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Some models that have been built using Sketchlife.
This is an interim model of Hackett Hall, based on this model and another model I had, where the colonnade is more detailed. These are by Michael and Chris.
This is a view of it inside SketchUp:
And this is how it looks in Second Life:
The next image shows some more detail. Here, in SketchUp, the prim edges are drawn, so you can see how the arches were done. There are three path-cut, hollow Cylinder prims making up the arches, and several Box prims making up the rest of the wall. It's trivial, in SketchUp, to align them to be all in the same plane. There are no flashing z-buffer fighting issues for the overlapping prim faces, because they are all wrapped by the same texture (this is quite easy to do using the Sketchlife bucket tool, and almost impossible to do using Second Life's native tools).
This was built for the Tutorial. At first, I didn't realise that a vehicle must be a physical object, which has a prim limit of 32 placed on it. So this original model, with 139 prims, cannot be a vehicle. However, then I reduced the prim count to 32.
Note that all of these are prims, of Box or Cylinder variety, with specific shear, taper, path-cut and hollow parameters.
Храм Василия Блаженного, the Cathedral of Vasiliy the Blessed, has been modelled by Arrigo Silva. Here it is on the 3D Warehouse. Now that is a truly wonderful model. It was done very efficiently and it looks fantastic. Anyone who has 3D modelling experience would appreciate how much work went into making these textures.
These snapshots are from inside SL when the cathedral was in the sky above UWA. Thanks to Western Australian Supercomputer Program (WASP) and Paul Bourke, St. Basil's Cathedral is now hosted on the ground, on WASPland.
Teleport: click here (this is a SL-URL).
I took this building to import, because I was fascinated by it ever since childhood, and it has always been an instantly recognisable and unique building, but I never understood its shape and how it works.
It's not a simple building, geometrically. So it is a good test for Sketchlife. Sketchlife performed reliably, per specification. After this model, I'll be surprised if there is a major problem found in Sketchlife.
Everything, except the domes and crosses, has been re-made using Sketchlife prims, mostly tapered and sheared Box-type prims, but also a number of Cylinder-type prims.
The domes, and the crosses on top of them, have been done as sculpties. I used Blender, and followed Amanda Levitsky's tutorial. (Note that in the latest version of Blender, the UV Face Select mode has been merged with the Edit Mode, so select all faces in the Edit Mode, then press "U" to unwrap.) The new Shrinkwrap mesh modifier, as well as editing the sculptie image directly in The GIMP, helped me with the crosses.
Perhaps from Second Life's point of view, the best way to make this building would be from a few large Box-type prims, and a moderate number of scupties, which would take care of parts with the more complicated geometry. In terms of rendering speed, sculpties are worse, since each one is a whole lot of quads for the graphics card to render. But we may ignore that. In terms of download speed, sculpties are slightly worse, assuming the same texture fidelity — I could make less use of repetition. Sculpties would be a better option if I was allowed to use sculpties up to 30 metres in size.
Sculpties are much better if you are close to the prim limit on your land.
The most important concern is that I don't think a tool is available that would let me create sculpties to make this model as fast as I could make it out of Box and Cylinder prims with Sketchlife.
The cathedral measures approximately 50×50×60 metres. Sketchlife has no problem working with large distances like these.
Prim alignment is, for all intents and purposes, exact. If you look closely, you may notice that some of the prims of the central tower are slightly out of place. That's not Sketchlife's fault, it's mine — I was moving them around without taking proper care when positioning.
Now, the "mostly-out-of-sculpties" approach (which I didn't use, but discussed above) may be feasible if we had suitable software — which is theoretically possible. One important advatage of it would be more freedom from those nasty glittering pixels. When I orbit around the model, they are showing through between the edges of prims. The reason is that, in some places, many prims must be used close to each other, and reduction of level-of-detail at a distance, or something to do with the z-buffer, causes these pixels to appear, even if "physically" they belong to faces which are completely blocked from view by other faces.
I don't have a very good solution against these. There are some ad-hoc techniques that one learns during modelling, and this applies equally well to building in-world, as well as offline.
Some techniques are:
I find that some clean-up post-import was a good thing, because moving around a prim by 1 metre along an axis, painting its hidden faces, them moving it back, is easier using the Second Life viewer, than in SketchUp. That is partly because you can see where there are problems and you can eliminate them on a case-by-case basis. SketchUp renders things differently. Now, positioning them in the first place, sizing them, and making them the right shape — those are much easier in SketchUp.
After importing this model, I have adjusted the cost of using Sketchlife such that it is similar to the cost of texturing: there were about 70 textures needed for this model, and just over 1000 prims, so I made the cost L$1 per prim. The complete production cost, given the current exchange rate, is therefore about US$7, which is much smaller than the cost of labour (i.e. the time investment).
As for the time investment, I spent about a day making the sculpties for the domes and the crosses and their textures. This involved learning sculpties for the first time. And I spent a day using Sketchlife to recreate the rest of the cathedral as prims and transfer the textures. It is now the third day, when I did a few touch-ups and am writing this summary.
I would have liked to get rid of more of those glistening pixels, but am now getting diminishing returns, and will treat this as a learning experience to model once, model right, in the future. By the way, glistening pixles don't just happen in Second Life Viewer, so it's nice to keep in mind.
Here are some technical views. Here you can see the individual prims.
The domes are modelled as Box-prims, which are converted to sculpties post-import.
Shown above is the way I did the arches. Again, there is no problem with flickering, because the texture is projected homogeneously onto the face with the arches.
To help with the prim count, the same prim forms the feature on this, and the opposite, side of the tower in many cases.
The following is an X-Ray view in SketchUp. This is very useful for when you want to snap to a point inside some prims.
In the following, I have selected two prims used to make a tower barrel: each prim contributes three faces.
Here are some more prims selected.
And in SL.
To summarise, SketchUp and Sketchlife allowed me to manage this quite complicated model, and to finish it in a reasonable amount of time. I would not have attempted it using the standard building tools available in Second Life.
Evgeni Sergeev
Wednesday 15 July 2009 01:27 (Western Australia Standard Time)
