Blender, what imports to Unity as an "Empty" gameobject?

Unity Engine
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1

Hi all

I want to mark several points on a model with “Empty” game objects, I figured this would be much easier/quicker in the long run to use blender. So I was wondering what objects in blender export to Unity as “Empty” objects. I could only find information to do this from Maya.

Any thoughts would be great.

Thanks

Kel

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An empty transforms? For Blender my guess would be Shift+A >Empty

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Yeah i tried those but they did not seem to come over at all even when I expanded the asset in Unity. :frowning:

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I use bones for transforms.

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Cheers ill give them a go.

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Connected bones will be in hierachy, first as the parent and so on. Independent bones will be separated. Every bone will be an empty transform with the name of the bone. You just have to put no vertex weights on them.

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7

That worked exactly like I wanted. Thanks for helping. Quick question though, are bones “expensive” to use, and if I attach a trigger to the bone is it best to also give it a Rigidbody (I read if you are moving a trigger it should have a rigidbody) even if my main object has a rigidbody modifier?

Thanks again.

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As long as the bones aren’t connected to vertices, there shouldn’t be any further performance impact, but I don’t know it for sure. But if you look at uma, they use about 100 bones for blendshapes replacement. Each bone has vertice weights to deform certain face or body parts. You might look at unitys profiler. You could put like 500 empty bones without weights on it and compare fps at runtime. Compare both scenarios, with and without 500 bones in the model. If you don’t get any fps drop or at least almost, you shouldn’t worry about it.

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I used Empty->Plain Axes in Blender for attachment points for my character in Horde Rush. “Plain Axes” has the added advantage that you can easily visualize the orientation so that props like the sword and bow snap properly into the hand. I export FBX from Blender. For this to work, the “Empty” category has to be selected in the export options.

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10

Sounds even better than bones, if you don’t need them to be parented in a hierachy. Gonna try out that alternative in maya.

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Thanks mate, ill give it a go.

Thanks aer0ace, I will give that a go as well.

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Er, I should probably mention some other things to get it fully working. Make sure to position the Empty in Rest Position, not Pose Position.

Also, if you are using the Rigify to Unity asset, you need to add a substring of the Empty’s name in the SpecialBones->Exception Bones field. Otherwise, Rigify to Unity will strip it away from the bone hierarchy.

For example, I named my Emptys “attach.L” and “attach.R”. The Exception Bones field has “attach” in it, so that it gets imported into Unity along with the rest of the Rigify armature.

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13

This thread kind of sounds like it may help me with a problem I’m having.
I’ve been trying to attach objects to hands in animated models I have, but when I import from blender I only see the IK handles in the hierarchy and they have static (position doesn’t change during animation) transform info.
I guess I somehow have to have a bone outside of the IK that’s near the hand and keeps with the animation?

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Sounds like a lot of problems that may or may not have anything to do with each other.

I believe you have to attach the objects in Pose mode, ideally on the first frame of the animation, if it is to remain attached to the hands. I am assuming you are parenting to the bone hands and not the model. Also, are you using Rigify? I can’t comment on the IK stuff otherwise. Other than you shouldn’t be parenting anything on the IK objects, as they are supposed to get stripped when importing to Unity.