Hello,
does anyone know how to make that in ue4?
Of course you can, but you’d have to properly rig the arms to create the animation first (maybe there are some animation packs on the parketplace already containing these animations, in that case you’d only need to retarget them to be able to use them with your custom character).
But how can i add the weapon with the bone hierarchy?
Because I need to add a constraint the weapon with the hands and then add ik.
You need to add a socket on the hand bone, you can do it from personal probably (right click on the bone). That socket is attached to the bone but you can modify relative transform as well. There is a useful option (dont remember but probably right click on the created socket) to attach a preview mesh, so you can check how it will looks. But this is only for preview, you will have to do the attachment manually for your character at start.
Better explained here: https://docs.unrealengine.com/en-us/Engine/Content/Types/SkeletalMeshes/Sockets
You can attach a weapon to the character skeleton using a socket. The weapon itself can be another skeletal mesh with its own bone hierarchy. You can see an example in the learn tab Shooter Demo.
But i wont have access to the bones of my weapon in my fps arms anim bp.
You should attach the weapon not in the animbp but the character bp