Is It Something I'm Doing Wrong?

I don't know if this phenomenon is to do with my own idiocy/inexperience or if it's just something that everyone has to live with, but my problem is demonstrated in this picture...



The prims in that shot are aligned so that they are precisely on top of one another yet are not overlapping. I've tried moving them back and forth by tiny amounts, but it seems to make no difference. I still get that little line of white dots (stationary when the camera is still, but seeming to flicker when I move).

What is it and how can I prevent it?

this too happened to me, resolved by thinning on of the stacked prims by .oo1 in width or length matching the stacked prims position coordinates. Made no sense that prims of the same size would not align?

It's artifacts caused by Antialiasing done on your video card. It's very common and very tricky to deal with. The surface facing "up" is rendered a lighghter color than those on the side, and as you see the video card sometimes lighens the pixel at the joint. The only real way to deal with this is to color the hidden faces a darker color.

Usually I've found, its caused by clashing textures or colors or lighting on prims.... gets annoying, but can be fixed almost every time

Okiphia, have you...multiplied?



I sometimes get this when prims decide to move a little on their own, even THOUGH I locked them.

More accurately, it's just the opposite. It's caused by a LACK OF antialiasing, not by antialiasing itself. Turning on AA in the video card settings will put a stop to the problem. Of course, other people who don't have AA turned on will still see it, but all those who are using AA won't. Whenever you install a 3D application on your computer, you should always go into your video card profile settings, and assign a profile that includes whatever graphical features the program doesn't have built in. In SL's case, that means turning on anti-aliasing in the profile.

What's happening in the picture is pretty easy to see. Because there is no antialiasing, all the edges of every object are being drawn with jagged lines. Those light colored dots are present in the gaps between the jags where two adjacent surfaces meet. You're seeing through the empty space between the jags to view the inner surfaces, and since those inner surfaces are perpendicular to the outer ones, they've got a different amount of light on them.

If you turn on antialiasing, all those jags will get smoothed out. Without the jags, there can be no empty space between the adjacent objects. Without the empty space, the light dots will go away.


So how do you turn on anti-aliasing for SL? Read on.


For nVidia Video Cards

If your card was made within the last couple of years, you should have a program called nVidia Control Panel already on your system. If you don't have this program, go to the downloads section of nVidia.com, and grab the right version for your particular video card. It should come with the latest set of drivers for your card, which you should install anyway. Once you've got it installed, simply fire it up, and do the following:

1. Go to the Manage 3D Settings section, and then click on the Program Settings tab.

2. Click the Add button, and navigate to secondlife.exe (or OnRez.exe, or whatever the executable is for your particular SL viewer), and click OK. Your viewer program will now be added to the list of 3D applications that have a video profile on your computer.

3. Click once on the name of the viewer program, and you'll see all its various settings listed below, in a field called "Specify the settings for Second Life" (or for OnRez, etc.).

4. Where it says "Antialising - Mode" set it to "Override any application setting". This tells your video card to forget about whatever SL tells it about antialiasing (which happens to be nothing), and instead to do what you tell it.

5. Where it says "Antialiasing - Setting" assign as much AA as your system can handle. It may take a little experimentation to determine the best balance of appearance vs. performance concerns (the more AA you use, the better it will look, but the slower SL will run). You'll find though that even a slight amount makes a huge difference.

Note, you should make these kinds of changes while SL is not running. Don't try to do it while it is running, or it might crash. You'll see the changes take effect the next time you start SL.

By the way, if you can't find a version of nVidia Control Panel that's right for your card, there is a third party alternative called nHancer that does the same thing. You can get it free at nhancer.com. It does a great job not only of assigning profiles, but also of telling you what each and every setting does along the way. It's a great little utility.


For ATI Video Cards

If you have an ATI video card, you should have a program called Catalyst Control Center already on your computer. If you don't have this program, go to the downloads section of ATI's website, and grab whatever version is right for your specific card. It should come with the latest set of drivers for your card, which you should install anyway.

The instructions for using CCC are very similar to the ones posted above for the nVidia Control Panel. The names of tabs and sections might vary slightly, but it's close enough that you should be able to figure it out.

Again, don't attempt to make changes while SL is running, or it might crash. Assign the settings while SL is off, and then you'll see the changes take effect the next time you start the viewer.


For Other Video Cards

If you've got something other than an nVidia or ATI video card, embedded graphics, for example, you may be out of luck on this. That kind of hardware isn't supported for SL anyway, so you shouldn't even be using it in the first place. Consider yourself lucky if it works at all, and call it a day.

That said, there may be some options for assigning profiles through whatever driver control interface came with the hardware. Consult any help documentation you may have for possible instructions.


Summary

I hope this has been helpful. For anyone doing anything with graphics, from simply playing video games, to doing high end 3D modeling and animation, and anything in between, knowing your way around your video card is almost as important as knowing how to type. Sure you can get away without it for a while, just as you can get away with, say, driving a car without knowing how to put gas in it, but sooner or later you'll run into problems if you don't take a minute to learn. Hardware devices come with driver control programs for good reason. Don't just install them and forget about them. Use them.

well just one problem. I have Antialiasing on, and I still see it.

I stand by my advice, color the face darker, and you won't see it as much.

You'll still see it in places, sure, for a multitude of reasons. But from the picture in the original post, it's pretty easy to see that the author has no AA turned on whatsoever, and it's also easy to trace the shape of the jagged line across the top of the lower prim. The dots appear exactly inline with the jags, suggesting that the two prims are aligned well enough mathematically that AA would make the problem go away.

For prims that are not so well aligned, you'll have some light bleed no matter what you do. I didn't mean to imply that darkening the inner surfaces was a bad move. I just thought it important that people understand what they're looking at. There's no AA going on in that picture.

If, by chance, you have AA turned on, and you're still seeing the dots, even with prims that are perfectly flush, then I'd say maybe your video card isn't doing as good a job as it should with the AA smoothing. And since the reality is that people have all kinds of hardware, some of which works well for stuff like this and some of which doesn't, and most aren't going to read stuff like this to learn how to set it properly anyway, you're right that it's a good idea to take steps in your building process to cater to the masses as much as possible.

lol...Okiphia Anatine was my very first account that was never used. When I found out the 'inventory host' problems didn't affect older accounts, i logged onto her.. she was still at the newly born spot on orientation lol.... used her to test my mountain sculpties..

Upgraded to premium and forgot i was using that account when I came on the forums

Thank you, everyone... Especially Chosen Few for all the antialiasing info. I've turned it on and, lo and behold, I've seen a vast improvement.

Also, Darien Caldwell, thanks to you, I've finally realised that I can have multiple textures on different surfaces of the same prim! Getting wallpaper on the interior walls of my builds has suddenly become a great deal less complicated!