Also,I only play singleplayer.I dont care about creating a server. Am I still gonna be able to add 3D models into my world?
Yes, basically everything that's available in multiplayer is available in singleplayer as well. The same applies to the API ![]()
Lastly,this locomotive model below is 2Mb and now I know it wont carry textures
This still looks like a high detail model.. Can you eventually provide a link to the model file? Then I can tell you more about it^^
It really depends on what you want to do exactly. For example if the loc has 100,000 triangles, that's quite a lot (I'd say it's "too much"), however, if you just want to use it in singleplayer and place 5 locs in your world and that's it, you won't have any problems at all.
One have to watch out to not exceed a certain triangle limit. Modern graphics cards can handle between 1 and 10 million triangles quite well.
How do I split the model into sections to add the texture in each one?
You have to do that in a 3D modelling program. For example 3D Studio Max, Cinema4D or Blender (which is available for free).