Prim Seams

While trying to build my house I am haveing a problem getting the seams to compleatly vanish. I can get it close but it looks like its 1 pixel off or something. Haveing a dark texture on a wall and a light texture on a floor when i go outside there is the smallest line of the floor texture showing . What am I doing wrong?

Have you built by numbers? I mean ar ethe prims EXACTLY aligned?

Codi is right, the only way to ensure that your corners and edges dont have spaces is to build by numbers.

Also, make sure the inner sides are the same texture as the outer wall. If you dont texture the whole prim and just apply a texture to the outside, the bare prim is more likely to show the tiny line your describing.

There are so many things that can affect prim alignment and seam opacity. One of the most common issues is that the two adjoining joints/sides are not textured or colored to match the exterior views.

Here are some tips that help me. Even with these, I still have a few joints that just won't disappear, so it's apparently not a perfect science.

1. For adjoining prims that are rectangular in shape, always texture or color the joints of both prims to match the sides the exposed sides of the prims.



2. Whenever possible, use round numbers for the prim dimensions (no decimals). That makes subsequent prim placement much easier.

3. If creating something like a wall, copy the first section by shift-dragging the object in the direction where the next section will reside. Now, select the original source prim and copy the object's X or Y value (depending on the direction you are going). Now, add the width of the second prim to the position of the first. Manually input that value into the second prim's X or Y location field.

4. Starting with a "blue print" on graph paper, where each square = 1 m2, can really streamline the actual build process.

Hope that helps and good luck!

Working by numbers only comes out perfect if you work ONLY by numbers. Moving a prim at all by dragging it can cause it to get out of place in the .0001 area, and this can cause tiny little seams along things.

So if you want to work by numbers and come out perfect dont' drag, only input numbers. If you do drag an object, you can get it recentered by taking note of the exact position you want it to be in, then moving it to the side a bit, then inputing the exact position you want.

Also rotations can get things misaligned. If you rotate by hand you'll notice 0 degree can turn into 359.98. this doesn't seem like a big deal, but it tends to build up untill it is an issue. For instance if you rotate something to 359.98 on X axis, and then move it along the Z axis, it's going to start moving off to the side a bit. Also that little bit of rotation can cause just enough tilt to make a seam.

You can usually fix these offsets by inputing the correct numbers for the rotations. so instead of 359.98 input 360 or 0. for 269.98 put in 270.

If you still have seams you might try zooming in as far as you can and moving the object by hand till it's right. The further you zoom, the more precise your drag will be. This is more useful on attachments and things, not so much on houses, buildings, etc.


This stuff can get really frustrating, and it wasn't always in SL, so for old builders it can be even worse. You used to be able to rely on the numbers alot more than you can now. I used to swear by the numbers, but over the last few months i've been building more and more by eye. For tiny stuff...this is great news. for houses and tthings....not so good.

Even working by the numbers (or with snap to grid) is often not sufficient. As a simple example, take two largish prims (10m x 10m x 0.5m) and make them touch each other with mathematical precision.

Given the way the lighting rendering works, if the two prims have a luminance (brightness) higher than about 0.2, there will be a visible seam. Why? My best guess is that lighting is calculated for a given face from the root of the prim. That is, the reflection from prim A can be different than the reflection from prim B because the incident light on the centers of the prims varies by 10m. I think this applies to ambient light as well as local lighting.

The workaround to this is to use either low reflectance textures so that the differences will be not so apparent or to use complicated textures such that the seam is "lost" in the texture.

I thought I was doing something wrong when I first noticed this, too.

On the first point, provided that you don't drag the prim after inputting the numeric location values, there won't be any problems.

On the second point, rotation misalignment is related to a long-standing SL bug. I have had this occur even when setting the numerical rotation value.

If you want to build a prim touching, but not penetrating another prim, try making the prim first, off to the side. Then, while in edit, choose "create", and make sure you have the "copy selection" option checked. This will rez a copy of the object that you have selected, where you point to it. Aim your cursor on the face of whatever you want it to be touching, and click. You will rezz a copy of your floor (for example), touching up against, but not penetrating your wall.If the position isn't exact, you can move it in either of the other two directions, but make sure to keep the same position relative to the object that you want it to touch. You can also do this same thing for building walls. "Copy selection", and click on the edge of a wall....bam, you've added to it's length.

I've found the best way to avoid as many seams as poss when making big things i.e. buildings, is to use a snapping grid set to 0.1 and try and keep dimensions as multiples of 0.2 on as many things as you can. Also don't rotate cubes at all if you can avoid it as small errors seem to creep in, its better to keep the rotations to zero and change the size of the object to fit. When you can't do this its better to try and line things up by changing the numbers than using the mouse but still really hard to get rid of sparkly edges altogether. Everything always seems to move off the grid by .004 as well which is a total mystery to me.

I forgot to mention that even when everything in the construction is perfectly aligned it may look fine from most angles and zooms, but you will be able to some point of view where the seams flicker. I believe that this is caused by either rounding errors from SL to your local renderer or by rounding errors in the renderer itself.

I've even seen Photoshop behave like this when scaling large composite 2D images for display; from that I conjecture that it is really hard if not impossible to get "right" for both Adobe and LL.

I just wanted to thank everybody for this thread.

I'm still in the (very!) early stages of learning how to build, and I would have gone crazy for quite a while before I would have guessed that manually editing objects would mess them up in intervals smaller than 0.01 m.

When i build i tend to use snap/grid at 0.125 (odd i know habit) and when i make a new prim i *shake* it back into grid, since it can be quite odd xyz wise.

I use this oddball 0.125 cause im very bad at math and this way it force me to do it

I been building for many months now. I find using Snap to grid works, usually on items that are 10 x 10. But there are ways to work around this in the game. Mostly building take trial and error. U'll get it. HAVE FUN BUILDING