Problem with stacked Alpha textures

As you can see in the attached picture, stacked alpha textures don't show right in the new viewer.

The alpha (or semi-transparent) texture on the above lying prim (the lemon table glass)does not show under certain angles. The original targa-texture itself has no alpha, but the prim is set to 50 transparency. Underneath (the carpet of leaves) is a prim with an alpha channel in the targa-file. The prim itself is set to zero transparency.

The problem occurs on certain viewing angles. When viewed at a slightly different angle (see pic) the problem is not there. Also: when I place the table on a solid surface, the problem does not occur. So only with stacked alpha prims.

This must be the new viewer. But will it be solved soon or is there another solution? This stacked alpha-problem is really bad for a designer and my customers!

Alpha problems have existed for a long time. The fact that they still exist in the new viewer should answer the question of whether they will be fixed anytime soon

while it's true that this problem has "always" existed in SL.. it seems that the occurrence of this bug has increased in FL (and therefore 1.14).

I too hope they can at least get alpha sorting as good as in 1.13.2... it was almost reliable.

I know alpha problems exist a long time. But the two stacked textures looked fine before this update (under any angle).

I looked at the release notes once more and found this:

** Alpha sorting changes to improve performance

This MUST be the cause. Could the prob temporarily be solved by making the targa-file itself (so the texture itself i mean) semi-transparant?

Hmmm, have tried making the texture itself transparent, but doesn't work. Damnit. Why in gods name did they change this???

I can't log in right now, so I can't tell you if semi transparent TGAs look better or worse in the new client.
Probably best to make a copy and see which one looks better.

You could always throw in a switch so buyers can select which they prefer using llSetPrimitiveParams to change the texture and transparency.

Edit: you did use a shade of grey on the alpha channel for the texture?

Good tip Sys, thanks. But also a grey shade in the alpha channel doesn't help. I tried that, but got exactly the same effect as with setting prim transparency.

I've managed to get in world, and my wings look like garbage. The way the alpha keeps flipping one in front of another is almost nauseating.

What are the chances that Linden will allow the old client to remain on the grid?

There is a workaround for this that I have found useful,
If you have an item you can hollow out use that. lets say you have a sphere, hollow the sphere out cut it and texture the inside transparent, then close it back up and shape your sphere. as long as you have an underlying plate between the 2 transparent items linked, they will not flip flop.

Thanks for that, I'll give it a go next time I'm in world.

You are lucky, my textures are being rotated 90 degrees. Clock pendulums aren't supposed to be lying horizontally!

1.14 is a nightmare! Worst Ever! LL is offering a download of 1.13.2 again. What does that tell you?

Well I tried the transparency with hollow, and it seemed better initially but the flipping problem is still there. It's easily noticed while dancing.

I know, it's ridiculous. Why did LL change something that was good for something that isn't? Never mind, I already know the answer...

I reported a number of nasty alpha flaws in places that worked fine before, especially apparent in builds that use .tga textures with transparent areas for windows, or on fences etc. But nothing seemed to be done =(
I'm all for better performance in preference to new fancy graphics, but if it makes the exisiting graphics look and behave worse then that's not a good thing

I don't agree that 1.14 is the worst update ever, I get a full 10fps faster on my machine by enabling vertex buffers (+5fps) and enabling "run multiple threads" (in debug menu client >> Renddering, +5fps)

The First Look viewer has had alpha problems from day one. It seems to be the result of having the video card take on more of the work of doing the rendering.

They really need to subdivide alpha surfaces to allow the GPU to calculate the layering for different parts of the surface separately.