This post comes from the Penumbra Discord. Written by Spiswel. I think this is a great explanation that I use to explain to my friends about the body packs around FFXIV Modding. 


About Bibo and Gen3 bodies. 

A body mod will install an improved vanilla skin and new extremely high-quality skins for modded gear. 
Tight&Firm3 is called Gen3 as it is the 3rd generation of body mod that allowed for asymmetrical designs. Mods were allowed to be paywalled for a set time. 
Bibo+ came after T&F3 and contained some differences the way assets were laid out. Bibo+ allowed mods to be paywalled which caused a huge boon of modders to start converted existing mods and sets from other games to be now installed in FFXIV. 


About FFXIV Bodies

– They are not a blank naked base that clothing is added to.
– They are actually like Lego People broken down into several components namely Body, Legs, Feet, Hands. 

These ‘components’ are what you swap in/out when equipping different things, INCLUDING the “naked” versions (known commonly as Small Clothes, Emperor’s Set and NPC Small Clothes).


This means various things:

– Vanilla components will not conform to a base body mod’s shape until their 3D model has been replaced with the base body mod
– Vanilla components will always use the vanilla skin material (known commonly as material A)
– Base body mods will always provide a vanilla material A version of their skin so as not to break vanilla components

A 3D model for a gear piece (even the “naked body” parts) is basically a 3D shell mapped out (read: unrolled unto) a 2D skin material. This is known as the model’s UV Mapping. Each broad category of body mod (between vanilla, Bibo+, Gen3, TBSE, HRbody3, Otopop etc)’s 3D models come with their own specific ‘arrangement’ of where the skin islands for parts X and Y are.

Generally, at least a few layouts will be provided by a given body mod from the start: the vanilla material A + its own asymmetrical material + compatibility materials for other bodies.
Ex: the Bibo+ body for tall females provides materials A, BIBO (Bibo layout) and B (gen3 layout), and the TBSE body for tall males provides materials A and B (tbse layout) from the start.


What does that mean for skin mods?

To make a skin mod like a tattoo, scales, freckles, or muscles look good on any type of character, it needs to be applied to all the materials that are relevant to that character’s race and gender. For tall female characters, this means applying the mod to at least three different layouts: vanilla, bibo, and gen3. Some body addons may include the necessary textures in existing layouts, like Bibo+ Trans Redux and Gen3 F*ta, to make it easier to achieve seamless coverage with fewer materials.

Conversely, if a skin mod does NOT provide all the layouts required, equipping a component using a different layout (ie TBSE body -> vanilla body) will display the untouched skin material instead, and your skin mod will “disappear” from view. Equipping an item with the correct body layout will make it re-appear.

There are a few particulars surrounding the vanilla material A:
– since it’s hard-coded to be symmetrical, any skin mods applied to it will mirror from left to right
– asymmetrical skin mods CANNOT be displayed as intended on a vanilla component


My skin mod is missing a layout, what do?

There is no miracle solution for this, but solutions DO exist:
– locating the original creator of the skin mod in question and asking them (nicely!) about an update / addition / conversion to a new layout
– locating the original mod’s creator files (transparent overlays, PSD files, renders etc) or ripping them from the mod itself and converting them YOURSELF to the needed layout


Using Texture Compiler

A very elegant tool used to quickly convert textures between Bibo, Gen3 and Vanilla