I stumbled upon this video, detailing a process to create 3D models for Unreal Engine by use of photogrammetry. Basically: take 1000 pictures of an object from all possible angles, import into a program called RealityCapture, press F6 and voila: you have a 3D model of your object. This technique could be extremely helpful in making locomotives! I hope DTG will use this process to create more detailed models of future trains.
You can't just import models like that to TSW or any other game engine since it most likely will have millions of tris. Looking at that mesh in Blender you will clearly see that the topology is just a big mess. It is nearly impossible to work with a mesh like that when you need to split up parts for animation etc. Making good texture maps will also become a problem. But photogrammetry for reference is great, especially for trains where you don't have good blueprints. So yes, it can be extremely helpful for devs. For scenery objects in Unreal Engine 5 it would probably work better, since UE5 is better at handling lots of tris (triangles/polygons) You could also try to use this method to bake details down to a low poly mesh.
Interesting. What I gathered from the video is that the tool also support texturing the model from the photos and exporting the textures separately to support Unreal's Blueprinting system. I guess it would also be possible to import the hi-res model in Blender and cut off the parts that require animation and handle those separately? But for locomotives, pretty much the entire body of the loco (so without bogies and pantograph) is static and does not require animation. Anyway, I just thought it looked cool.
If you import the model to Blender you will see what I mean. It is just a big mess with vertices and triangles everywhere. Reducing it to something that the sim can handle is a big task. When you capture the images you also capture the daylight, you don't want to have a static light on the object in the sim. So you need to remove that from textures, and create the necessary maps (rough, metallic, ao, normal map) so that the light in the sim is applied correctly. You want to keep the textures to a minimum. If you look at the textures in TSW and TSC you will find lots of generic textures that are used on multiple buildings. Having multiple 2/4k unique textures for each object will have a big impact on the performance (and download size of the DLC..) From a distance a photogrammetry model looks good. But up close you see all the distortions and noise. Just like with high-res LIDAR-data. Sometimes you just get too much data. But again, as reference it is great. https://sketchfab.com/3d-models/tra...ammetry-scan-328199a8beca4c3fbc989d342fd8f604
Some more examples here to look at https://sketchfab.com/miguelbandera...mmetry-scans-e7e54120aa8a4d9c82f27157aa4e71ab In the future maybe, in UE 5 with better photo scan than the examples above it might work.
Photogrammetry is nearly impossible with anything that has wide areas of same color or are shiny (modern trains). In theory pouring bucket of mud water and letting it dry would enable photogrammetry but would probably not be allowed by the owner of the rolling stock. Because of these reasons I am more interested in NVIDIA AI and NERFs: Also there is the variation of NERF called "gaussian splatting" but it doesn't allow direct mesh generation atleast at the moment:
While photogrammerty will produce a model with terrible topology and somewhat noisy surface, I think it can be pretty useful as a base for making the final model because it will give you exact dimensions for every little thing and figuring out 3d shapes from a set of photos normally takes quite a bit of time. Not to mention scaling everything properly so that it fits together. I wouldn't bake down photogrammetry-generated textures though as it contains all kinds of lighting effects and it's hard to modify if you want to, for example, enhance the surface definition in a specific spot.
On a related note, wonder if there might be mileage in looking for items in Google Sketch Up. Certainly a fair bit of the stuff in Trainz has been sourced that way.
You need so much time to cleanup and fix the result that you are better off using it as a reference as suggested by Thomas9970.
That is about all that I would use it for. Just a reference for creating city/town buildings,Flats/Apartments houses, Stations etc, in Blender.
