VRcade Shooter: Fixing My First Animation Problem

This post should be short and sweet. It’s about an issue that took up just enough time to talk about it.

As I mentioned before, I’m happily charging into new territory by creating animations for a character in Blender, importing that animated character into Unity, then utilizing that animated character in my game. Needless to say, getting a feel for that process is going to greatly improve my projects, so I’m embracing the growing pains as I get the first animation or two in place.

That first pain appeared suddenly after I showed off the generic enemy armature I put together in recent posts. In fact, the issue was present in this screenshot. Notice anything about that pelvis bone?

Here’s how this character got his weird tailbone: As we’ve established, this figure is going to remain dead simple, so his skeleton will be a simplified version of anything you’d normally see assigned to a typical character: no finger bones, a three-bone spine, etc. When I completed my first pass at the armature, the pelvis piece didn’t have a dedicated bone at all. The spine started at the top of the pelvis and extended up thorough the top of the chest piece where the neck began. This would move the chest piece as needed and also serve as the parent bone for the other major bone connections. This setup got me through the basic pose test, but moving the model using that parent bone revealed that the unassigned pelvis piece would be left behind completely without its own connected bone. Figuring I hadn’t seen the end of this problem, I extruded a new bone straight down from the parent bone, connected it with the pelvis vertex group, and moved on, knowing all my pieces were at least attached.

As soon as I tried a full-body post, knew I’d made a mistake. Rotating the pelvis bone or the parent bone suddenly had unintended effects on the skeleton and the model.

I started to panic. Mistakes in Blender are scary, because at many points in history, they’ve been difficult or impossible to fix. If I had to ditch this armature and start over before renaming each bone again to match its vertex group, I knew I was going to take the kind of frustration break that often puts a project in jeopardy.

Much to my surprise, turning the armature I had into the armature I needed was as smooth a process as I could have hoped for. Undoing parent relationships works better in Blender now than at any other time I’ve tried it. Disconnecting the pelvis bone, rotating it in place, then setting the new parent relationships required to use it as the new primary bone for the armature gave me exactly the results I wanted without nearly the time or effort I was concerned about.

With the right armature for the model in place, I began working with the basic Dope Sheet and quickly determined that the best animation work was going to require the graph editor (for easing between keyframes) and the most efficient animation would require Blender’s Inverse Kinematic system, both of which I’ll cover in posts this week.

Stay tuned!

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