What is prim drift?

I read someone complain about "prim drift" on another thread. I have an idea what this might mean, but I don't know.

What does it mean?

coco

I think it's when textures don't line up properly and even when you've set them up by numbers you get that overlap textures fighting or rather flickering back and forth.

While it's possible that different people have different definitions, usually what people mean when they talk about "prim drift" is an annoying little bug, which causes prims to move around slightly (or sometimes more than silghtly) for no apparent reason. At times, I've had pieces of linked buildings all of a sudden end up overlapping or seperating from eachother after having previously been perfectly aligned.

The worst case of this I ever had was several months ago when the Sci Fi Museum and the Bird of Prey hovering above it both appeared to have exploded. Bits and pieces of the building and the ship were scattered across half of Indigo. LL was kind enough to roll back sim about 12 hours, which fixed the problem, but man was that a frightening experience.

Generally speaking, building in SL is pretty stable, but every once in a while the system suffers a bout of mathematical vomiting, and it can be pretty frustrating.

Oh sorry, I was thinking of something else.

Ok, that's what I thought. I've learned to let a house "set". That's what I call it. That's where you log off and then go back the next day to see if any of the dang prims have moved out of alignment.

That's why I got excited when I heard the term "prim drift." It meant that no, I wasn't slowly losing my mind, and yes, my conviction that prims sometimes moved of their own accord - AFTER you KNOW you've gotten them perfect - was sound.

coco

i guess the defiant opened fire on it then lol

ps go see the defiant in indigo

Where possible, keep a copy of your stuff in inventory. One day when it blows up, delete it and rez a fresh copy. The great thing about inventory though, is you can rez a project you are working on, and start editing: while working you <Tools | Save object back to inventory> every now and then. It's like hitting File Save in your word processor every five minutes:- better safe than sorry.
also, when you reach major checkpoints in your build process, copy the object in inventory, paste it back in, and rename it with a version number. keep the last couple of version in case you need to roll back.

whew......i thought it was just me that this happened to. i was beginning to think that sl would have minor earthquakes overnight while i was logged off

actually is it possible that some sims are worse for this than others. i have lived in 3 different sims since i started & 2 had no problems whatsoever. the sim i just moved from however was horrible for this

Drift doesn't know...

I've noticed prims in my builds have repositioned themselves from time to time. There are also minor bugs like editing linked objects... you resize a child prim, and it looks fine, but when you next log in, the child has returned to its original size.

The most serious case of prim-drift I've ever seen was when I one day discovered a large chunk of my skybox rotating merrily end-over-end. When I clicked on it to edit, it returned to its previous position and stopped spinning.

Another issue that happens related to prim drift is that despite your best efforts to get it perfectly aligned there's still a crack. In the SL editor the level of accuracy is limited to three digits beyond the decimal place, example (X: 153.456, Y: 45.678, Z: 22.000), but the level of accuracy of the game is five digits beyond the decimal place (X: 153.45661, Y: 45.67829, Z: 22.00000). Because of this sometimes your position, rotation and/or scaling can be just slightly off.

Is there away to over come this accuracy problem... i'm noticing it much more now that i am building walls that have three 10 x 10 x .25 blocks. It's getting aggrivating

ooh they call that prim drift..here i've always called it "!@!$@!! #@!$!$#%^&% !@!!!!"

You can make scripts that can circumvent prim drift.

That, however, takes time, and it's easiest to just reset the positions and/or re-rez the object whenever they get off alignment.

The nastiest form of prim drift, however, is their tendency to move if you rotate them. When figuring out door scripts, I finally realized this and had to do a work-around for it.

little off topic, but one person asked how to compensate for prims next to each other not quite lining up. IF building a wall, alternate the wall thickness by .02 and make sure you texture the ends of the thinker wall portion. There will be a tiny visible difference in the walls. But you can now overlap the prims by .01 on each side without texture flicker. I rarely use this on wall sections, but find it very useful for arched bridges and other situations where the prims must overlap to create the final structure.