getting into building design

Hi there,
I'm sure I'm not the first one to have asked this, but I've just gotten into trying to do building design in secondlife and I'm having some serious problems. The first is when I lay prims out, they sometimes flicker like mad. How can that be fixed? Secondly, is there a snap command? some way to connect prim objects together? Finally, if neither of these are viable, is there way I can generate the prims in an outside program and spawn them ingame?
Thanks a bunch.

Depending on how you're defining "flicker", the remedy can vary.

You might be talking about what's known as "Z-fighting", which is a symptom of having two or more surfaces occupying the same space at the same time. The way to avoid it is simply to make sure prims don't overlap each other.

You might also be talking about what's called "the alpha sorting glitch". You can read more about this in the transparency guide, stickied at the top of the texturing forum. The quickest way to explain it is that when two or more surfaces with 32-bit textures on them overlap in 3D space, the renderer doesn't always know which one is supposed to be "in front" and which one is "in back", relative to the camera position. So sometimes the surfaces appear to flip-flop in space, or cancel each other out, from frame to frame. The way to avoid that is to use 24-bit textures at all times unless you absolutely, positive, need transparency. And when you do need transparency, make sure to build in such a manner that 32-bit images do not overlap each other in any close proximity.

If you meant something else, please explain.


Yes. In the editor, turn on the Use Grid function. Then, whenever you go to move a prim, you'll see a white ruler overlay appear on the screen. If you then move the mouse onto the ruler's ledger lines, you'll be able to snap the prim into place.

The ruler has three modes: World, Local, and Reference. In World mode, the ruler units and orientation coincide with the global grid. In Local mode, the units and orientation are based on the selected prim's current size and rotation. In Reference mode, the units are based on a referenced prim's size and rotation. To reference a prim, select it and press shift-G (with chat closed).


This is called linking. To link two or more prims together, select them all, and then press ctrl-L. Ctrl-shift-L will unlink them.

Be aware that there are certain restrictions to what can and can't be linked. For example, a single linkset can't have more than 256 prims in it. Physical objects cannot be linked to non-physical ones. Phantom objects cannot be linked to tangible ones, without turning the entire set either phantom or tangible. And there are distance considerations. You can find the rules explained at http://wiki.secondlife.com/wiki/Linkability_Rules


Yes and no. I'll cover the no part first. SL uses a proprietary system or parametric solids for modeling, which is a bit different from more traditional surface modeling which you may be used to. At first, SL's system feels clunky and underpowered, but over time you discover it's anything but. It forces you to use a particular kind of problem-solving intelligence, which more traditional modeling programs allow you to bypass. When you get good at using SL's building tools, you end up becoming a much better modeler, both inside SL and out. It's a fantastic mental exercise, well worth getting good at.

Until very recently, there was no way at all to build externally for SL. So 99.9% of what you see in-world was created directly in-world. There are some newer technologies, which I'll talk about in a minute, but before I get to those, I can't emphasize enough how important it is to get good at using SL's built-in tools before you try to use anything external. Having a solid foundation in SL itself is crucial if you want to work effectively either with it or for it. Master the internal tools before you dabble with external ones, regardless of how much external experience you may or may not already have.

That said, here is a list of choices for external building. These are all resident-made, by the way. With the exception of sculpt prims ("sculpties", which I'll talk about in a minute, there is no official support for external building.

Prims.blender, as its name suggests, is a Blender plugin. It allows you to create SL-style prims in Blender, and then recreate the resulting models via script in SL. You can find it free on the scripting forum.

SLTK Pro is a plugin for Maya. It allows you to create SL-style prims in Maya, and then recreate the resulting models via script in SL. It also has support for sculpt prims, which, again, I'll talk about in a minute. You can find SLTK Pro at http://www.simtools.jp/sltk/en/index.php. Note, it's not cheap.

Henshin is a program which recreates AutoCAD files SL. I don't know much about it, since I'm not an AutoCAD user. You can find Henshin at http://ai-designstudio.net/

I beleive there is also a solution in the works for 3DS Max, but I don't know what it's called, or if it's been finished. Perhaps someone else will chime in with more info on that.

Those are all the offline building solutions I know of for regular prims. Sculpties are a whole other ballgame. They were first invented for Maya, but enterprising residents have enabled their creation via all kinds of other programs. The best way to learn about what sculpties are and how to make them is to read the wiki. http://wiki.secondlife.com/wiki/Sculpted_Prims


Once again, let me stress how important it is to learn the in-world tools first. Everything else hinges on that. The offline stuff is cool, now that it exists, but it's not a necessity. The in-world tools are necessary whether you're going to build offline or not. So learn them well.

Happy building.

Chosen, do you have a library of answers that you copy and paste or are all of them made to order? You always have a whole lot of reading

Max has had a offline builder for a while now. It produces the same output format as the Blender version so you can use the same import script. http://www.windyweather.net/wp/2006/12/20/second-life-max-prims-26/

There's a second one in development, which might be the one Chosen is referring to.
http://liferain.com/downloads/primcomposer/

There's another quasi snap function in the SL builder under the create tab of the build floating menu. Under the prim icons there's a check box for "Copy Selection". With a prim selected check that box then click your little magic wand on another prim face and a copy of the selected prim will rez up against that face. Well, most of the time anyway. If theres any cuts, tapers or other prim modifications your "snap" accuracy will vary.

I've been having issues with Z-fighting myself.. I built a 4 story tower with a 16x32 footprint on a 512 parcel, using only 10 prims.. all of them being the exact same size (16x32x0. and because I can not edit them (megaprims) I am getting this flickering at the intersections. I just thought about this, if I nudge each one .010 away from it's arguing edge, that should do it.. But then wouldn't I technically be crossing my property lines?

Heh, I wish I did have a library like that. I know, I know; I'm long winded. I'm trying to get better at concision. In my family, we were all raised to be prolific writers. It's a challenge to figure out how to undo that. I think I'm improving, though. See, this post is only seven sentences.

Thanks a lot Pygora and Chosen! Chosen being a prolific writer is a great thing . Anyway it's mainly with the z-fighting. Basically whats happening is I've been putting prims together, but when I modify one prim (ie. taper, twist, etc) and then try to align it to another, I'm looking at that horrible z-fighting flicker and I can't seem to align them just right to avoid it. I'm going to try snapping it to the grid and see how that goes.

There are a couple of Youtube videos on using the grid. 5 minutes and you'be be a pro

Chosen, dear Chosen...you are NOT long winded. Just prolific, and always informative.