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Hair Blunder in Blender

I got this blender model imported in successfully in except for the hair. This Model won’t show his
hair properly up in full in Unreal Engine. The hair was done in Blender Cycles. Anyone
know how I can fix the hair?

https://i.imgbox.com/aNzIVDMJ.png

How was the hair made? It’s hard to tell what exactly I’m looking at with such a low resolution image. Is it geometry for every strand, texture planes, or some physically modeled strands and planes mixed together? If it’s the first one then you absolutely shouldn’t be doing that: it’s insanely high poly and is going to cause all sorts of issues. You also shouldn’t be trying to use the raw output from a Blender particle hair system as this gets converted into thousands of polygon strands and causes the exact same issues. If it’s any of the latter or you’re projecting the output from a particle hair system to hair planes then your problems could be the result of inverted normals, 2-sided geometry that doesn’t have a 2-sided material assigned to it, or both.

Hair was made with Blender’s Particle system, I didn’t make the hair, someone else did. it Looks great in Blender, but comes out a mess in Unreal Engine. I did convert the particle hair into mesh in order to export the model with his hair and Blender gave me this mess. So how do we fix it? Its no good Blender just doing hair particle systems with cycles render if the hair just flops in game engines., The hair has to work also in game engines as well not just for posing art.

You need to make an entirely different setup for hair in order for it to work in UE or any other engine, check out hair tutorials for games involving planes and such and go from there. Hair with individual thin hair strands wont work here at all.

Everything that Blender program touches it just messes up. if its not the rigs, its the hair. Ok so Blender dosen’t do flat hair planes with its in-built hair generation system, which means its useless outside of blender. Well thank goodness my Ship’s Pilot’s hair was done with flat hair planes in Blender, for that imported into Unreal Engine without any trouble but generating hair with Blender’s Particle strands, Nup, and I also don’t like people generating these Shaders nodes inside of blender also for hair because its likely they won’t work outside of blender unless they got a way of baking the shaders onto the mesh. Maybe I could try radial or Screw modifier to the hair and see if that does anything.
Maybe one day they will make a plugin for Blender to Generate flat Hair Planes on your mesh. By taking that particle hair strand junk and decimating it into flat hair planes with a low count.

Tozan, hold your horses :slight_smile: Blender is not to blame here.

Here’s what is happening, any software including Maya and Max has hair system either particle or strand based. But none of them will export the hair as is to UE, because realtime works very differently than offline. Blender is no different.

You will find it hard to find a software in any of those packages that will do flat hairs for you automatically (Actually yes there are a few plugins that help the process, there’s one for Maya ‘GMH’ and there’s Ornatrix for Max which can help) but at the end of the day hair creation for game use in either of those software is going to be hard, manual work. Most of the time the way we do it is manually placing and shaping every single hair strand onto the head and modeling them one at a time. This is how everyone else does it, even the folks at Naughty dog who created Uncharted.

You can have software like Zbrush help with the visualization first and get some references etc… but at the end of it be prepared for some serious labour intensive work when it comes to hair IF you want to do it right. There is no escaping it :).

Blender is a powerful tool and it is getting better every other month. We hope they will keep improving it so that one day we could all escape from the claws of Autodesk. And if you do the rigs right in blender it will export correctly as well. Same goes to Maya and Max, one small hiearchy mistake and everything will mess up, this is the nature of game development where you have to put ten gloves on to work on anything.

Well as far as I am aware, there is a known bug in Blender that messes up the rig if you move the
bones around in object mode. But if you avoid setting off the bug by avoiding moving the bones
in object mode then the rig will be fine, except for the part sometimes when you export it
and it looks normal in unreal’s mesh editor, and the animations are playing at normal size, but soon as you add the mesg to your Third person BP player capsule, the mesh becomes all oversized and
you have to resize it down to the size of the capsule and then its fine and the animations are fine… I dunno why Unreal Engine sometimes does that. Is that to do with Blender?