memory and processing power. The smaller the textures, the more of them you can see at once before you notice a drop in performance, regardless of how they happened to get into your cache. Always go as small as possible with textures.