What I've been working on! (November 2025 Edition)

Hiya everyone! As I said previously, I do want to post updates more frequently and reveal more behind the scenes things. Here's what I've been up to for the first half of November!

I've been working on writing a tool for making CAS 3D models! As you can see in the video above, the currently released version of Better Abs has some really strange shading around the neck and shoulders. I've found that for whatever reason, existing tools tend to import normals oddly.

With the new tool, I've been able to fix the shading! This will really help with close-ups of sims when using the mod.

Some more footage:

Getting this far has been relatively easy but time-consuming. There's not much documentation for The Sims 4's CAS geometry file format out there that's up-to-date. EA published a file format specification close to the launch of the game but didn't release what they changed in later packs.

The next thing I need to work on for the tool is to add slot assignment support. While the body visually changes, the animations when using clothes made with this tool currently do not adjust to the body shape of a sim. It's especially noticeable with actions such as hugging or kissing. This is pretty much the last thing I need to solve before releasing the update.

Other Stuff I'm Working On

Hey! Did you know I also make a tool for animations called s4animtools? I don't mention it much here but I've been working on it a lot recently too. I've been working on it in the "new_clip_splits_ui" branch.

Here's a brief rundown on what advantages you get when using s4animtools.

• Import multi-actor animations into the game super easily

  • In Sims4Studio's animation tools, you can only import one clip at a time. This is fine for poses, but for something like a two sim social interaction with a prop, it can get tedious selecting a sim, then importing, selecting the other sim... and so on until all actors in the scene have been imported.

• Keep multiple in-game clips in one blend file

  • If you're working on sim to object animations, it's super handy to have the ability to split an animation sequence into tiny parts. You can have an animation for the "getIn", the "getOut" and all the other animations for the sim and the object in one file!

• Design animations to support more body shapes

  • If you watch EA animations closely, you may notice that the hands adjust in order to not clip with the body of the sim. s4animtools supports assigning slot assignments and baking the animation data required to get it working in-game.

  s4animtools is not designed to replace Sims4Studio, but rather complement it. You'll need to use S4S in order to get object and sim models and rigs from the game. s4animtools is also still very much WIP, so tutorials for it aren't common yet.

Now that I've told you about s4animtools, I'll be showing off what I've been working for it in the next post!