We now have several different meshing options, which is great for everyone, but also a moving target to document. I can’t have possibly tried every kind of mesh in every program, and I can use your help in making this document more complete. Please PM me suggestions to add to this document – I just want to get this all in one place.

For an overview of a mesh and its parts, see Everything You Wanted to Know About Meshes But Were Afraid to Ask

Modifying body meshes have some parts in common with creating objects; they have a mesh, uv map, and a texture. But they also (like some select objects) have 'bone' assignments that enable them to animate in the game. This article will outline which tools can be used to modify body meshes, links to appropriate tutorials, tips for specific issues folks run into, and for those who want to know more, some of the technical details involved in working with body and hair meshes.

There are primarily 4 ways most people modify body meshes. As Maxis did not supply us with any tools to make or modify body meshes, each of these tools have specific strengths and limitations. It is important when you begin to modify a mesh that you choose the tool best suited for your end goal.

A 'mesh' which gives the sim its shape is a collection of triangular polygons connected together to create a 3D shape. The mesh file also contains the bone assignments for the points, a uv map describing how graphics are applied to the mesh, 'normals' that tell the software how to smooth your mesh's shape, and morph data for making the sim fit, fat, or pregnant.

To edit your mesh you will need Simpe, Meshtool or Wes' Milkshape Plugins, and an appropriate 3-D editor, such as Milkshape. 3DS Max or Modtool. Generally must start with a Maxis body/hair/accessory mesh that you then modify to create your new mesh, because you need the skeleton.

You must understand that each of these editing options are DIFFERENT, and have different options/features/drawbacks. Sometimes the editing you can do is limited, sometimes the choice of programs to use is limited. Some are more complex to use than others. So please read on

Quick List: Combinations of tools that can be used to edit body, hair, and accessory meshes (not all are listed)

Meshtool (obj) (Milkshape, Maya, Wings, Blender)
Wes’ Unimesh Milkshape Plugin
SimPE SMD Import/Export (XSI Modtool, 3DS Max, Blender, others)
SimPE Import/Export (Milkshape)
Poser Magnets (in conjunction with one of the other tools)

Click on the name in the index to see details about each one, or scroll further down this message. You can get more details about the programs needed, tips, tricks, tutorials, and so on for each.

And for completeness, outdated
Outdated Wes’ Bodychop Plugin
Outdated Wes’ plugin
Meshtool (smd) (no morphs, use the new SimPE export)

(Special thanks to Dr Pixel, Wes, Skankyboy, Quaxi, Kate at Parsimoneous, Miche, and Delphy for sharing their knowledge so freely.)