Strand-based hair part: do I need a hair cap?

Selek

I'm back in Daz after a hiatus, and I'm having fun making strand-based hair. But my female characters tend to end up with a sharp part that shows too much of the line of their scalp. This does sometimes happen in real life too, but I'd like to eliminate it or at least soften it. Do I need a hair cap of some sort? If so, do I make it myself (maybe using the strand-based hair editor itself), or can I find one somewhere? Or is there a way to prevent showing the scalp in the SBH editor itself? I'm using Genesis 9. Thanks!

Gordig

It's advisable to use a hair cap, but not strictly necessary. If you have a dForce hair, especially one by AprilYSH, you can use that haircap and apply a texture for the hair color you're using.

crosswind

Better show us a screenshot... but as a straight-forward suggest - :

- You better make a hair cap. You may refer to some SBH hair products. It's not difficult to make a scalp as it's just a geometry fitting on the head top with a Cutout Opacity map. Use a modeling software to make one, or adopt a scalp from a product and modify it to have a 'proper edge' aliging with your SBH. Import to DS and conform it to the figure with Transfer Utility. Finally make a proper Cutout Opacity map (or modify one) and asign to the scalp.

- There's no way to make a hair cap with SBH editor but you can use it to make a 'separate layer of hair' as the hair cap, with proper 'gradient length' and 'density', etc. That'll take some time... but the cons is : the more SBH layers you have in the veiwport, the more resource it'll consume and make your Viewport laggy when Preview PR Hairs...

WendyLuvsCatz

another option is a LIE preset

the advantage is one doesn't get overlapping polygons but it needs to use the figure's UV mapping

UncannyValet

You should be able to make hair appear dense enough in the parted area that you do not need to fake coverage with a texture on a haircap or the base figure.  With that said, I suppose the density you can achieve will depend on your available resources, such as VRAM.  

It is hard to gauge what you may need to do without a screenshot. 

There is a section on "Parting the hair" in this post I made which may be useful. It also covers other concepts of the SBH Editor. 

Selek

Thanks  for your replies. I'm a bit embarrassed to attach a screenshot, as I'm still learning how to make this hair, but this example shows a pretty sharp part. My aim isn't so much to fix this particular model as to learn a workflow that will work for future projects. Edit: I tried "attaching a file," but apparently I need an outside URL to upload an image? Here it is:

https://imgur.com/wM7SiFD

I'm working with Genesis 9 products -- just starting to build a collection, really. In my past experiments with Daz, I used the Genesis 8 and 8.1 base figure and noodled around making morphs and Fibermesh hair in ZBrush. So I don't really have much of a library yet. I just bought my first G9 figure -- Marcelina, in this image.

UncannyValet said:

You should be able to make hair appear dense enough in the parted area that you do not need to fake coverage with a texture on a haircap or the base figure.  With that said, I suppose the density you can achieve will depend on your available resources, such as VRAM.  

VRAM shouldn't be a roadblock: I have a new PC, with a GTX4090, 96GB RAM. If I can achieve good results without a hair cap, that would certainly be simpler. I'm already a bit overwhelmed, so I'm willing to buy a suitable dForce hair if that's the quickest way to get me a hair cap (and I'm sure I will be buying DForce hair anyway). But will I be able to retexture a haircap that comes with a vendor's hair? Won't they limit how much I can mod it? If it's dForce hair from a G9-based figure, will it fit on any G9-based figure?

@UncannyValet Your post is very helpful -- one of the best guides I've seen to SBH. I learned a fair bit from it. E.g., I did not understand the option to set sides to 1.  But I was puzzled by your comment about never parenting SBH to a figure, lest its shape change. How can one not parent it? If I save it as a wearalbe, won't I be double-clicking the hair to add it to a figure in the future?  Maybe I avoid this issue by saving it as a scene or scene subset and merging it?

UncannyValet

Selek said:

 I was puzzled by your comment about never parenting SBH to a figure, lest its shape change. How can one not parent it? If I save it as a wearalbe, won't I be double-clicking the hair to add it to a figure in the future?  Maybe I avoid this issue by saving it as a scene or scene subset and merging it?

Currently, parenting an SBH to a figure means that when the figure is translated or posed, translations are inherited by the SBH twice. There is a toggle in the parameters for 'apply transforms' but toggling it to either ON or OFF does not affect the behaviour i described (which may or may not be a bug).

In any case, you will have to keep the SBH unparented. That is not to say it won't be Fitted. If saving it as a wearable preset, it should be saved as unparented, so when clicking the wearable preset it loads unparented.

