Unit Models in Rome Remastered

Total War: Rome Remastered - Modding
Main Article Creating a New Campaign Map File Differences from RTW Porting a Mod to Rome Remastered Unit Models in Rome Remastered Rome:Total War & Remastered - Modding Index Feral Interactive / Rome Remastered Github

Units in Rome Remastered use the same skeleton, animations and .cas type format as the original game. Remastered allows more detailed units, better 'movement' with vertexes able to be weighted across two bones, and more sophisticated graphical effects using PBR textures.

Feral's tech art guide to Characters provides detailed information on modding units.

Details of how to unpack existing models from the game packs can be found here.

Feral's Cas Converter tool will convert the unit model .cas files to .fbx, IWTE will convert RTW and Remastered models via .dae (Collada) and export in a cas format suitable for Remastered by default. Both tools are primarly designed to work with Blender but the .fbx and .dae formats can be used in other programs such as 3dsMax.

UV Mapping for Variations

Remastered allows variations of faces, hair and skin textures based on ethnicity. The sections of mesh that use these textures do not need to be in separate groups assigned to the textures, instead the texture used is determined by the relative position of the uv coordinates. The picture below shows a Berserker unit from Remastered with the uv mapping explained.

The textures for the face, skin and hair elements are in a long and thin format with multiple variations that the uv maps tile horizontally across to pick up the variants. The sections of texture selected for hair appear to be determined by the text file descr_unit_variation.txt. The skin and body sections presumably just scroll horizontally through their respective textures.

Bone Weighting

Unlike RTW Remastered allows full variable weighting for all 'body' components, so each vertex can be weighted proportionately across any two bones.

Primary and secondary weapons however have to each be fully weighted to just one bone. You also CAN NOT have multiple weapon components, e.g. a 'primary' shield on the back of an archer that switches to 'secondary' shield in hand.

Lods

All units must have files named:

whatever_name_lod0.cas

whatever_name_lod1.cas

whatever_name_lod2.cas

whatever_name_lod3.cas

as the DMB entry is solely to 'whatever_name' and the game then looks up the other lod names automatically. You can however use a lod1 (single weighted version) re-named appropriately if you don't yet have different versions of the model.