Placing a gun in the proper spot in UE4 for VR?

I’m trying to learn the “proper” pipeline for this instead of just smashing a static mesh on my actor until it looks right…So far, what I’ve found is that I need the following:

  1. A rigged gun. Mine only needs to be grabbed at the grip, so it has a bone for the main gun body, and a bone for the grip as a child underneath it.

  2. An animation state for the hand to look realistic wrapped around it. I pulled the default VR mannequin hand out of Unreal and positioned it around my grip in Maya. I then exported that as an FBX, and imported it as an animation. I think I want to use something called a Blend Space, but please correct me if there’s a better way.

  3. A socket for the gun to go into on the hand. I created a socket by opening the skeleton, right clicking the main hand bone, and adding a socket.

  4. I then made a blueprint for attaching the gun. It can be seen in this screenshot at the bottom of the post. It’s pretty similar to the default grabbable cube BP.

  5. I tested the blueprint. After a while and some difficulties, I’m now able to grab the gun. It’s pointing the wrong direction. So I go back into 3DS Max and reorient the gun to point along the positive X axis.

  6. The gun now points the correct direction, but it doesn’t fit quite right with the hand. The mannequin hand is grabbing it not around the grip, but a little bit above and behind it, in between the grip and the stock. The gun is also pointing up into the air (this is partially just because of how the gun is. The grip is completely vertical. This is not the final gun).

That’s where I’m at right now. I’ve read a little bit about IKs, but I’m not sure if that’s what I need for this. There are lots of suggestions online about having the gun spawn in, attached to the actor, but that of course does not work for Virtual Reality. We want the person to be able to pick up the gun, toss it from hand to hand and whatnot.

Are there any criticisms on what I’ve done so far? And how can I get the gun to attach in the proper location? Thanks.

Imgur

I use a joint in the hand which get exported with the hand pose animation. Add a socket to that joint and you can orient the socket so that it matches what you see in your app.