Selek

Edit: Thanks for the explanation about parenting. OK, that sounds fair. Would you recommend I try a hair cap, or just keep practicing so that I can figure out how to part without showing so much scalp?

Here's a better angle. I figured out which Imgur code to use with the image-upload function here.

felis

UncannyValet

I would just duplicate the SBH twice (once for left and once for right) and then use these duplicates to add more hair specifically into the part area. In other words, on the duplicated SBH, paint out the rest of the hair mask as black except for the part region as white, left and right side respecitively. And change the style guides and distribution seed and other values as required to control the hair in the part area.

I don't think a haircap texture or LIE texture is necessarily required here to solve that issue, but of course is an option.

Selek

UncannyValet said:

I would just duplicate the SBH twice (once for left and once for right) and then use these duplicates to add more hair specifically into the part area. 

Thanks for this advice. I'm trying it. I chose edit/object/duplicate twice. That gives me 3 SBHs in my scene menu, yes? Is the idea that I eventually will "wear" all 3, with the two new ones having little mini Mohawks to fill the gap? If so, why do I need two duplicates? Doesn't one suffice?

Also, I'm wondering if the culprit here is the auto-parting. I've tried changing the auto-part value on my mohawks, but I still see a part. I'm able to conceal it by curling the hair over it, but that looks funny. On top of all that, the mohawks seem to require a higher density to hide the scalp. 

Edit: I'm having better luck just re-editing the original SBH and playing with the auto-part option -- and dragging hair ends around to cover the part, like a little combover, lol. I'm sure this is not optimal, but at least I'm learning how things work. I really wish I could get "curve selection sets" to work, so that I could work on different areas at a time, but I only made such a set once or twice, and then I couldn't figure out how to select and deselect it. The documentation is sparse, to say the least.

Anyway, here's my latest effort. I'm saving as I go, so I'll keep experimenting with this base.

 

UncannyValet

Selek said:

UncannyValet said:

I would just duplicate the SBH twice (once for left and once for right) and then use these duplicates to add more hair specifically into the part area. 

Thanks for this advice. I'm trying it. I chose edit/object/duplicate twice. That gives me 3 SBHs in my scene menu, yes? Is the idea that I eventually will "wear" all 3, with the two new ones having little mini Mohawks to fill the gap? If so, why do I need two duplicates? Doesn't one suffice?

If you can get autoparting to work, then only one additional duplicate would suffice.

Because autoparting is problematic, i suggested that you would likely need two, one for each side of the part. With that approach, you can change the style curves so they only go in one direction instead of both directions. In that way, you dont need to rely on autoparting and can have more control over the exact position of the part by painting in where it starts on each side.

Also, I'm wondering if the culprit here is the auto-parting. I've tried changing the auto-part value on my mohawks, but I still see a part. I'm able to conceal it by curling the hair over it, but that looks funny.

Some people subscribe to autoparting and single guide settings. I on the other hand dont use it because it introduces additional constraints (e.g., interferes with clumping, highly dependent on vertex count in the area of the part, can introduce glitching etc).  It is also hard to control where the part begins.

On top of all that, the mohawks seem to require a higher density to hide the scalp. 

It is expected that such areas of hair require higher density.  

I really wish I could get "curve selection sets" to work, so that I could work on different areas at a time, but I only made such a set once or twice, and then I couldn't figure out how to select and deselect it. The documentation is sparse, to say the least.

That aspect of the SBH Editor should be fairly intuitive.   When using a selection tool you can highlight hair and then create a selection set from that selection by clicking 'New'. Then to select or deselect an existing selection set you can click the add/subtract symbols or buttons.

 

Selek

UncannyValet said:

That aspect of the SBH Editor should be fairly intuitive.   When using a selection tool you can highlight hair and then create a selection set from that selection by clicking 'New'. Then to select or deselect an existing selection set you can click the add/subtract symbols or buttons.

Enlightenment dawns! You've been so wonderfully helpful; I really appreciate your volunteering your time to help me. I wasn't noticing the "New," and when I did stumble upon it, I didn't understand what minus and plus meant. They simply add or subtract to the set(s) you have selected. Oh my. This will make things much easier. I think you're probably right that using these tools is easier than the auto-part. It looks like I turn auto-part off my turning its threshhold either very low or very high -- I'm not sure which.

