SBH Length Interpolation Discussion. Need some advice please.

Dark45

I've been working in both Zbrush and SBH for hair recently. I'd love to try blender too but I seem to be too stupid to work diffeomorphic properly. I have a test scene that someone else made that works so perfectly but none of my scenes will import properly. IDK, just another frustrating thing I'm dealing with and not the topic of the discussion, sorry just had to rant for a second.

OK SBH, I gave up on this for anything other than fur, male hair, eye brows, etc. because long hair seemed too damn impossible.

Well, I'm giving it another go and you know what, some of my results haven't been terrible except for the interpolation algerithm doesn't want me to style hair I guess. The interpolation of spaces between hairs is decently aggressive but I have tamed that to a point that I'm somewhat ok with.

The length though, I have been fuming for about 6 hours now trying to make this hairstyle. As I style, the interpolated hairs keep getting longer and longer, well past the guide hair length. Issue with this is any hair that is longer than the guide hair will not follow the guide line and is stricken with rigor mortis.

I've messed with everything SBH offers to try and resolve this. So, I am giving it a long shot and posting this to see if anyone out there maybe willing to help easy the suffering a little. If you are able to help, a thousand thank yous and a lovely snack basket will be sent to your place of dwelling.

Have a blessed day everyone!

lilweep

Interpolation doesnt just affect style and position, it affects length too.  Check the style curves near the root of those hairs which are pointing outwards. One of the style curves near the root may be pointed in a different direction and it may be much longer than the ones pointing outwards, so the long one is interpolated with the short ones and you get medium interpolated lengths pointing outwards.

Also take note of your autoparting settings (found under the Style tab) - if you go to any value below 180 (which is the default) you can get weird artefacts like the pointed interpolated hairs sometimes.

A general solution which basically works every time is when you need to create a part (or if you need hair to change direction drastically) is to just split a single hair patch into two different hair patches.  To do this, go to Edit and then duplicate oject, this will duplicate the SBH and you can split the hair in the SBH Paint tab (by painting out the parts that will now be in separate patch)

Splitting means you never have to worry about interpolation from other areas of the scalp. The drawback of course is you cannot visualise the other separate hair patches while in SBH Editor, so positioning the separate hair patches can be very iterative process where you have to go out of SBH edit mode to check what it looks like in viewport, then back into SBH Edit mode.

Dark45

lilweep said:

A general solution which basically works every time is when you need to create a part (or if you need hair to change direction drastically) is to just split a single hair patch into two different hair patches.  To do this, go to Edit and then duplicate oject, this will duplicate the SBH and you can split the hair in the SBH Paint tab (by painting out the parts that will now be in separate patch)

Splitting means you never have to worry about interpolation from other areas of the scalp. The drawback of course is you cannot visualise the other separate hair patches while in SBH Editor, so positioning the separate hair patches can be very iterative process where you have to go out of SBH edit mode to check what it looks like in viewport, then back into SBH Edit mode.

This is what I was just thinking about a couple of hours ago while I was doing stuff around the house. This seems like the best solution. The longest hairs are the ones closest to the side bangs which need to be longer for the hair style. These are the most problematic hairs. Most of the shorter root guides had been corrected (there are still a couple in the image) but those couple weren't much of an issue with interfering with the other hairs when I moved adjusted them.

My plan once I get back to it is to just build it in the 5 different layers that I had already masked in the SBH editor. Not sure how to combine them once done but I could always send the layers over to Zbrush and merge the layers if there isn't a way to do that in Daz. Or just leave them as 5 different parts because I don't plan to use the hair on any other model, not sure but this will hopefully resolve the problem.

Side note, Diffeomorphic works now, I should have thought about the fact that pretty much anything taken from Daz has to be set to base resolution. All of my assets were on high resolution... such a silly thing to overlook.

Thank you for the reply, I do really appricaite it. It helps me rationalize a workflow I was contenplating.

Would you like that snack basket? I'll put a big bow on it.

Truely though, thank you.

UncannyValet

My two cents: it's not as though there is a limit to how many SBH you can have for a given hair style/set.  You will likely end up with at least one additional SBH to add a layer of flyaways or "vellus" with the main hairstyle SBH, plus a few different SBH where the hairstyle direction changed - which caused autoparting to fail as mentioned by the post above.

There is a method to save a whole bunch of different SBH as a single wearable preset:  Assuming the SBH are fitted to a haircap, put all the SBH hair items into a group along with the fitted haircap/scalp, then you can save the whole group as one wearable preset, so can load it on other characters should you so choose.

I think the problem with bringing any SBH out of Daz Studio is you probably have to convert it to geometry first, as there doesnt seem to be any way to convert SBH to blender particle system etc.  Another thing to consider is that within Daz Studio with native SBH you have option to use NVIDIA iray curves to render (if you set the SBH render tesselation sides = 1 in the parameters tab), which renders very fast and will look better than tesselated geometry as it will be a smooth curve.  And as far as i know, I dont think there is a way to utilise the NVIDIA iray fibres/curves for anything imported - so the SBH have to be made in daz itself.

 

Dark45

Stupido3D said:

My two cents: it's not as though there is a limit to how many SBH you can have for a given hair style/set.  You will likely end up with at least one additional SBH to add a layer of flyaways or "vellus" with the main hairstyle SBH, plus a few different SBH where the hairstyle direction changed - which caused autoparting to fail as mentioned by the post above.

There is a method to save a whole bunch of different SBH as a single wearable preset:  Assuming the SBH are fitted to a haircap, put all the SBH hair items into a group along with the fitted haircap/scalp, then you can save the whole group as one wearable preset, so can load it on other characters should you so choose.

I think the problem with bringing any SBH out of Daz Studio is you probably have to convert it to geometry first, as there doesnt seem to be any way to convert SBH to blender particle system etc.  Another thing to consider is that within Daz Studio with native SBH you have option to use NVIDIA iray curves to render (if you set the SBH render tesselation sides = 1 in the parameters tab), which renders very fast and will look better than tesselated geometry as it will be a smooth curve.  And as far as i know, I dont think there is a way to utilise the NVIDIA iray fibres/curves for anything imported - so the SBH have to be made in daz itself.

 

Thank you for the details. The hair cap is a good idea and I couldn't sleep so I went ahead and put something together using some of your guy's thoughts. I still need to add another layer to it at least and the styling isn't done yet, niether is the "dying" which consist of 3 different colors lol, but it's what they want. I'll finish it up after some sleep lol.