Skybox Seams

Hey there Blenderheads,

I’m working on a flight sim using the realtime engine. I’ve run into a problem with my skyboxes that I can’t seem to shake. No matter what I do I get seams appearing along the edges of my skybox. It’s not a problem with the graphics - they line up perfectly in Photoshop.

The textures are 512x512, and I’m running with a Geforce4.

Any ideas?



By seams do you mean just black edges on the edges of the box? Also, is the sky texture tileable from top to bottom as well as side to side?



Yes, the seams are on the edges of the cube I’m using for my skybox, except they are kind of gray.

The images don’t tile top and bottom OR left and right. I’m using 6 different images (one for each side of the cube) generated in Bryce. I checked their alignment in Photoshop like I said and they align perfectly.

Here’s a screenshot of the seams…



what i do to get rid of this is on all the textures for the skybox, scale down the uv coords just a bit so all the images are mapped 1-2 pixels inset on all edges of the image

Yes, if you notice, even on just a single plane, the default UV calculation for it seems to be one pixel too much to one side of it, depending on the image you can notice that it loops back around to the other side of the image. Try making the uv one pixel smaller than you think it should be.

Another thing to try would be to adjust the clip sta: of the camera (select camera and go to the edit buttons). Sometimes, putting it up higher can help eliminate some graphical glitches, although it does also limit how close to the camera objects can get before being cut off.

Pulling the UV coordinates in 1 pixel worked the trick - the seams are banished. :smiley:

It’s funny you should mention the ClipSta thing. I had a lot of glitches at first (hills appearing in front of hills they were behind and faces on objects disappearing randomly) that ALL were cleared up just by setting ClipSta to .1

Don’t you love stuff like that? Try and track down a bug for 5 hours and it turns out to be some weird solution that shouldn’t work but does.

Thanks for the tips.


i look forward to seeing your game