Thanks, John. I'll read those. So far I've read and tried to follow two diff sets of instructions. They are woefully incomplete. I have Photoshop, and know my way around it. I took the original 'body' tga and modified it, but it was not at all clear where the two body halves were divided in the original pic, and I got wonky results. Even though I "cloned" the asset, all I ever see is the original one. Even though I cloned it again and changed the Username as one instruction showed - that asset with the new name doesn't show up anywhere. I'll try your set of instructions next. I have done complicated things in the past, turning 3D models into planes and helicopters in RC flight sims. I just need an actual set of good instructions that actually includes all the necessary steps the first time around.
If you cloned an asset, it'll appear in Open for Edit as "New Asset" in Content Manager. If you searched for your asset to clone, you need to clear out the searched-for name, otherwise, your "New Asset" won't appear either. You need to edit the config.txt file and update the Username and description. Keep the quotes and formatting as is. Once you change the username and submit the asset, after making your texture changes, your model will appear in Content Manager and in Surveyor ready for placing.
Reskinning is not that difficult to do, it just takes time to do it and requires patience. What helps is thinking of the textures as decals on a plastic model with the difference being these textures aren't cut off and glued to the model and remain on the sheet. When reskinning models, you'll use the basic tools in your photo editor such as recolor, painting, cloning, and a layer or two to float new logos and things into place.
Texturing comes in three forms in Trainz models. The oldest models, not counting Paint shed models which are a different animal altogether, use the simple texture for each part method. While this is a simple way of texturing, it's a memory hog and it's actually more complex in some ways to texture because you have to repeat steps such as recoloring and painting more than once.
The more modern models use a different method called UVW-mapping. UVW mapping is an X, Y system plus W for type of texture with the type being spherical, cubic, or planar. Locomotive textures are planar for obvious reasons because the surface has to hold windows, logos, and other details. The UVW maps are generated by the 3d modeling program such as Blender. Instead of placing the textures into individual files, these textures are placed into a single file and positioned to fit. What helps is thinking of this UVW-mapped file as a decal sheet. You'll see windows, logos, doorways, you name it, all squeezed carefully on to the "sheet" as if these are decals ready to be cut out and placed on to the plastic, I mean 3d, model.
Editing these files is much the same using the same tools. The advantage is you can do things once in most cases and not have to repeat some steps over and over such as recoloring, painting over logos, and other steps. The problem, however, is some of these newer models have what are called normal maps. A normal map is a black and white representation of the texture that affects the height. Some photo-editing programs such as Photoshop can generate a normal map. This does make things a bit more difficult, and I recommend reading up on this to get a handle on it. My hunch is after replacing textures and adding in new logos, you will need to recreate a new Normal map, which is saved to a file.
