Textures disappearing ...

[Katherine Heartsong]

Practicing getting my art onto nice birch panel "canvases" in my gallery. I have three decades of design so have no issues creating the art, working in 128px sizing increments (1024x1536, for example), getting good file sizes, etc. I have worked my way in building up to getting great birch texture I can use in my panels, building the panels (flat surface pieces plus 5 support pieces across the back, all linked after I add the art texture to the flat panel), etc. I have even figured out how to select only one face of the flat panel pieces to apply my art to, upload my art, etc. Here's the issue ...

It looks good on the day I create it, but I will often come back to the space and find the panels solid grey, like the art and wood textures didn't "stick".

What am I doing wrong? My newbie question for the day.

Thanks!!!!

PS. The gallery is in a skybox, but the sign on the ground I made has remained fixed (and looking fine) since I made it a week ago.

Edited November 7, 2020 by Katherine Heartsong

[Rolig Loon]

Possibilities:

1. Rendering lag.  That's the most likely problem, although not as likely in a skybox as on the ground, where your viewer has to load a much larger mess of textures within its draw distance.  Still, it's a common problem.  

2. Local Texture.  You may have discovered that you can apply a texture on your hard drive to a surface in world temporarily, using the Local Textures option. That's really handy if you want to try a number of provisional textures and saved the cost of uploading each one to SL.  The downside is that the textures are not really uploaded.  They are only temporarily displayed for you to view until you log out.  If you were testing local textures in the skybox and then uploaded real ones and applied then on the ground level, that would explain it.

 

[Katherine Heartsong]

May have solved it ... my 2m x 3m textures are 1024 x 1536. Max allowed width/height is 1024. I'll fix them.

[Rolig Loon]

56 minutes ago, Katherine Heartsong said:

May have solved it ... my 2m x 3m textures are 1024 x 1536. Max allowed width/height is 1024. I'll fix them.

You should do that anyway, because otherwise the system will automatically resize your textures as you upload them, setting their dimensions to the next lowest power of 2 (in this case, 1024 x 1024).  That means your textures will be slightly squished.  The way to avoid that is to set their dimensions yourself before you upload them, and stick to powers of 2.

Fixing that shouldn't affect the gray problem you are seeing, though, unless something else is going on.

[Katherine Heartsong]

Okay, ty for the help so far and I have headed off and read the SL Knowledge forums about textures sizes. I'm still perplexed though about the whole "powers of two" thing.

IRL, I usually work on panels and canvases that are not square. I can, but for this example let's use some common sizes. I might paint something on a 60x48" surface. 5ft x4ft. So a ratio of 5:4. In other cases I'll work on a surface that's 6ft x 4ft, aka 3:2 ratio. Sometimes a 4ft x 3ft (4:3) and often larger—my stuff goes up to 8ft x 6ft (again, that 4:3 ratio). That's how I work in physical media and tend to do the same with my digital painting as well, since the aspect ratios remain mentally and compositionally familiar to me.

Yet SL, with the powers of two, does not seem to allow for any ratio except 1:1 or 1:2 or 1:4, always powers of two. 256x256 or 256x512 or 256x1024. Except for the square one, none of those ratio makes a decent surface to divide and compose on, I have found IRL. Square 1:1, perhaps, but if I'm offered a panel that's for example 3ft x 6ft (1:2) I find it's too narrow to work on. I need it to be 4x6 or 5x6.

Which brings me back to my digital work. 4:3, for example, in the largest size texture SL accepts, is 1024 x 768. But 768 isn't on that powers of two list and does that mean if I create something 4:3 it'll distort down to 2:1 (1024 x 512)? Is there no way to stretch my texture back up to the 4:3 ratio within the world to mount it on a panel of that size?

Edited November 7, 2020 by Katherine Heartsong

[Rolig Loon]

Regardless of what the pixel dimensions of your image may be, you can stretch the "canvas" (prim face dimensions) and change the aspect ratio of the displayed image on the face as much as you like.  If you are careful about it, you can apply some deliberate distortion to an image before you upload it, for example, and then "undistort" it as you apply it on a prim face.  You do have to be careful, of course, because your stretching in world will affect resolution somewhat.  So, don't plan on stretching a 512 x 512 image to fit on a face with a 5:2 aspect ratio. Still, if you use your head and your artistic eye, you can get away with moderate distortion.  This is where those Local Texture tests can be helpful.

[Katherine Heartsong]

Sounds good. I have reduced my original 1024x1536 down to 638x1024 and will do some tests. Thanks so much. Still trying to solve the other issue though, and will report as I learn more.

Edited November 7, 2020 by Katherine Heartsong

[Wulfie Reanimator]

56 minutes ago, Katherine Heartsong said:

Which brings me back to my digital work. 4:3, for example, in the largest size texture SL accepts, is 1024 x 768. But 768 isn't on that powers of two list and does that mean if I create something 4:3 it'll distort down to 2:1 (1024 x 512)? Is there no way to stretch my texture back up to the 4:3 ratio within the world to mount it on a panel of that size?

If your original work is 4:3, it'll be reduced to 4:2 on upload, but you can still create a 4:3 surface to display it on. This will essentially "stretch it back" into its intended dimensions.

The only thing you lose is quality -- but that will happen even if your original work is exactly 1024x1024 (for example). It's just the nature of SL's texture format.

Edited November 7, 2020 by Wulfie Reanimator

[ChinRey]

2 hours ago, Katherine Heartsong said:

Yet SL, with the powers of two, does not seem to allow for any ratio except 1:1 or 1:2 or 1:4,

It's not SL as such, it's OpenGL and I think it applies to the other graphics APIs too, so there's nothing LL can do to change it.

It's not a big problem though. As Rolig and Wulffie said, just make sure the surface you apply the texture to has the right ratio and the texture will stretch to fit.

 

2 hours ago, Katherine Heartsong said:

Still trying to solve the other issue though, and will report as I learn more.

If the surface turns gray the next time you log on, it means you were using local textures. There is no other possible explanation.

I assume you did upload the textures but did you remember to reapply them afterwards? That's a step that is very easy to forget - I do it myself all the time - but also very easy to fix. If you see a gray surface like that, find the texture you uplaoded in your inventory and add it to the sruface. You only have to do it once and it will stick.

[Wulfie Reanimator]

1 hour ago, ChinRey said:

It's not SL as such, it's OpenGL and I think it applies to the other graphics APIs too, so there's nothing LL can do to change it.

No, OpenGL (and any other well-established graphics API) is able to support any arbitrary size image. It's completely trivial in principle, but there are probably some kind of technical reasons (such as optimizations) for LL to limit texture sizes to a set range.

Edited November 8, 2020 by Wulfie Reanimator

[Katherine Heartsong]

All sorted, thanks for everyone's help.