Sunday, 27 May 2007

A report on initial experience with sculpted prims.

Nicholas, K.   "A report on initial experience with sculpted prims."  Proc Royal Soc  2007; 2 (advance communication ahead of printing).

Availability of sculpted primative constuction allows for a greatly-expanded repertoire of objects for the builder. Preparation of the sculpted prim is nonintuitive, and requires additional methods and skills that may not be readily available. Further work is suggested to improve access to sculpting methods. Proceeds from the sale of the developed sculpted-prim glassware should go towards future research and development of sculpting methods.

Constructing a primitive object (prim) has to this point required little in the way of preparation or skills beyond that required for day-to-day existence. Linden Lab have added an option to transform a prim into a unique shape based on a map of sorts (Fig. 1). Construction of this map is nonintuitive, and requires what appears to be a fair amount of mathematics
to translate a three-dimensional representation into this color-based map.

Fig. 1. Color-map of an object.

Methods available to perform this conversion require a knowledge of three-dimensional artistry, and an investment in the tools. One tool requires a L$ 1,820,000 capital outlay (1). Less-costly tools are available, with varying degrees of utility, and are detailed elsewhere (2).

Using the "Rokuro" software (3), a series of maps were created to model common laboratory glassware (the first objects available for study). Eleven items were created; five were solid objects, and six attempted to recreate the hollow nature of actual glassware (Fig. 2).

Fig. 2. Hollow versus solid objects.

The object maps were loaded on to the beta grid for testing. All objects were given a standard glass texture (without any alpha channel), set to 30% transparency, with low reflectivity and "brightness" bump-mapping settings (Fig. 3).

Fig. 3. Texturing parameters.
(See text for 'A' and 'B' discussion.)

Creating the object maps via the lathe tool took on the order of 5 to 10 min per object, trending towards the lower end as the author gained facility with the method.

Figure 3 shows the different effect seen with hollow ("A") and solid ("B") prims. At a uniform level of transparency, the solid prims provided a more life-like outer appearance, with the hollow objects showing a penumbra, and the solid objects presenting a clearly-defined outer edge.

Figure 4 shows the glassware on a different background; figure 5, with different lighting (sunrise), and figure 6, at night, using only ambient lighting.

Fig. 4.

Fig. 5.

Fig. 6.

Simple sculpted primative construction is within the ability of the average-to-advanced builder, using very specific tools, and and access to the beta grid for testing. Glassware emulation produces reasonable results, though the correct, hollow representation of vessels produces a somewhat-indistinct outer edge. No attempt was made to optimise texture methods, and it is acknowledged that texture map creation for sculpted prims is difficult (4). Further research is required to maximise the utility of sculpted prims; furthermore, more available (and accessible) tools for builders are required.

All of the glassware will be on sale at the offices of the Royal Society, in Tamrannoch, Caledon. These will be priced at below-upload-cost, with the set of 11 pieces sold at L$100. Naturally, proceeds from the sales will fund futher sculpting methods.

The author is supported by a new-materials grant from the Duchy of Loch Avie (LA-21-003), and by viewers like you. She has no industry support or conflict of interest to disclose.

(1).   Autodesk Maya (ex-Alias|Wavefront, ex-Silicon Graphics) was sighted at US$ 6999. Linden Lab's current officially-suported sculpted prim import pathway (singular) is for Maya.
(2).   Building forum, Accessed repeatedly, often to little avail.
(3).   Jewell, Y. Rokuro (lathe) Accessed 25 May 2007.
(4).   Krogstad, A. Personal communication.


Edward Pearse said...

Thank you for this extremely informative paper. I have started to see some examples around that aren't fruit (in fact my pirate hat that I had on this evening was a sculpted prim). Noe of the attempts at making cogs that I've seen have been succesful.

My own attempts at accessing the Rokuro software seemed doomed, as at a glance I assume the page is in Japanese and it's for a Mac.

I will see what other methods I can impliment.

Miss Hermione Fussbudget said...

My thanks as well for this report!

Mr Pearse, here is a url which takes you directly to the download page, which is in English, and which now has both Windows and Mac versions

Kate Nicholas, F.R.S. said...

Apologies, Mr Pearse, for the difficult URL citation. As Ms Fussbudget noted, the (now properly-updated) link allows one to find the software without any knowledge whatsoever of Japanese.

And yes, versions are available for both Mac OS X and Windows.

I will be most excited to see what interesting prims others may come up with.

Regards, &c

Kate Nicholas, F.R.S. said...

Oh, and if you should like a showcase to demonstrate your new-found prim prowess, I'd be delighted to report on them.

For cog-making, I have used a terribly indirect method, not involving sculpties. Somewhere I found a free cogwheel designer (for Windows, yes, but that's why I keep an old PC in the basement :) ). It outputs the cog, with specified numbers of teeth &c to an .OBJ file. One then may load that .OBJ into a modeling program (I use Poser, but many free ones accept the format as well). Once just the right gritty/steampunky textures are in place, I take a few snaps, bring those in to Photoshop, and create transparent textures. Upload into SL, apply to a flattened cylinder, et voilà!

Current Population: 2 said...

Thank you Miss Nicholas - a wondeful report.

You seem to be having much more success with your sculpted prims than I have been having with mine. I've been attempting to use Wings3D and my results have been less than spectacular, although I think that may say more about me than Wings 3D.

I'm definitely going to give the Rokuro software a go, the results look great!


Alfonso Avalanche