Making of a BR Class 37 cab - Part 2

By Tony_Hilliam, June 14 2019

In this blog series we will be looking into the development of a brand new Class 37 interior. This project is being undertaken by Brendan Dennish (Trainz Community member GDennish) who has been contracted by N3V Games during his summer break.

UV Mapping

After the modelling process is complete, the next step is UV mapping. When unwrapping a model, you can imagine how it will fold out from its 3D mesh shape to a flat 2D image. (Interestingly, the U and V denote the axes of the 2D texture and are used since x, y and z are already taken by the axes of the 3D model).

The 3D model is on the left, the "unwrapped" 2D version is on the right.

This needs to be done for every part of the model, which is almost as time consuming as modelling it!

After unwrapping an object, it needs to be placed onto the UV map, which contains all of the objects unwrapped on a flat texture. Assembling the UV map is like playing a game of Tetris – fitting it all together can be a challenge! 

Here we are unwrapping all the controls.

After unwrapping comes texturing, which in my opinion is the most enjoyable part. My preferred texturing method is to use Substance Painter, which could be compared to a 3D version of Photoshop. 

Here's the first pass at the texturing on the front of the cab.

And another shot showing some of the controls now textured.

Adding more detail to the controls.

Everything is done in real time using the PBR (Physically-Based Rendering" workflow so the results will be almost the same in the tools as in Trainz.

I use the same reference photos I gathered for modelling to get an idea which colors go where, and where the fine details should go.

With Substance Painter, algorithms can be used to generate dirt collection on the fly but sometimes you still need the artist's touch.

Here's the front of the cab ready to go to N3V Games for feedback on things like weathering, dirt/grime, texture resolution etc.

And let's not forget the back of the cab!

And don't forget to check things out in-game as well (even though there's still plenty of work remaining)!

I hope you enjoyed this weeks look at the cab. It's so rewarding seeing everything come together. 

Next week I'll be working on the feedback so far and polishing the textures and model components.