Rigging is building a skeleton inside a 3D mesh, then binding the mesh to it (the process is called skinning or weight painting) so bones deform the geometry. In a game engine, that skeleton is what animation and mocap data make move.
1. I made a custom character in Blender, (but you can use your favorite 3d software) modelling it in a T-pose, with feet on the floor at the Origin and facing -Y. The character is about 180 cm tall – human sized. Then I exported as an .FBX including the textures.
2. in Mixamo I choose Upload Character, then click NEXT
3. Auto-rigger wants you to drag the coloured markers to the corresponding spots on your mesh. Make sure you dont mess up left and right. With Use Symmetry ticked it will mirror move the corresponding marker from the other side.
My mesh has no fingers so I choose Skeleton LOD No Fingers (25) from the drop down..then click NEXT
4 It will take a few mins but eventually you should see your mesh moving around. It will ask you to continue
5 Back in the main Mixamo window click DOWNLOAD to get the rigged version of character in a tpose
…In the DOWNLOAD SETTINGS window, keep the defaults – we want Skin With Skin -which will give us the Avatar with textures and No animation. We can import this to Unreal.
6 Now you can use the animations grid on the left to select animations and download them for your character.
…in the DOWNLOAD SETTINGS window this time set SKIN to Without Skin to just get the animation..
