2018/02/28

Character face rig!

Hi!

Geril here. This month in my free time, just to expand our portfolio a little, I've created a new character. It's still heavily work-in-progress, but it's gotten interesting enough to show you! It's a standard character for use in Unreal 4 and made in Blender, as usual, but this time instead of creating our own skeleton from scratch, I made the skeleton based on this .blend file recommended by Epic for Unreal 4.


While I kept the bone structure and names of the original skeleton, I modified everything I needed to to suit the character, and - as always - I made a specific and unique facial rig. If you've been our reader for a while, you might have noticed that we prefer using shape keys/morph targets for our characters' faces. It's true that they are easier to use for games, but they also limit things quite a bit. And even though I love limitations, because limitations force me to be creative, it was about time for me to step out of my comfort zone and create a dedicated video game character complete with a bone-driven face rig. So I did. The face has a lot of bones that are constrained to a bunch of driver bones for easier use, so within a few seconds I can animate stupid faces for the poor character.


At least that's how it started.


Right now on the pictures and the attached video is a face with standard driver bones. The eyes will move by texture panning, but what will really be interesting is that we plan to swap out parts of the skeletal mesh during runtime. At first this might sound strange, especially for a rig like this, but we want to see how well the Unreal Engine handles this stuff.

The mesh swaps will happen on the fly: the face will be split into multiple smaller meshes (the splits will be invisible of course), and for example when the character blinks, the eye meshes will switch to a closed-eyed mesh version instead of the eyelids stretching over the eyes. We will need multiple meshes which are spread out in-between the open and closed eye states to make a smooth animation, and then we still have to solve how to handle the textures for these meshes. The upside is that we don't have to worry about texture stretching, because we'll be using separate meshes for O and U sounds, and even for sticking the tongue out.


But first we'll need a finished and stable face rig that could work standalone as well. The separate mesh pieces will be created using these weights too, and then modified in a way that leaves most of the weights intact. That way if the lips have a smile on them, and the mesh changes to an O-sound, the smile will stay. It sounds weird in text, but if all goes according to our plans, it should work pretty well. We'll have to change our animation style a bit to fit this technology, maybe make it snappier so the mesh changes won't look abrupt. The only question remaining is how UE4 will react to this all.

While I'm still working on the rig, Lussy's making the textures for the character. This takes up most of our free time now, so look forward to more posts about it in the coming months!

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