Downloads:

CASDesignerToolkit-win32-i386.zip 1.4 MB
Windows binaries
3 days, 7 hours ago
CASDesignerToolkit-linux-amd64.zip 20.0 MB
Linux binaries
3 days, 7 hours ago

CAS Designer Toolkit

Event: Christmas & New Year

Project: CAS Designer Toolkit


Uploaded Dec. 25, 2025, midnight

Updated Dec. 25, 2025, 2:59 a.m.

Socials: Reddit ModTheSims

3 132 14

Merry Christmas, everyone!

Due to numerous issues related to existing tools for editing CAS parts, I decided to make my own.

Currently, it supports the following features:

  • Editing part flags (e.g., age, gender, species, categories, etc.)
  • Adding, editing, and deleting presets
  • Importing/exporting GEOMs, OBJs, and WSOs
  • Displaying morphs
  • Changing the shaders and material properties of mesh groups
  • Adding mesh groups to LODs

Support for the following is planned:

  • Assigning morphs and bones (both of which in the meantime can be done in Meshing Toolkit)
  • Creating patterns (this can be done in the meantime with Delphy's Pattern Packager)
  • Displaying a full Sim in the 3D renderer

It's lightweight and runs on both Windows and Linux (macOS support planned). For Windows, .NET Framework 4.0 and GTK# 2.12 are required (check the download's instructions).

Do note that this tool has not been 100% tested due to scarcity of testers (the tool is very niche); please be patient and explain whatever issue there is to me.

Source code available here

Acknowledgements

Below is a list of people who helped with this project either directly or indirectly (as well as their contributions):

  • Peter L. Jones – Provided the S3PI library which serves as the basis of this tool and many other Sims 3 tools
  • CmarNYC – Her code for TS3SimRipper helped with applying patterns to textures and displaying morphs in the 3D renderer; the code for her Meshing Toolkit for importing/exporting OBJs and WSOs was also borrowed
  • MonoChaos – Provided the icon for the tool and helped test the tool for issues
  • zoeoe – Helped with issues related to the S3PI library
  • VirtualHugs – Helped with explaining things related to CASPs; I'm not a mesher, so her advice was incredibly helpful

Testers:

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