I guess this is more of a blender question. How do you join two tubes together. E.g. when "welding" a roll cage, two individual tubes are joined. How do I simulate this in blender that will allow for exporting into BeamNG?
i normally change the selection mode to not be vertices but edges and select one edge on one tube, the corresponding edge on the other tube (assuming they are the same) and hit F there may be a better way to do it, but i am unaware of it then just do that for all edges
Not all tubes are welded together even in vanilla cars I believe, but to join tubes together you select two and press ctrl+j. You can export them as separate meshes too if you want, then just add more flexbody lines to .jbeam file. Welding vertices is then how all meshes are built in Blender, but there are also some handy tricks for that on YT, like this for example: Then another welding is to make tubes look like having a weld seam, this is skipped on rollcages often, but if seam is visible on driving view, some simple flattened tube with normal map might add quite bit to visual quality, imo. Just don't make weld seams by sculpting like you can find on YT as that is for highpoly modeling, not for game modeling. For rollcage to actually function as rollcage, you will then need beams and nodes for said rollcage, set node group and in your flexbody definition of rollcage make sure you use that rollcage node group to connect your 3d model to node/beam skeleton. Check sections Flexbody and nodes in this https://wiki.beamng.com/JBeam_Introduction
I don't have much to say, but just wanted to tell that this is true for the vanilla cars. Almost (if not) all parts are "loose", be it tubes, hoses, suspension parts etc. The only way I know how to make a "weld" is when you attach the end of a tube to a flat plane. After doing so, you bevel the contact point between those 2 meshes & it should somewhat look like a weld (as can be seen below): (used the B1 as an example)
Starting from the weld seam, I could do something like this, but essentially I would think that just having a edge loop scaling it and then beveling it would do fine for most cases, then with weld normal map it could look something like okay, maybe. Then again UV mapping stage would be a lot of extra work and not sure what could happen with deforming, is that part of the reason why vanilla rollcage are done how they are? I did try to record a video, but I kept forgetting what keys to press etc. I'm so great with this stuff
To be honest, I have no idea why is it like that... maybe it's for deforming, maybe it's better that way? Who knows But as for UV mapping, I don't think it would be that hard to have a weld texture on the connecting part of the tubes, as that would be just a simple "wave" pattern on where the tubes connect