Alpha Textures - Sim Performance

I've read that alpha textures can adversely affect sim performance. And I also saw a suggestion posted about using completely transparent alpha's on joints in builds, to hide seams. Might it be better to use a blank texture and color match or use black on the non-visible sides to acheive similar results?

I'm also curious to know if non-visible textures are rendered or cached by the client....



~L~

A texture is a texture is a texture. Sim performance isn't going to be affected in any way whatsoever (well... higher resolution textures are more of a hit... but nothing to do with alpha).

- Ace

Uhhhrrrmm...

The only way it'd be a strain on the sim is if a 32 bit texture is larger than a 24 bit one. Which it probably is. But that's not much of a difference.

The strain is on the user's computer, if it's anywhere.

Thanks guys,

That makes sense. I can put my texture dilemma to rest...

~L~

Alpha textures do not significantly impact the simulator, but they do cost some extra rendering time on the client. This is because, in order for them to be transparent, they are rendered in two passes.
And yes, a texture is a texture. Invisible textures are downloaded and cached.

Yea if you mean SIM in terms of "SL gameplay experience" then yes they will make things very slow and laggy.

Jack: lets not confuse the meaning of sim by suggesting alternate definitions; for it's application to SL.

Textures that are semi trans or alpha will effect client proformance but will have little effect on the sim.

Animated semi trans alpha textures that overlap will give your client a good workout.

A texture is a texture is NOT a texture.

It's my understanding that an alpha texture is thought of as one texture in the database....and (now, this is how Cath Omega explained it to me, please correct me if I'm wrong) the SL system will only store the FIRST instance of any texture in the database; after that, all other copies of the texture are simply references to that first instance, along with the permissions that the current user has to it.

SO, if you have an alpha texture, it matters not only what bit-rate it is, or whether it was uploaded as a .jpg or .tga. It also matters where it originally came from.

Example: If I upload an all-alpha texture, and share it with all the residents in my sim, we are all using the same "texture" as far as the system server is concerned. More bandwidth-friendly.

If 12 residents of a sim are all using alpha textures, and each one is using a texture from a different original source upload, then as far as the server is concerned, there are 12 textures to downstream from that sim, for anyone who cares to wander thru, all of which mean "invisible".

So, by agreeing, as a group, to use the same textures, you can improve your sim's performance. Good luck trying to get everyone in the sim to use the same alpha texture; but for every ONE person who agrees on a common texture or set of textures, you've improved the downstream performance of your sim a little bit more.


PLEASE, any of the more technologically savvy, correct me if I'm wrong on this; this is my understanding of it, though.

it used to be, and I'm no longer sure this is the case, that if you had too many things in a sim set to some alpha value it would cause a wierd looping precache bug.