Prim hair and texturing

Hi
This is my first post to this forum, so please go easy on me!
I've had a stab at creating prim hair, it's still a work in progress but I'm getting there slowly. My problem is hair textures. I'm not a PS whizz, though can do basic stuff or follow step by steps tutorials. My friend is trying to make textures for me but I'm not able to explain to her what it is I want.
I'm pretty sure, through trial and error of the SL inventory hair, that I need a complete square of hair without the wispy ends for most of the prims. I'm finding though that on toruses (tori?), especially when they are spiral types, there seems to be "running" in certain planes of the prim, looks a bit like ants crawling. (I'm sure there's a technical term if someone could enlighten me lol). Also I seem to be having an issue with the textures/prims blinking and going invisible - not always.
Now I'm not sure if my problems are my prims, the textures I'm using or a SL bug. Any help would be very much appreciated.
Thanks in advance.
Louise

Hi Louise,

I'm also learning to make hair and have been experimenting a lot.

It probably is the texture - the "ants" could either be what is in the texture (ie the lines being fuzzy or too small), or the rotation of the texture - on the texture tab there are some settings you can alter to rotate the direction of the texture on the prim.

The flickering is probably due to an alpha channel on the texture - any textures that are designed with the alpha channel for the "fringed" look will flicker when they are on top of each other. I have read here in the forums that it is due to the way that alpha textures are rendered in the 3D program, so the solution is usually to either use a texture without an alpha channel (if you are doing curls or tapering on the prim itself), or if you are, to use some prims on top of the textured 'fringed' ones that do not contain the alpha channel.

I learned a lot just by buying hair others have designed and decontstructing the pieces to see that this is how folks have done it. Good luck!

And yes, you are right, the linden hair textures are really meant for the avatar hair on the appearance option, not for use on prim hair because of the fringing. I believe those do contain an alpha channel which would explain what you described. I use either a 512x512 or 256x256 square texture for my hair. I learned recently that it may be better to always opt for the 256 texture because of the lag that prim-heavy hair can create and the higher resolution probably does not gain you much but may bog you down. I recently created a 132-prim curly head of hair but it literally lags out the area when I wear it, so I need to go back and reapply a resized texture to see how that goes.

Best!
Myst

Myst,
A huge thank you for your replies. We played with the rotation of the texture and have lost the "ants"! I can't tell you how happy we are lol. So back to the designing now, hopefully I can now refine the prims
Thanks again,
Louise

this is helpful to me toos ty guys

Hi!

Mystikal, I hate to break this to you, but changing the texture on 132 twisted torii isn't going to make any difference. The problem isn't the texture; it's the twisted torii.

Every point, or vertex, on an object takes a tiny bit of processing power to render. (Professional 3D game artists go to all sorts of lengths to keep the vertex/poly counts in their models as low as possible because of this.)

The different prims in Second Life have differing numbers of points. For instance, a cube normally has 8 vertices (on one each corner) which make 6 polygons (one for each face.) When the prims are twisted, the number of vertices and polygons increase. The more they are twisted, the more points and polys are necessary to mathmatically describe that shape, and the harder the processor has to work to render it.

I'm not sure how many points an untwisted torus has; but I'm guessing it's dozens, even at the lowest resolution. (The SL engine is smart enough to change the count depending on the distance and size of the prim, which is why cylinders look like hexagons when they are small and far away.) When you start to twist those things, the number skyrockets.

When you move the twisted torii around, which you do if they are attached to you, the problem gets even worse, because each point needs to be constantly recaluculated.

132 twisted torii are always going to bring a sim to its knees. Even if you cover them in plain black, with no texture at all, it's going to lag. You're eating up every processor cycle in the sim to render your hair.

The solution? Don't do this. Please, please, please don't do this. I'd be happier if no one ever used twisted torii in their hair, but I realize that's not going to happen. But please, don't use many. I'm having great success selling hair that's mostly based on texture, with very few (or no) prims used, because people don't really want hair that causes lag.

In other words, what good is the most beautiful, realistic, frizzy hair in all of SL if you can't ever take it out of your inventory?

Louise, the "ants" you refer to are commonly called "pixel crawl," or, more technically, "temporal aliasing" or "raster scan aliasing". They happen, as you guessed, because there is too much contrast in the fine lines of a texture. They are rendered in one position one moment, and a slightly different position the next, which gives the effect that they are crawling. Blurring or decreasing the contrast can both help to minimize the problem.

Mystical was correct about the alpha sorting problems. So yes, you'll have better luck with 24 bit textures if you don't need the whispy ends.

Hope this helps!

Robin,
Thank you for your comprehensive reply.
That was very helpful

Louise

Hmm thanks Robin - that actually saves me a lot of work. I wonder then if making the curly tori shorter/smaller/less twisted would improve the rendering. I have been playing with textures to be able to make cool hair with fewer prims. This forum is great - there is so little help out there for wanna-be hair designers. All the builders I know in SL say "wow, you're starting with hair? that's like the toughest thing to do" .

Hi Louise and Mystical! Glad it helped.

Mystical, shorter and smaller won't help, unless by shorter you mean fewer iterations of the spiral. Less twisted will. But I'm afraid that what you really need is fewer prims. Many, many fewer. Try to keep to less than 15 or 20. The fewer, the less lag your hair will cause.

Using a different prim, or using textures instead of prims, can be very effective. Someone showed me a wig that was mostly a base hair and what looked like a very frizzy ponytail, but was actually just three cubes with a frizzy ponytail painted on them, the way that most in-world flowers are made. From any distance at all, it looked great, and didn't cause any lag. It was her favorite hair, and the one she wore most often, because she could wear it anywhere without any worries.

Remember, all of this is really just illusion; all you need to do is come up with a way to make the illusion look convincing enough to pass at screen resolution. Most people you meet aren't going to be zooming in for closeups of your AV. (At least, I don't think they do. )

So don't be afraid to try something that's never been done before.

If you are having a hard time finding your way around the Base Hair, I do have instructions about how to make it work for you at my Texture Tutorials in Benten. (I'll edit this later to add the co-ordinates. I don't remember them right now.)

Hope this helps!