Weird transparency questions

How do you know if you got transparency halo?
Friend told me what I am experiencing is transpaency bug if I have several transparent images together they look like either they have partially vanished or the layer to side looks like its merging in weird way to front texture.
Is this a bug or am I doing something wrong.
I am using png files.

it could be a bug, and it has to do with alpha sorting.... there's a jira issue on it, alpha sorting reversed or something....

basically it boils dow to sl not showing alphas in proper order (allowing farther objects to overlap nearer ones


I experience this with my prim hair (which fades to alpha) alot... if I stand in front of a object with partial transparency like a house window, looking at my av with the window behind, my hair looks faded because the window texture is showing on top of my hair...

if that's Not what seems to be happening, then it's something else, and I'm not sure w/o seeing it

You know you have a halo if you see a halo. I don't know how else to explain it other than that. If you can see it, it's there; if you can't, it's not.

I think your real question is what does a halo look like. The answer is it looks like a white outline or a white glow around the opaque parts of the image.


Re-read the FAQ section of the Transparency Guide. What you're experiencing is the alpha sorting glitch. It's common to all OpenGL applications. When two or more surfaces with transparency are placed near each other in close proximity, the renderer has trouble determining which one to draw first.


A couple things here. First, what you're looking at in SL are JPEG2000 files, not PNG, not TGA, nor anything else. Everything in SL is JPEG2000. Your source image on your own computer may well be PNG, but as soon as you hit the Upload button, it gets converted to JPEG2000 for insertion into SL.

Second, the sorting behavior would not change, even if that conversion were not happening. As I think you and I have discussed before, PNG and TGA textures behave identically when applied to 3D geometry.

gee i just wandered onto this thread cuz i thought the transparency thing might be like an invisiblity cloak or something
lol
but wanted to thank you all for explaining in termsi could understand - it was interesting to read about
like finally something like this didn't just go whoosh right over my head

I have used lot of transparent images and I never noticed any problems with transparent images until I started making them this month.
I finally figured out how to do png but regardless of how many times I try to read or do steps I can't make a single transparent tga image. The something I am missing and I am clueless to understand why.

Everything Chosen Few says is true (except when he bashes GIMP . However, to be really precise, you are not even seeing JPEG2000 files. Instead, you are seeing whatever your graphics card extracts from it's memory and displays on your screen.

FD, what tool are you using to make TGA?

Whatever it is, TGA usually has an option to save as 24 bit or 32 bit. If there is transparency, you have to pick 32. If there is no transparency, you can use 24.

Maybe that's your problem, saving as 24 bit...

Or you make the mistake I've made and save as 32 bit when no transparency is needed in the texture. You get needless alpha sorting problems.

Man until Cel told me about save as web I was going over and over steps including saving as 32mb but nothing was working I use older version of photoshop CS version 8.0 and sometimes ps 6. Haven't been using corell i hate gimp.

dunno how it works in other programs, but in PSP you make your image if it was made on a transparent background you choose create mask from image, uses source transparency, then save mask to alpha channel

if you didn't make it from a transparent back ground, you make a new layer, paint of the parts you want to see in white, flood fill the rest black then as above, create mask, use source LUMINANCE, and follow trough...

save file as tga, hit options, choose 32 bit, uncompressed (no point in getting hit on compression twice) and upload... the second method is more prone to halos (off-colored edges)