Big Prims - Mainland

Is possible/permitted to rezz/keep prims bigger than 10m in Mainland?
I read somewhere that is not but is see all ppl around me doing it with no problems.
What’s the real catch?

within reason

It can be done, if done responsibly. I personally wouldn't go above the 20x20x0.5 and I'd make sure that they stay within my own boundaries. Yes, I use these for walls, floors and such. Cuts the number of prims down by a lot.

Use them sparingly, keep them ENTIRELY within your own property lines and make them phantom. The Lindens will usually leave you alone if you use them carefully and wisely.

The 'catch' is that if anyone complains about your megaprims, the Lindens may remove them without any warning or notice. But as long as no one complains, you're OK if you use them carefully and responsibly.

But I want use them for skybox flors. They must be phantom?

Two catches: First, LL will remove them if they cause any problems (usually, encroaching on other parcels or causing lag--which can happen if they're not phantom; other problems have been reported, but I can't confirm them aside from their inherent inability to have a consistent collision envelope--like they can't be really hollow, for example.) Second, at least some of the larger ones are likely to just disappear without replacement when the new physics engine comes to the main grid.

For skybox floors, you probably won't see any lag effects with non-phantom 20x20s or even larger--as long as you don't teleport into the middle of one. Just be very, very sure they never get set physical!

Oh, also: they're tricky to rez on top of, so that can be a problem with floors. Some will also confuse the cam, if you anchor on them. (But there are lots of "standard size" prims that exhibit both of those behaviors, too.)

I'm on the mainland. I've found megaprims to be VERY useful...our build is on hilly land, so we've had to terrace a lot. Megaprims make great terraces and foundations. Not to mention paths and roadways. And roofs and walls for large structures. And skybox bases.

Ours aren't set to phantom, and we've had no problems.

We HAVE seen the "can't rez object here" issue, and the "ALT+Zoom throws your camera into the sky" issue. The latter can usually be cured by flipping the megaprim to show its other face.

I did have to delete a couple of megaprims that I was using as a cliff face. It proved impossible to walk onto them from the side, although you could fly up, land on top of them, and walk normally. I don't know why those two misbehaved.

The only megaprim I've used was a 40x20 flat board that replaced 8 10x10s as the floor for my sky platform. The problem was that I couldn't always rez things on it. Since the main purpose of my sky platform is as somewhere to make things, the megaprim was scrapped and its now 8 regular squares again.

Put the megaprim back. Rez a flat tabletop, as big as you need (up to 10x10 of course) and put it on top.

Presto. You solved the rezzing problem and saved six prims.

I've read about megaprims here and several other places. One thing I have never figured out...where can one get megaprims?

You can get a very nice collection of them for free on SL Exchange. http://slexchange.com/modules.php?name=Marketplace&file=item&ItemID=291482

I use 2 20x20x05s for a floor (have the cant rez issue once in a while but not that bad I just try a diffrent spot ) on the Ground physical and I have (4)20x20x05s as grass at 350' for a platform for the house physical

I also did some 40x40x40? cubes as water they are now physical so that you can ice skate on them... one of these crosses a couple meters under ground into Linden land and 1 meter into a neighbors land (underground) still no issues thats it on my land I am sure there are more in the sim though.

you should see one as a sculpti apple LOL

I don't believe that you need to have the objects set to physical to walk or skate on them. Just don't set them to Phantom.

Yes, please no physical megaprims.

I've given up using them at all really, except as bases for things.

I just bought a 2048, and a neighboring club has a construct built on 100 mtr. square megas that intrude over all of the neighboring parcels. Much bizarre stuff as a result. I have ar'd the big prim over my parcel, and hopefully LL will remove it.

People that use these things often don't even check to see if they are contained within their own parcel boundries.

On a lighter note, the offending parcel does not have on no build or auto return, and I found someone squatting in a little sky box hiding under the big platform

Takes all kinds.

I've discovered that cut mega-prims do not always behave as if they've been cut...

The "removed section" still exists for collision purposes, and that may sometimes spill over into neighboring parcels if you're not cognizent of where the bounding box is for your mega-prim.
(neighbors will have a huge, invisible box blocking them)

So, be considerate of your neighbors if you're using mega-prims at ground level, or close to their builds.

Of course, this is all moot if the mega-prim is set to Phantom.

(I agree the 20x20x0.5m are great for flooring in a skybox...just lay a regular prim rug on them for rezzing things upon)