I don't understand the 'single guide' controls at all. I play with them, and things move about semi-randomly, it seems. Again, I'm inclined just to ignore them, as you're suggesting.

Finally, do you have a suggestion on a vertex count to aim for? My first effort was 5 million vertices, which is a bit much, even with this fast new system. My next was 1 million, which seems quicker. Choosing 1 side in the tesselation parameter certainly helps -- another of your useful suggestions.

Thanks again for your help. I've been reading and re-reading your guide, and playing with this all afternoon, and I think I have a better feel for it. I've used ZBrush's Fibermesh too, but I actually prefer the results of Daz's SBH system for longer hair. (For shorter hair, Fibermesh works well.) I haven't tried other hair solutions yet. For dForce hair, I guess I have to buy from the Daz store, but I'm trying to limit my purchases lest I go bankrupt, and I can make at least passable hair to get me by while I learn other things. My larger project is to think about what I can make myself using ZBrush/Blender/Daz-SBH with reasonable efficiency, and what I should buy from the Daz store.

Selek

Just a quick update to show my progress, modest though it may be. I did another couple strand-base hairs, and I think they're looking better. A bit of camera F-stop manipulation helps, too.  :)

UncannyValet

Selek said:

UncannyValet said:

That aspect of the SBH Editor should be fairly intuitive.   When using a selection tool you can highlight hair and then create a selection set from that selection by clicking 'New'. Then to select or deselect an existing selection set you can click the add/subtract symbols or buttons.

 

Finally, do you have a suggestion on a vertex count to aim for? My first effort was 5 million vertices, which is a bit much, even with this fast new system. My next was 1 million, which seems quicker. Choosing 1 side in the tesselation parameter certainly helps -- another of your useful suggestions.

What i say is not gospel but I would suggest making the hair look the way you want and then after that look at optimising it as necessary (e.g., via hair density, segment length, and interpolation segment length). I guess the final vert count depends on what you can manage in a render.

Chevybabe25's feisty feather bun is allegedly 1.5 million verts, which could serve as a normal value for hair with Line Tesselation Sides of 1.  There are definitely hair with much higher vert counts on store. 

Selek

UncannyValet said: In any case, you will have to keep the SBH unparented. That is not to say it won't be Fitted. If saving it as a wearable preset, it should be saved as unparented, so when clicking the wearable preset it loads unparented.

Hmm, how do I save it as a wearable preset without parenting it to the figure? I only seem able to save the hair with the figure if the former is parented to the latter. (The hair is fitted to the figure, but not parented to it.)  If I unparent and try to save the hair alone, I get an error message. If I unparent and try to save the figure, I can do so, but I don't get the option to include the hair as a wearable item, even though the hair is fitted to the figure. 

Incidentally, Daz also let me save the asset as a prop, but I had the double-translation bug you mentioned. I've spent a frustrating afternoon trying to translate my crazy hair to my bald lady in a new scene. Loading a scene subset does work, but that means the hair is always tied to this one figure, it seems?

UncannyValet

I recently ammended the section on saving SBH (see the final section of this guide)

Saving Wearable Preset without Haircap: If you have not created the SBH on a separate haircap/scalp, then you can still save as a one-click Wearable preset, but it involves a workaround:

1. Create a new Group using the default options, and rename the Group to a suitable name for the hairstyle (e.g., "Long Curly Hair")
2. Place the SBH into the Group (in other words, ensure unparented from the figure and instead have it parented to the Group)
3. Place any fitted item into the Group (a fitted item could be a random clothing item, a random hair cap, anatomy, anything fitted to your Genesis figure. it does not matter so long as it allows you the option to save a Wearable preset in step 5)
4. Select the figure that the fitted item and SBH are fitted to (e.g., the Genesis figure) in the scene tab
5. File>Save as...> Wearable Preset
6. In the popup dialog, select the whole Group to save as your Preset and also deselect the fitted item from step 3.

edit: Updated link 

Selek

UncannyValet said:

I recently ammended the section on saving SBH (see the final section of this guide)from step 3.

Thank you so much for this. I will give it a try tomorrow. As you say in your comment to your guide, SBH may be our best option for hair right now. I'm getting better at it, and I like my imperfect SBH more than the hair I've bought from the Daz store so far. And mine has no more polygons than the stuff I've bought.

Incidentally, the link I've quoted here doesn't seem to work, but I found your guide by clicking on the link you provided earlier in this thread. I do see the amended section on saving SBH. Your guide is still the best thing I've read on SBH -- it actually explains systems in detail. Thanks!