The TS4 skintone system has a lot of potential, and I've been working on a tool to make it easier to work with, similar to Skininator for TS3.
Definition of Terms: (These are the terms I'm using - they're not 'official'.)
TONE : A game file which defines a skintone. It links to the color images, the overlays, and contains various settings.
Skintone : The skin you click on in CAS, which is defined by a TONE file.
Body skin details : A texture with shading, contouring, and details such as muscles and belly buttons. (Yes, I know there's a separate 'skin details' in CAS. Couldn't think of a better term.) There are separate textures for each age/gender/bodytype.
Skin color image : A texture which applies color and some shading composited with the skin details. There is one skin color texture which is applied to all age/genders.
Overlay : A texture which is layered on top of the skin details and skin color. The ages and genders it applies to can be specified.
Tool Overview:
Create/Edit Custom Skin Colors
Cloning Tool : Clones game skintones and creates a package with the TONE files.
Clone Package Editor : Open and modify cloned packages.
TONE Manager : Add/Delete TONEs, modify flags defining the type and usage, modify the swatch color and various other settings, import and export the skin color images.
Overlay Manager : Add/Delete overlays, define which ages/genders each overlay applies to, import and export overlay images.
Previewer : Preview skintones.
Create/Edit Default Replacement Skin Details
Make New Default Replacement Package : Select which skin details you want to replace and clone them to a new package.
Edit/Test Default Replacement Package : Import/Export textures and preview the skin details.
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