When Sculpties Attack

Sculpties can be a great building tool in Second Life, particularly when you need to create organic shapes that may either not be possible with conventional prims, or would require dozens, if not hundreds, to achieve the desired effect. Unfortunately, there aren’t any rules governing their use, and as a result they often get over-used.

Over-used, you say? How is that even possible? Easy. While a sculpty only counts as a single prim for things like sim and parcel prim counts, they carry a relatively high price when it comes to computing. After some research, I’ve come to understand that a single sculpt requires the same amount of computing power on the Viewer end as rendering 12 tortured and twisted prims. Additionally, the sculpt map itself eats up a modest amount of texture memory. It’s usually tiny (under 256K per sculpty, depending on the resolution of the sculpt map used), but it’s there consuming a very limited resource nevertheless. And that’s on top of the amount of video memory that will be used for the actual surface texture. A sculpt that uses a 256x256 sculpt map and a 256x256 texture, for example, uses 512MB of video memory compared with only 256K of video memory on a regular prim using the same texture.

Individually, that may not sound too bad. And when you use them judiciously in a build, they look great and everything rezzes quickly for most visitors. But when used excessively in builds, it can increase viewer lag dramatically (each prim taking 12 times more computing power to render, and double the video memory consumption). The end result for visitors can be as extreme as causing their Viewer to crash (because the video card was overwhelmed), or more likely lower frame rates, a field of gray blobs, and untextured prims that takes an unusually long time to load. While some folks have patience and will come back, crash after crash, moving in slowly and dialing back settings & draw distance until they can get through, or on beefier machines just sitting it out and waiting the additional time it can take... most people don’t.

For my case study, I submit the photos below. Periodically, I like to try and “see the world through a visitor’s eyes” as much as my computer will allow. To do this, clear your cache and re-log into Second Life and then explore. While my current machine isn’t the latest and greatest CPU and graphics card combo, it is ahead of the ‘average’ system out there with plenty of RAM, discrete GPU & plenty of video memory and very fast internet connection. So my assumption is that the world is rezzing more quickly for me than it is for most others. It took just over 2 minutes to render the scene below (each shot is approximately 10 seconds apart).

I’m not picking on any one build (either pictured, or anywhere else on the grid). It is worth pointing out that the scene above actually shows several different builds across a number of parcels, and includes a few of my own objects as well as those of the neighbors. These photos are intended merely to illustrate the cumulative effects.