Sculpt & Mesh: Then & Now


Folks who have been following my blog postings for a while will probably note that I’ve been releasing mostly mesh items for the past few months.  I still enjoy making sculpts now and then and the majority of my inventory is still sculpt, but there are just so many advantages that meshes have over sculpt that the additional hit primwise is usually far more worth it (and sometimes one can manage to be less primmy than if one were to use sculpts too!).

I recently dug up this old post of mine back from 2008, decrying the constant use of sculpts in clothing etc. It’s sort of funny because I can see areas where my position was hypocritical, yet at the same time it was true that the abusive overusage of sculpts (which eventually became the norm) was contributing considerably to viewer lag.

A few things remain problems, between 2008 and now:

[box type=”shadow”]

Sculpts are limited in their stitching type:

Sculpts are proprietary hacks that are severely limited by a set number of stitching types (shapes) that can be manipulated. UV layouts are always rectangular and always fit these stitching types completely in a similarly rectangular fashion. As a result, not counting some XML hackery*, someone looking to texture such an object will always be limited to only one rectangular texture that will always be applied in full to the object.

Restricting sculpts to a set number of stitching types also creates problems as far as distortion – bunching up at the poles of sculpts in particular comes to mind. Additionally, because sculpts are always limited to a specific UV layout, stretching things out too far between one or two set of verts could mean ugly texturing later.

Each sculpt represents 2048 triangles. No more, no less.
Sculpts are assigned only one prim per 2048 triangles. On the surface, this was a blessing because people felt they could be far less primmy while gaining more realistic looking objects, even if in a limited fashion. Prim hair that would be otherwise impossible given limits on the size of linksets was suddenly eminently possible. But let’s also remember that sculpts represent a minimum of 1024 quads/2048 triangles per prim, and due to the problems outlined above, in most cases it is not possible to make as good use of a sculptie as one can with a mesh with the same number of faces. Many game companies strive to keep full characters down to between 4000-6000 polygons total, yet some content creators now broach the maximum number of items within a linkset with each prim a sculpt (that’s 524288 polygons)! And that’s just one attachment! If it’s a boot, you’ll need to wear a matching set (doubling your polycount) and of course if you want to wear anything else, that will be more costly resource-wise as well. **

* Of note: there is a hack out there utilized by some content creators which gives some limited flexibility as far as adding an additional texture face to a single sculpt, however the fact remains that sculpts are mainly proprietary to Second Life and when used in other environments would most certainly be considered inflexible, wasteful and inefficient.

** For extra fun, let’s also not forget people using V2/3 can now add up to 38 attachments per attachment point now and there are a total of 30 attachment points on the avatar already. So for those keeping count, that’s a maximum 524,288 polygons per attachment, max 19,922,944 polys per attachment point, max 597,688,320 polys per avatar! It’s highly likely your viewer would crash long before you managed this, however it is important to note just how abusive this can get, especially in situations where everyone wants to look their best in front of a crowd.  This can be combatted by turning on avatar imposters and there is talk about adding visual muting functionality, but this does not remove from the fact that your viewer still needs to download this information before muting it.


Of course, I realize my development of sculptie products over many years has in itself contributed to this problem, but I would have to say that is a big part of why many of the items I make now are mesh rather than sculpt. While I have always tried to keep prim counts down and use as much of a single sculpt as possible, ultimately sculpts (even in low quantities) present artificial challenges that are far more easily dealt with when modelling mesh.

I have noticed that some newcomers to mesh have elected to simply attempt upload of unoptimized sculpt assets as mesh (since that’s what sculpts are) and I have a bit of ranting I could do on that, but it’s best kept for another post. Ultimately, mesh represents a great opportunity for creators to both create more responsibly and make it look better at the same time; it is my hope that the content creator community does not squander it.

This past Monday, it was announced that 70% of active users are now using mesh-capable viewers, with about 28% of regions in SL containing at least some mesh content. Considering it was released to the public on the Main Grid back in August, this seems like a pretty healthy rate of adoption and given this format is much more of an industry standard, it makes me optimistic for content creation to come.